Gildas Brégain

Policies for Disabled People in the French Colonies (1918-1962) : Evolutions and Heterogeneity

Studies on disability in colonized territories are scarce and generally limited to the analysis of a specific category of disability in one particular colonized territory, such as blindness in Kenya or Algeria. 1 These studies do not address the complexity and heterogeneity of the way in which disabled people were treated across the imperial world. Through examining the policies implemented to assist different categories of civilian disabled people (blind, physically impaired, and injured workers) across the French Empire, this chapter demonstrates the extreme diversity in the way in which different disabled populations were treated even within a single empire. The findings of this study paint a complex picture. Disabled people were treated differently in different administrative categories of the French Empire (former colonies, new colonies, protectorates and mandates). Different resident populations (French/foreign/indigenous) were also treated differently based on legally legitimized racist conceptions (code de l'indigénat). Further, those who were differently impaired were treated differently even within the same colony and the same group of the resident population.

This chapter focusses on three colonies with different statuses within the French Empire. The first is a settlement colony, Algeria, which was legally incorporated into the French territory and divided into three French departments by the Ministry of the Interior. The second is a more traditional colony, the French West African Federation (FWA), which encompassed considerable diversity within itself. In the 1920s, the FWA brought together eight French colonies in a single federation: Mauritania, Senegal, French Sudan, French Guinea, Ivory Coast, Niger, Upper Volta, and Dahomey. The FWA was headed by a Governor General who lived in Dakar. The third colony is Madagascar, another traditional colony that depended on the Ministry of the Colonies and then on the Ministry of Overseas France from 1946 to 1959. In 1946, Algeria, the FWA, and Madagascar became part of the French Union, and in 1958, they became part of the French Community. The FWA and Madagascar gained their independence in 1960, while Algeria won its independence in 1962. Comparing the policies aimed at assisting civilian disabled people developed in these colonies allows us to more broadly understand the complexity of imperial social policies across the French Empire. Because this is a chapter about imperial practices, only the policies developed by Europeans through the provision of economic and social services are discussed, without considering the care and assistance practices of indigenous populations, which, of course, concerned large parts of the population and were highly diverse in their own right.

The aim of the chapter is to identify the characteristics and development of imperial policies used to assist different categories of civilian disabled people (blind people, injured workers, and the physically impaired) and to highlight the heterogeneities of these policies in colonized territories. This work suggests the particularity of the geographical location as a highly important factor that determines how disabled lives were led. The study is based on colonial archives in France, archives in Algeria, other administrative archives in France, as well as the colonial press. It should of course be remembered that these colonial archives are not neutral, rather they were produced 'by and for the institutions that dominate the [indigenous] population'. 2 It is therefore unsurprising that in the course of the chapter, the sources consulted provide more information on the rights and benefits allegedly conferred to disabled people, rather than on their concrete experiences and life trajectories. This chapter begins by specifying the characteristics of imperial policies to assist disabled people across various locations and then analyses the role and motivation of various actors in the development of these social policies.

Low-Funded and Low-Priority Social Policies for Injured Workers, Blind People, and Civilians Who Were Physically Impaired

This section aims to clarify the characteristics of imperial policies to assist disabled people, including analysing the territorial and ethnic inequalities in these policies. The importance of each disabled population in each territory and the administrative status of each colony led to differences in the treatment of disabled people across the French Empire. This chapter argues that the French authorities, both at a pan-imperial scale and in each colony, adopted different logics of action according to the nature of each disabled population (war veterans, injured workers, blind people, physically impaired civilians, leprosy sufferers, etc.). For example, the social policy for disabled war veterans was prioritized over that of civilians not only due to the political imperative of recognizing those who had sacrificed themselves for France but also, above all, to maintain the sympathy of the colonized populations in North Africa and the political support of wounded former soldiers in the context of growing anti-colonial nationalism. 3 Meanwhile, leprosy sufferers were treated following a different logic. A policy of authoritarian segregation of indigenous leprosy sufferers was developed, aimed at avoiding any contagion, especially of Europeans, in order to preserve this labour force and military resource for armed conflict. 4 This chapter focusses on assistance to injured workers, blind people, and physically impaired civilians.

A. The Weak Protection of Injured Workers: Maintaining Permissive Labour Rights until the 1930s

While we do not know the precise number of work-related injuries sustained in the colonies studied, it is certain that the numbers we are dealing with are high. In Algeria, the judicial authority listed 73,539 accidents at work in 1953 alone, 3160 of which resulted in partial permanent disability. [START_REF][END_REF] For a long time, these thousands of injured workers were not legally protected in colonies. Only Europeans recruited in France 'were protected by case law'. [START_REF] Le | Histoire du droit du travail dans les colonies françaises[END_REF] If other injured workers wished to be compensated, they had to prove their employers had been at fault, which was very difficult. Judges of the Court of Cassation (the highest court in the French judiciary) sometimes mobilized the Civil Code to defend the Europeans who were victims of serious accidents in colonies, but this was not possible for indigenous workers.

This situation changed in the colonies studied between the two world wars when no-fault employer liability was introduced. Tellingly, this movement was several decades after the adoption, in metropolitan France, of the law of 9 April 1898, which conferred to victims of industrial accidents the right to compensation proportional to their degree of incapacity, applying the principle of no-fault employer liability. It was implemented in colonial territories in a sporadic manner. It was made applicable in Algeria by a law adopted on 25 September 1919, but was applied much later in the other two colonies: 1932 in the FWA and in 1937 in Madagascar. The actual application of these texts was even later. The beneficiaries of this legislation were generally restricted either to industrial and agricultural workers operating engines and machinery (in the FWA) or to workers of the Service de la main d'oeuvre obligatoire pour les travaux d'intérêt général [Mandatory Labour Service] in Madagascar. [START_REF] Gheerbrandt | La législation sur les accidents du travail aux Colonies. Un premier stade d'application aux Antilles et à la Réunion[END_REF] During the 1940s, several laws were passed in metropolitan France to provide better protection for injured workers, such as conferring compensation for employee victims of industrial accidents by the social security system (in particular, the law of 30 October 1946). Again, there was a sharp division in these developments between metropolitan France and in colonies. This legislation was not de jure applicable in colonies.

In the 1950s, however, legislation on occupational accidents started to evolve in Algeria. The Algerian Assembly adopted a decision (No. 52-022) approved by the decree of 19 July 1952 and by the law of 25 July 1952, which extended the scope of application of the legislation to accidents on the way to work and extended the beneficiaries of such legislation to people working at home, travellers, detainees, probation officers, and other workers. 8 Two years later, the benefits for workers' compensation were also revalorized. So, the number of people receiving workers' compensation benefits increased considerably in the 1950s. The Regional Mutual Agricultural Social Insurance Funds paid disability benefits in the 1950s to several hundreds of social insurers (36 in 1951, 104 in 1952, 117 in 1953) in Algeria, but denied this right to compensation to several hundred others. 9 The situation was rather different in the FWA and Madagascar. Here, case law (FWA Court of Appeal of 14 January 1949; Dakar Court of First Instance of 22 July 1950) considered that while employees of metropolitan origin benefited from metropolitan legislation on accidents at work, including the law of 30 October 1946, indigenous people did not. [START_REF]1 AFF POL 3670[END_REF] This discriminatory legal situation for indigenous people led the Ministry of Overseas France to envisage, as early as 1951, an overhaul of legislation on the reparation of accidents at work in order to confer these benefits of metropolitan legislation to all citizens of the French Union. Six years later, however, no legislation had been adopted on this subject, despite the demands of several actors (trade unions, the High Labour Council, the Fédération Nationale des Mutilés du Travail [the National Federation for those with Workplace Injuries], and political leaders), who had advocated for the application of similar measures in the territories of the French Union. It was not until 1957 and 1958 when the metropolitan authorities finally published several decrees (No. 57-245 of 24 February 1957 and No. 57.829 of 23 July 1957) and orders (24 September 1958) that determined the procedures for compensation and prevention of occupational accidents in overseas territories. These legislative provisions extended the principle of occupational risk to all overseas territories. The employer was thereon held responsible for primary emergency care and obliged to affiliate all their workers to the Caisses de compensation des prestations familiales. However, each overseas territory remained sovereign in determining the measures to compensate for occupational accidents. The Head of the territory was responsible for setting a whole series of fundamental details (amounts of daily allowances, contribution rates, etc.), after deliberation by the Territorial Assembly on the subject. However, these metropolitan provisions essentially remained dead letters, as the adoption of the new French Constitution of 4 October 1958 affirmed the autonomy of FWA and Madagascar in their decisions in matters of labour and social security (and therefore also in the field of compensation for accidents at work).

In the end, only a few people got compensation through the law. Nevertheless, mutual aid or charity associations provided immediate relief to some injured people. In Bône (Algeria), the Caisse du Secours Immédiat (Immediate Relief Fund), run by a lay-sister of charity, Mathilde Maire-Caussin, provided occasional relief to victims of occupational accidents and their families. This was also the case in Madagascar. In other cases, those injured at work found themselves without resources, forced to pursue a different profession or to beg. In some cases, it was family or community solidarity (Jewish or Muslim) that helped them economically.

In these three colonies studied, gradual evolution of compensation policies for injured workers can be observed from the 1930s onwards, towards a logic of the right to compensation based on the principle of occupational risk and towards a widening of the beneficiaries. But these policies were not only limited in their effect with a low number of beneficiaries, but very fragmented in realization in terms of both their racialization (they were long reserved for Europeans) and their location (different legislation was introduced to different colonies at different moments). Finally, no vocational re-education schools were organized for injured workers, although some Algerian injured workers were referred to vocational training centres in Algeria.

The considerable delay in the adoption of legislation on compensation for accidents at work and the relatively weak protection of workers' rights in colonies were mainly due to the colonial authorities' desire not to hinder the exploitation of indigenous labour by French settlers while protecting a labour force (both European and indigenous) that used dangerous machines. [START_REF] Fabre | Le sort du travailleur expatrié aux colonies. Des juges entre intransigeance et mansuétude[END_REF] It was also due to the refusal of the French authorities to contribute to compensation measures. Furthermore, there were many technical problems involved in setting up a system comparable to that of metropolitan France. [START_REF] Fr Anom | Note on the management of work-related accident risk in the Overseas Departments and the extension of the system in the Overseas Territories[END_REF]

B. Leaving Blind People and Those with Physical Impairments to the Care of Charity and Preventing Them from Begging

In the early 1950s, more than 110, 900 blind people were registered in the FWA, about 4,000 in Madagascar, and about 20,000 in Algeria. [START_REF] Fr Nap | [END_REF] The high number of blind people in the FWA is partly linked to the ravages of onchocerciasis and other types of ophthalmic problems in these territories. Statistics on the number of physically impaired civilians in these settlements are not available, but the numbers can be similarly high. In the colonies studied, blind or disabled adults (indigenous or Europeans) who were indigent and unable to work were sometimes placed in hospitals or asylums. In Algeria, they could also receive monthly 'home help' from some municipalities; however, this aid was granted on an optional basis. Disabled people who were more than 65 years old also received a higher monthly allowance. Poor disabled people without family support also received occasional assistance in the form of the distribution of cereals, clothing, cloth, wool, or money. Some assistance was also provided by the Muslim and Jewish religious communities, either monetarily or in terms of goods (food, clothing, etc.).

In early-twentieth-century Algeria and Madagascar, there was a residual supply of educational or professional services provided by private actors (associations in Algeria, a religious mission in Madagascar). In both places, several dozen blind children had access to a specialized school for teaching Braille. Schools were opened in Algiers in 1920, Oran (Algeria) in 1941, Alakamisy-Ambohimaha (Madagascar) in 1909, and Loharano (Madagascar) in 1924. The school in Algiers was managed by a subsidiary association of the Valentin Haüy Association, the one in Oran was run by the Federation of the Blind of Algeria, and the one in Madagascar was run by a Norwegian Protestant missionary. These schools received public subsidies from municipalities and colonial governments. During the 1950s, Algerian schools welcomed about 60 students every year, while the school in Madagascar received 15 students annually (a total of 87 students from 1924 to 1951). There were no schools in the FWA. In Algeria, at least 100 indigenous blind adults had the opportunity to follow a professional apprenticeship and work in blind workshops in Algiers, Oran, and Bône, as brush makers or basket makers. The Municipal Institute for the Hard-working Blind in Algiers hosted about 30 workers, mainly blind Muslims. In Madagascar, blind adolescents at the Loharano Institute received vocational training (in caning, weaving, matting, knitting, tapestry, embroidery, etc.). Unlike blind people, the physically impaired only had access to vocational training very late, from the mid-1950s, that too in only one territory (Algeria). They had access to training as watchmakers in Algiers or as television and radio repairers in El Biar, offered mostly by the Association des paralysés d'Algérie. [START_REF] Fr Anom | Director of Social Action to the Minister of State for Algerian Affairs. 15 L'Echo d'Alger[END_REF] Until the 1950s, the governments of the colonies studied considered that responsibility for the creation and management of educational and professional works for disabled civilians did not lay with them, but with private charities. Rather than creating institutions, which was expensive, the authorities preferred to provide individual scholarships for some poor blind or disabled children to attend private schools in Algeria or metropolitan France and to provide occasional subsidies to associations. The colonial elites were also motivated by the desire to eradicate begging by blind people in the major cities of the colonies and to 'moralize' the aid granted by promoting the exercise of a profession. 15 Massive changes occurred in the 1950s as colonial governments started to assume responsibility for the social protection of blind people and the physically impaired. In the first instance, the rights granted to blind and disabled people were symbolic social rights, which did not entail any additional costs for the French authorities and did not confer any economic or occupational rights to the persons concerned. Indeed, the governments of the colonies adopted legislation on the social protection of blind people in 1947 in Algeria, in 1954 in Madagascar, and between 1953 and 1956 in the FWA. In all these territories, blind people thereon had the right to a disability/blindness card, which entitled them to reserved seats on public transport, and the right to carry a white cane. No additional educational or vocational rehabilitation infrastructure was created in the colonies concerned.

On 20 December 1954, the French authorities adopted a decree instituting social protection for physically impaired people in overseas territories. In the FWA and Madagascar, severely disabled people were entitled to a disability card that gave priority to access to reserved seats on public transport, similar to what blind people and disabled war veterans already had. In these two territories, no specialized educational or vocational rehabilitation centres were created for the physically impaired in this period. In some territories, the severely disabled also benefited from an exemption from personal taxation.

However, the case of Algeria differs from the other two colonies, as in Algeria blind people also benefited from the right to a modest pension and an allocation of work from 1952, following an intense political struggle. Algeria was also distinguished by the existence of a residual provision of vocational training for physically impaired people from the 1950s, as shown in (Table 4.1).

The French authorities tried to promote social policies with an imperial dimension at different times according to the categories of impaired populations considered: at the end of the First World War for disabled war veterans; from 1931 for leprosy sufferers; and in the 1950s for blind and other physically impaired people. The French Empire's policy of assisting disabled war veterans was one of the few imperial social policies that provided economic protection for the colonized populations in the colonies studied. For blind and physically impaired people, the French authorities, for the most part, promoted symbolic social policies without devoting significant resources to them. For a long time, the imperial authorities left blind and disabled civilians in the FWA and Madagascar without any social protection. The fate of these people depended solely on the solidarity of the family or the local community, the goodwill of charitable individuals, and the devotion of missionaries. Nonetheless, in order to survive, physically impaired and blind civilians in these territories usually resorted to begging or other ad hoc alternatives such as singing for money and selling their handicrafts on the street.

II. A Great Diversity of Actors Involved, with Diverging Interests

This section examines the actors involved in providing assistance to disabled populations. Policies to assist disabled people were, as argued by Lagroye, Francois and Sawicki, in a different situation, the result of a 'set of evolving actions, decisions, interactions and power relations' between multiple actors with extremely unequal resources. [START_REF] Lagroye | Sociologie politique[END_REF] It is argued that many actors participated jointly in all policies to assist injured workers, blind people, and those who were physically impaired. These included metropolitan ministries, parliamentarians, colonial governors, senior officials, doctors, missionaries, associations of disabled people, representatives of private enterprises, and indigenous populations.

A. Physically Impaired People's Associations with Variable Powers and Ranges of Action

With regard to disabled people's organizations, there was considerable unevenness between colonies. Since 1920, there were many associations run by blind people in Algeria, while there were none in Madagascar during the colonial period and only one in the FWA which was created in 1958 also included physically disabled and elderly people. There were associations of injured workers in Algeria, but no such associations were identified in the other territories. Similarly, it was only in Algeria that several associations of civilian physically impaired people appeared from the 1920s onwards. But the first associations, the Amicale des chanteurs et musiciens infirmes de la ville d'Alger [Friendship of Disabled Singers and Musicians of the City of Algiers] and the groupement des béquillards, invalides et paralysés d'Oran [Group of those who walk on crutches, invalids and paralysed people] were not politically active until the 1950s, the former being involved in organizing music concerts and picnics and the latter in distributing food and occasional assistance (birth grants, medical care assistance). [START_REF] Fr Anom ; Brégain | Résolution of the Groupement des béquillards, infirmes et paralysés civils d'Oranie[END_REF] The other associations that formed in the early 1950s (notably the Association algérienne des grands infirmes civils [Algerian Association of seriously disabled civilians] (1952) later renamed the Association des paralysés d'Algérie et des grands infirmes civils [Association of the paralyzed from Algeria and the seriously disabled civilians]) were heavily involved in politics. While associations of blind people and other physically impaired people brought together French and indigenous people from all social classes, those of a national scope were systematically led by French citizens.

In Algeria, and less frequently in other colonial territories, associations of blind people demanded equal economic, social, professional, and educational rights with those of the metropolis. 18 In the 1920s, a group of injured workers in the Department of Algiers claimed the same rights as those held by the injured workers of the metropolis. 19 Associations of impaired civilians often asked for economic benefits similar to those received in the metropolis through the organization of rehabilitation and accommodation centres. The delegate of the Algerian section of the Fédération nationale des malades, infirmes et paralysés stated that 'our comrades in North Africa too often feel forgotten, that they are considered second-class citizens. (…) Today they are simply asking to be treated like their comrades in the Metropolis'. [START_REF] Vivre | Organe de défense des blessés du poumon et de lutte contre la Tuberculose[END_REF] The Association des paralysés d'Algérie et des grands infirmes civils, the Soutien social and the Groupement des béquillards, invalides et paralysés d'Oran militated for the application in Algeria of the laws on the social protection of blind and severely disabled civilians adopted in the metropolis (law 49-1094 of 2 August 1949 and law of 19 April 1952). [START_REF]Archives of the wilaya of Algiers (DZ, AWA[END_REF] Severely disabled people wanted the same economical support as was provided for blind people (which included pensions, the right to free urban transport and medical assistance, exemption from radio tax, and the right to vocational rehabilitation).

The demands of the Algerian associations were relayed by the associations of the metropolis (Fédération Nationale des mutilés du Travail, Fédération nationale des blessés du poumon et des chirurgicaux, Union Générale des Aveugles et Grands Infirmes, Union nationale des sourds de France). In their struggle, associations relied on distinct allies according to the category of their disability. Unlike others, injured workers obtained the support of the workers union (Confédération Générale des Travailleurs). Blind people benefited from the support of colonial doctors and Algerian deputies. 22 The association of the physically impaired people of Algeria were supported by leading Muslim political figures (Chérif Sid Cara and Nafissa Sid Cara); by several Algerian deputies, including some Muslims and Kabyle (Pierre Lafont, Alice Sportisse, Mostefa Benbahmed, Ali Ben Lakhdar Brahimi, etc.); more generally by socialist parliamentarians; and by the Union régionale des oeuvres privées sanitaires et sociales d'Algérie. This political support did not, however, allow new social measures to be adopted. A bill (No. 10-156) presented in the French Assembly in February 1955 aimed at allowing Algeria's severely disabled persons to benefit from the provisions made for blind Algerians was not adopted. The French authorities strongly opposed it, considering that this decision was a matter for the Algerian Assembly.

In repressive colonial contexts, associations for disabled people had a repertoire of action limited to non-violent and generally non-subversive actions: political and administrative negotiations, pressure on parliamentarians, and public questioning of political leaders at congresses. However, even here, the use of political and administrative negotiations was hampered by the geographical distance between them and the metropolitan ministries that had the decision-making power. The leaders of the associations of blind people in Algeria had a wider repertoire of action than the others. They did not hesitate to go to Paris to negotiate directly with civil servants and political leaders, and they invited them to come to their national congresses. They also denounced the injustices linked to the non-application of metropolitan legislation in Algeria. During the inter-war period, these criticisms were subtle, intertwined with the evidence of loyalty to the authorities. After the Second World War and the adoption of the Lamine Guèye law in May 1946, which abolished the distinction between French citizens and Muslim subjects in Algeria, criticism became more discursively aggressive. The intense mobilization of blind people in Algeria led to major social achievements (including establishing the right to a pension for the blind). As early as 1953, the Association algérienne des grands infirmes civils vehemently protested on the discursive level 'against such a deficiency which deliberately sacrifices paralytics who need the help of a personal care assistant'. 23 In the FWA, the leaders of the Union des paralytiques, aveugles, vieillards et nécessiteux also used only letter-writing approaches, but did not hesitate to call on intergovernmental organizations such as the International Labour Office (ILO) to help establish a rehabilitation centre. [START_REF] Fr Nap | Article entitled 'Vieillards et nécessiteux à Dakar[END_REF] Officials of the ILO's Vocational Rehabilitation Service could not take up this request, to their great regret, due to the lack of an official request for technical assistance from the French government. [START_REF]Appel et le Cri de la misère[END_REF]

B. Public Authorities Were Concerned about Saving Money and Motivated by the Gain of Political Support

The metropolitan ministries often disagreed on the relevance of the application of social legislation in colonies. The Ministry of Health in metropolitan France was in favour of applying the legislation on blind people in colonies but did not agree to assume the financing of the measures taken. The Ministry of Colonies (until 1946) and then the Ministry of Overseas France (1946-1959) remained very cautious about the possibilities of applying social legislation in favour of various categories of disabled people in colonies. For this Ministry, the decision to apply these measures was all the more complex as administrative issues (legislative measures that varied according to territories), political issues (political pressure from associations), incomplete statistical data (including the number of beneficiaries), and economic, social and cultural issues (surrounding the applicability to each local society) became intertwined. These ministers often faced opposition from the Ministry of Finance, which wanted to reduce expenses generated by these measures as much as possible for the French state. When asked about the possibility of covering the risks of accidents at work in overseas territories in the 1950s, the Ministry of Finance responded that it was in favour of a funded system managed by private insurance, so that the public authorities would never have to pay for potential deficits. [START_REF] Fr Anom | The Ministry of Overseas France to the HCs of the Republic in the Overseas Territories. 27 Brégain[END_REF] The Ministry of Finance agreed to issue pensions for disabled war veterans but refused to increase these pensions at the end of the 1920s and categorically refused to finance pensions for blind people, arguing that this was a choice to be made by each colony. 27 Due to the negative responses of the Ministry of Finance, in 1952 the Ministry of Overseas France encouraged the governors of various colonies to adopt the legislation granting rights to blind people without incurring additional expenses. 28 It mentioned the possibility of creating training and re-education centres for blind people, but only 'in cases where the number of blind people likely to benefit practically from such measures justifies the use of these means'. 29 Similarly, in 1954, the Ministry of Overseas France favoured measures with no budgetary consequences for physically impaired civilians, with the governors of the colonies at liberty to develop educational or reeducation centres as they saw fit. The Ministry of Colonies (until 1946) and then the Ministry of Overseas France (1946-1959) generally consulted the opinions of local governors to determine the extent of needs and the relevance of these social laws at the local level. This decentralization of decision-making was then common in the administrative management of the Empire because of the distances and 'the very limited number of administrators in relation to the vastness of the territories to be administered'. 30 Local governors had extensive regulatory powers. They were also free to execute metropolitan texts quickly or not because they were not bound by any time limit in the promulgation of enforceable decrees. 31 Local governors were also concerned about the cost of possible policies to assist various categories of disabled persons and the consequences on local economic life. Local governors generally minimized the needs and refused responsibility for expenses incurred. In the field of work-related accidents, the Governor of Madagascar expressed reservations about the application of workers' compensation legislation, citing the poor willingness of insurance companies to cover risks and the cost for start-up companies in Madagascar. The Governor of the FWA invoked the fear that indigenous people would voluntarily injure themselves in order to receive compensation. The absence of local industries and the very small number of European workers were also raised as concerns. [START_REF] Le | Histoire du droit du travail dans les colonies françaises[END_REF] The Governor of the FWA played down the need to create a school for blind children by invoking the small number of young blind people 'able to benefit from educational courses' and the considerable expenses that a school would entail. Instead, he wrote that 'It would be preferable to direct the blind of Upper Volta to the educational centres that may exist in the neighbouring territories'. 33 It was only under intense associative and political pressure that local governors granted measures in favour of disabled people with budgetary implications and that too only in exceptional cases. On 2 July 1952, the Algerian Assembly approved Decision No. 52-038 on the social protection of blind people, which legitimized the granting of a pension to blind nonworking people and a compensation allowance to blind workers. In order to limit the colony's expenses, the blind civilians received a pension 'the amount of which is equal to one-sixth of the allowance paid in Algeria to old wage earners in the non-agricultural sector'. 34 This pension was substantially increased (that is by 150 per cent) 'when the blind needed the constant help of a third person'. Two years later, associations of the severely physically impaired in Algeria requested for the application of metropolitan social legislation in their favour. In response to this, the Algerian colonial administration studied in 1955 the possibility of granting an allowance equal to that of the blind for all severely physically impaired civilians. However, while the Director of Health and Family was in favour, the Director General of Finance was against it: After having blackened the table of expenses generated by such a measure, the Director of Finance informed the General Governor of Algeria that it constituted an "excessive burden [on Algeria's budget] in view of the advantages that would result from it (…) it seems to me sufficiently onerous for me to wish to limit its effects by rejecting, from the outset, the proposals presented". 35 Following this letter, the draft legislation was abandoned. The administration left it up to the associations to solve the 'problem' of physically impaired civilians. As of early 1953, it merely authorized calls for public generosity during the National Day of the Physically Impaired in the three Algerian departments for the benefit of physically impaired people's associations. A few years later, multiple political pressures on parliamentarians led to the reintroduction of a legislative project granting allowances to severely disabled people in Algeria. The authorities looked only at a step-by-step reform, initially only granting allowances for persons with a disability of at least 80 per cent and in need of a personal-care assistant. 36 From the outset, therefore, the payment of an allowance to disabled persons with a disability of less than 80 per cent was excluded. But even with this restriction on the beneficiaries envisaged, the Delegate General in Algeria indicated at the end of 1960 that financial imperatives prevented him from granting benefits similar to those held by the blind for other severely disabled people. 37 The government gave priority to other expenditures contributing to productivity and the improvement of the labour market. Moreover, in the following two years, the Algerian administration did not devote any budget to the development of vocational rehabilitation for blind people, contrary to what was provided for in the development plan.

C. Formalization of the Right to Compensation for Indigenous Injured Workers

In Algeria, many actors opposed the formalization of the right to compensation for indigenous injured workers. They cited the spectre of additional costs in compensating indigenous polygamous employees who were victims of accidents, as well as the fear that such a measure, if it were reserved for the French, would harm them because hiring foreign workers would be less costly in terms of insurance. [START_REF] Lekeal | Pacifier par le droit social? L'applicabilité de la législation ouvrière française en Algérie: 1895-1921[END_REF] A well-known lawyer, Jean Thomas, invoked the over-exposure of indigenous people to the risk of accidents, which he believed was their 'idleness' and their alleged propensity to be injured in order to receive a pension, in order to prove the inadequacy of this legislation in Algeria. 39 In doing so, he tried to 'return the republican egalitarian logic to the benefit of employers'. 40 But, despite this, the Algerian government finally adopted the legislation on industrial accidents in 1919.

In the FWA and Madagascar, the financial implications of the law on working accidents for employers meant that the Chambers of Commerce of Saint Louis of Senegal and Tananarive, the Chambers of Agriculture, and industrial associations all opposed the application of the legislation on industrial accidents for indigenous persons. In evidence, they cited many racialized claims such as those concerning the clumsiness of indigenous people, their perceived laziness, their propensity to injure themselves in order to enjoy a pension; the absence of mechanical work in the colonies; the absence of insurance companies; and the shortage of doctors and civil servants to supervise the application of the law. 41 However, Madagascar's chambers of commerce did accept the extension of the legislation on working accidents to Europeans. In September 1925, a decree on indigenous work in Madagascar granted a daily allowance for one month to any indigenous accident victim. 42 In 1937, a law related to accidents was approved in Madagascar, which granted a right to compensation only to indigenous persons. Europeans were already protected by case law.

In the FWA, the French Colonial Union categorically opposed the adoption of legislation on work-related accidents, but Governor General De Coppet, a Frenchman close to the socialists, bypassed this opposition and issued a decree on work-related accidents on 2 April 1932. The French Colonial Union then continued its struggle to avoid the application of this decree by invoking the economic crisis and the cost of such a measure. 43 This pressure contributed to the delay in the adoption of the implementing decrees, which were finally adopted on 30 July 1936. Two decades later, the FWA and Madagascar underwent new transformations in the policies of compensation for work-related injuries, by choice of the metropolitan authorities. In 1956, during discussions within the French High Labour Council on a new draft legislation on occupational accidents in the overseas territories, the employers' representatives were in favour of the financing of compensation by private insurance companies, but the workers' trade unions opposed it. As African policymakers were also hostile to the use of private insurance to cover the risk of accidents at work, the French authorities chose a 'simple and inexpensive' compromise solution, deciding to link the coverage of the risk to the Caisses de compensation des prestations familiales [Family benefit compensation funds]. [START_REF] Fr Anom | Minister of Overseas France to the HCs of the Republic in WFA[END_REF] During the period studied, the balance of power between various actors shifted in favour of the associations of blind people, who, after lengthy mobilizations, managed to get the public authorities to bend on certain points. Nevertheless, public authorities remained concerned about saving money and only agreed to act when they were convinced that spending would be contained and that it would contribute to bringing political benefits to the colonial order. The balance of power was changing to the detriment of French settlers in the colonies, who had to accept that their indigenous workers had the right to a meagre compensation in the event of working accidents. In constant contact with the indigenous people and mastering their languages, the missionaries remained powerful and central actors in health care for the blind and physically impaired in the colonies studied until the end of the colonial period. Missionaries perceived themselves both as actors of the 'French civilizing mission' and as actors of evangelization. Their weight was all the more important in the FWA and Madagascar because they embodied French social action, which colonial governments were reluctant to develop.

Conclusion

This chapter has demonstrated that policies intended to assist disabled people in the French Empire were very heterogeneous and varied according to the territories, the categories of disabled people assisted, and their legal, racialized, status (French/indigenous). Major ethnic inequalities can be noted, with indigenous people often receiving distinct and discriminatory treatment compared to the French. With the exception of disabled war veterans and the case of the blind in Algeria, these policies rarely and/or belatedly reached the rank of priority policies in the eyes of the imperial authorities and were not seen as deserving substantial financial investment.

These policies evolved over decades and according to the extent of the social problem with which they were associated (blindness, occupational accidents, etc.). But above all, they were contingent on the way in which political pressures were exerted at different levels (local, national, international) at different moments. While various actors present in the colonies and the metropolis played a fundamental role in constructing policies to assist disabled people, there was also a transnational element to this. For example, ideas, people, information, and equipment circulated transnationally. Similarly, the role of international organizations and the role of standards set at international congresses in driving these policies and their characteristics should not be underestimated. On the one hand, these international conferences sometimes invited the imperial authorities to develop social policies in their colonies, such as the resolution adopted in 1949 by the International Conference of Workers for the Blind encouraging empires to develop policies to prevent blindness and protect the well-being of the blind throughout their colonial territories. 45 On the other hand, it can be seen that international organizations played a major role in challenging and convincing the French imperial authorities to initiate a policy of protecting the injured workers (end of the 1920s by the International Labour Organization), combating imperial-scale leprosy (1930s by the Health Organization), and providing social protection for the blind and physically impaired in the colonies (1950s by the United Nations). 46 Along with these transnational and international trends, the specificity of the place was also an important factor. Algeria was the most favoured colony in terms of services provided and economic rights granted to disabled people. This can easily be explained by its special legal status (constituted by three French departments), but it also reflects the considerable political pressure exerted by the associations of disabled people in this territory. On the other hand, the territories of the FWA (excluding the Four Municipalities of Senegal) and Madagascar were disadvantaged in terms of the services provided. As a result, even at the end of the 1950s, and in the absence of professional skills, many blind and disabled civilians in these territories were forced to seek private or community charity, a stigmatizing process since the beneficiaries must demonstrate their poverty in order to receive it.

This chapter has sought to reinforce several recent dynamics in the literature on disability history. It has shown the need to move away from caricature approaches to disability policies during the colonial period, by demonstrating the weight of the political demands made by disability associations, the existence of actors who supported or opposed their demands, and the refusal of the colonial authorities to generalize a policy of economic assistance to disabled people, preferring to leave their fate to depend on public generosity and family solidarity. This chapter also highlights the relevance and utility of comparative approaches (between different categories of disabled people and between different colonial territories), since they can prove the existence of unequal and differentiated treatment between different categories of disabled people and also show the extreme heterogeneity, complexity, and weakness of imperial policies around disability in the French Empire.

Table 4 . 1

 41 Heterogeneity of Policies for Disabled People in the FrenchColonies, 1918-1962.


Merve Nur Tunc
email: merve-nur.tunc@inrae.fr

Rosa Del Campo

Steven Porter

Florence Dubois-Brissonnet

Romain Briandet

Rut Carballido-Lopez

Resistance to the Last-Resort Antibiotic Colistin in Pseudomonas aeruginosa

INTRODUCTION

Pseudomonas aeruginosa is among 'the 3 most critical antibiotic-resistant priority pathogens list' of the World Health Organisation (WHO) 1 . Besides being resistant , it causes several chronic infections including biofilm formation in cystic fibrosis patients.

Desease cause by Pseudomonas aeruginosa infection [START_REF] Proctor | Potential Therapeutic Targets for Combination Antibody Therapy against Pseudomonas aeruginosa Infections[END_REF] .

Colistin (polymyxin E) is an antibiotic used as a lastresort treatment for multidrug-resistant (MDR) Gram-negative infections including pneumonia and P. aeruginosa. As a last resort antibiotic, it is in the WHO list of 'the critically important antimicrobials for human medicine' 1 .

Illustration of Colistin mode of action, resistant/tolerance mechanisms of P. aeruginosa 3 and new combination therapies.

OBJECTIVE

Recent studies show an increase in the number of P. aeruginosa isolates less sensitive to colistin in chronic infections [START_REF] Mohapatra | Polymyxins, the last-resort antibiotics: Mode of action, resistance emergence, and potential solutions[END_REF] . Drug A is a new candidate to restore colistin sensitivity in P. aeruginosa. It is the mainstone of the project: it has no antimicrobial activity on its own in P. aeruginosa but has synergistic antibacterial activity with colistin. Preliminary results show that it restores sensibility to colistin in resistant strains. The main aim of the project is hence to decipher the molecular processes involved in the colistin-resensitivation mechanisms to better control it..

Why is the Colistin

II. Mode of action in planktonic cells

Gas Chromatography -Mass Spectrometry (GC-MS) Conditions that will be observed in single cell.

Lattice-Structure Illumination Microscopy (SIM)

• Effect on the growth rate

III. of action in biofilms

FIRST RESULTS

I.Minimum Inhibitory Concentration (MIC)

Determination for 69 clinical and control strains. For P. aeruginosa the breakpoints of colistin is set at Sensitive (S) ≤4, Resistant (R) >4 mg/L. As a control, aztreonam is used and its breakpoint is 16 mg/L. > There is no significant differences when Drug A is added.

CONCLUSION/ PERSPECTIVES

Even though the bactericidal mechanism of colistin is not fully known yet, several hypotheses could be involked to explain the synergistic interaction of colistin and drug A .

The first results suggest that the leading cause of this synergistic interaction is not related to fatty acids modification.

The first steps were taken for the construction of the strains required for the test of bacterial membrane structure and permeability. To check these hypotheses; Lattice-SIM, 4D-LSC Microscopy and SEM, cytometry techniques will be used, fluorescent tools will be developed and analyses of these data will be done.

  -Drug A synergy important? Hypothesis METHODS I. Developing a toolbox for P. aeruginosa fluorescent imaging a. Fluorescent Colistin • To monitor cellular uptake • Determine diffusion rate in the presence and the absence of drug A • FADDI-285 • FADDI-286 (Yun B et al., 2017) 5 b. Detection of fluorescently-labelled LPS • To solve interaction between drug A , colistin and LPS c. Engineering P. aeruginosa strains • Fluorescent protein addition • Gene deletion

•

  Effect on biofilm formation • Biofilm structural dynamics • Local expression of resistance / tolerance genes with fluorescent reporters 20 hours biofilm PAO1-fix Live/Dead Staining. Left to right, untreated control, 2 hours incubated with 8 mg/L colistin and 3 hours incubated with 2 mg/L colistin + 16 mg/L Drug A PAO1-fix biofilm z-stack images. Green refers to all population (Syto9), red refers dead suppopulation (Propidium Iodide).

>

  Drug A decreasing MIC value of colistin for both sensitive and resistance P. aeruginosa strains while it has no effects on aztreonam MIC value. II. Membrane Fatty Acid Profiles of PAO1-fix and clinical P. aeruginosa strain with/out and different concentration of Drug A .

>

  A Closer look to Hydroxylated Fatty Acid Profiles < > More clinical strains must be checked to see if hydroxylated fatty acids are important for colistin resistance/tolerance.

ACKNOWLEDGEMENTS

The project is conducted within the ProCeD and B3D Teams of Micalis Institute, INRAe, FR and Merve Nur TUNC ( PhD student) is supported by Paris Region (Region Ile-de-France, DIM1HEALTH). This poster presentation is granted by BioProbe interdisciplinary initiative of Université Paris-Saclay.


Donal Bissainte
email: dbissainte@ufl.edu

IMMIGRANT FOOD ENTREPRENEURS: THE RESILIENT GROUP THAT ENHANCES THE SOCIAL IDENTITY OF IMMIGRANT COMMUNITIES IN FLORIDA

Introduction

Small businesses, described as the "lifeblood" of the U.S. economy, contribute significantly, generating two-thirds of new jobs and 44% of economic activity. Immigrant-owned businesses, comprising 13.2%, outpace U.S.-born counterparts at 1.8%, with notable success in categories with sales over $500,000. Florida ranks fifth in the nation for dependence on immigrant entrepreneurs, according to surveys from 2007 and 2020. Immigrants have high-risk tolerance that aids their success in complex business environments. Understanding their choice to enter the food sector sheds light on U.S. entrepreneurship, revealing traits like self-selection influencing their risk-taking in private ventures. Neighborhoods and immigrant enclaves also support self-employment and social networks among immigrants.

Research questions

•Why invest in grocery stores and food trucks?

•How do they meet entrepreneurial challenges and succeed in their businesses?

•How do they maintain family and community relationships?

Methods

Theoretical Framework

• Explanatory single case study

• Referral sampling for 14 semi-structured interviews

• Qualitative data analysis by coding (NVIVO) and using content analysis for the interviews • Localization of Immigrant Enclaves and Ethnic grocery stores (GIS)

Participant characteristics (N=14)

Ethnic grocery stores and immigrant enclaves in Florida

Results OF THEMATIC ANALYSIS Conclusions

The entrepreneurial motivations of immigrant entrepreneurs in Florida are the desire to serve the community, the pride in sharing their cultures and cuisines, and financial freedom and selfemployment

Immigrant entrepreneurs make personal sacrifices and overcome logistical obstacles to build their ENDURANCE and DETERMINATION Immigrant food entrepreneurs in Florida place significant value on their relationships with their families.

They establish personal connections with their customers, offering a sense of familiarity and a personal touch that customers appreciate

Challenges Number of food businesses

Non-support from the cities 7

Shortages or out-of-stock situations 6

Lack of available workforce 3

Understanding and complying with regulations 3

Building clientele 8

Financial constraints and importation process 5

Table 1. Main Challenges of small food businesses

This research delves into the significant role immigrant-owned businesses play in the U.S. economy, focusing on Florida's diverse food system. It explores the strategies, challenges, and relationships of immigrant food entrepreneurs. These entrepreneurs exhibit determination, adaptability, and diverse aspirations, aiming for success through strategic product ordering and financial goals. Challenges faced include city requirements, inventory issues, and financial constraints. Despite these hurdles, they display resilience, continuously improving their businesses by diversifying offerings and engaging with the community. Family involvement is pivotal, providing support in operations and finance. Immigrant entrepreneurs prioritize community relationships, fostering connections with customers and supporting local causes. The research underscores their resilience and emphasizes the need for support systems to empower these entrepreneurs and integrate them into the local food economy.

ABSTRACT

• The several reasons why immigrants run grocery stores and food trucks in Florida are based on love and passion for food business, financial freedom, and family legacy. They want to promote their culture and get connected with their community. • The motivations revolve around the idea of entrepreneurial independence and the desire to have control over their time. • They develop the personal resilience through entrepreneurial challenges by believing in whatever they do, they y strive to be the best and achieve even greater success than what they have already attained. • Immigrant food entrepreneurs display remarkable determination, endurance, and adaptability in overcoming obstacles. • Despite the challenges, these immigrant entrepreneurs demonstrate a relentless pursuit of improvement and a belief in achieving greater success. • They place significant value on their relationships with their families and communities.

• They establish personal connections with their customers, offering a sense of familiarity and a personal touch that customers appreciate.

dobissainte@gmail.com dbissainte@ufl.edu Contact

Figure 1 .

 1 Figure 1. Theoretical Framework of Immigrant Enclave Theory and Adult Personal Theory.

Figure 2 .

 2 Figure 2. Typology of the food business and immigrant enclaves

The Haitian government


Characterizing the dynamics of the Viedma glacier through remote sensing

Basile Boland and Davidson Saint-Louis. Université catholique de Louvain, Belgique

Glaciers are critical components of Earth's hydrological cycle and are important indicators of climate change [2]. They serve as reservoirs of fresh water and their melting can contribute to sea level rise. Therefore, monitoring glacier dynamics can help improve climate prediction models and provide a better understanding of temperature evolution in a region. One key parameter for estimating changes in ice volume in response to global warming is glacier surface velocity. This study focuses on estimating the surface motion of the Viedma glacier and its effective surface between 2018 and 2022. To distinguish ice from snow, the NDSI and NDWI indices have been computed. This allows for further determination of the effective glacier extent and the movement of the front-line.

Problem, context and objectives

The study area is located in south-west Argentina, close to the Chilean border, and is part of the Lake Viedma valley glacier, which covers an area of 13,000 square kilometers. The Viedma glacier is one of the largest and most dynamic glaciers in the Andes, with a reported loss of 10-20% of its total surface area due to melting [1] whereas it is considered as a strategic water resource for the Pentagonia region. This study focuses on a specific area of 50 km² centered around the end of the Viedma glacier, where it flows into the Lake Viedma, to better understand both its spatial and temporal behavior. To achieve our objectives, we utilized two sets of images. The first set consisted of Sentinel-2 images, which provided spectral information necessary for calculating NDSI and NDWI in the visible, NIR, and Short-Wave Infrared (SWIR) spectrum. The second set comprised Sentinel-1 images that allowed us to determine the velocity of the glacier over a two-month period. We obtained the data from Luxembourg Space Agency (LSA) and processed it using the Python environment and SNAP software for multispectral and radar images, respectively. To reduce the impact of snow and obtain a more accurate estimate of the glacier's velocity near the front zone, we collected data during the same and warmer period of each 12-month cycle.

Study area

Data sources

References 4. Method

Conclusion and perspectives

This study aimed to map the extent of Viedma glacier over a 4-year period, from December 2018 to January 2021. In this research, 4 satellite images had been used to map the glacier area via the Normalized Difference Snow Index (NDSI), which is based on the visible and short-wave infrared part of the electromagnetic spectrum. The NDSI formula had been applied to the Green and SWIR bands of Sentinel 2 imagery to generate glacier extent map. The latter had been then compared with reference data from the Global Land and Ice Measurement from Space (GLIMS) for validation.

In addition, the water/glacier front-line and surface flow speed have been estimated to monitor changes in the frontal zone between the glacier and Viedma lake. The Normalized Difference Water Index (NDWI) was computed and help better identify the front line between the water bodies.

Surface flow speed is an important indicator of glacier dynamics, and a pair of sentinel-1 radar images, on November 25 th , 2022, and January 12 th , 2023, was used to determine the surface flow speed of Viedma glacier. The offset feature-tracking algorithm allowed the computing that metric using the version 9.0.0 of SNAP software.

Evaluation of temporal dynamics of the Viedma glacier in the Patagonia region reveals:

• A general trend of glacier retreat in the area • A retreat length of 750 meters from 2018 to 2021

To ensure the accuracy of the results, the outline of the Viedma glacier obtained from Sentinel-2 images is compared with GLIMS data and similar research.

Results show a difference of 13 km² in the glacier's boundaries in 2021, indicating that the front line has retreated from one year to another.

This study highlights the capability of Sentinel images to monitor the Viedma glacier in the border of Argentina and Chile. By evaluating the temporal glacier inventories between 2018 and 2022, we found evidence that the selected glacier is retreating, a behavior that may be associated with the effects of climate change in the region. Although the study period is short and the acquisition date of GLIMS data isn't certain, several observations strongly indicate that the glacier is experiencing significant retreat and is highly active. This is supported by the following evidence:

• A retreat of 2.5 km between the GLIMS data acquisition (assumed to be 2016) and 2018,

• A retreat of 750 m between 2018 and 2021,

• The observed range of the glacier's velocity up to 3 m/day.

It is important to continue monitoring glaciers, which serve as a sensitive indicator of climate change and a valuable source of fresh water around the world.

Radar data from Sentinel-1 shows :

• Average speeds ranging from 0 to 3 m/day using the offsettracking algorithm • Maximum velocity of the glacier is 3.07 m/day Similar velocities values have been reported for the Viedma glacier [2]. Indeed, glacier velocity is a reliable indicator of glacier volume and, to some extent, temperature.

This finding can be supported by an analysis of elevation data for the glacier area to improve or validate the current results. • Overall results suggest that the retreat of the Viedma may be associated with climate change in the region, but a longerterm analysis using Landsat data is necessary to confirm this statement. Indeed, Sentinel data is available only from 2016, while Landsat data allows for monitoring over a longer period.

Data acquisition

• Images from 2020 were excluded from the analysis due to excessive snow cover. The surface value observed in the graphic results in an interpolation computation.

Results and discussions

Abstract

In the current context of climate change, the study of glaciers is crucial as they serve as indicators of rising temperature. This study specifically focuses on monitoring the Viedma glacier using data obtained from the Sentinel-1 and Sentinel-2 satellites. By calculating the NDWI and NDSI indices, changes in the glacier's surface and its front-line adjacent to Lake Viedma were tracked. The results indicate a retreat of the glacier front by 750 meters between 2018 and 2021. The comparison with GLIMS data confirms a similar trend. The daily average velocity of glacier displacement ranges from 0 to 3 meters, which is consistent with the velocity values reported in the existing literature for this glacier. These findings clearly demonstrate the ongoing evolution of the Viedma glacier over time.

•

  These findings are consistent with similar studies conducted previously in the area [3].

Figure 3 :

 3 Figure 1 : Map of the study area (ROI)


Davidson Saint-Louis. Université catholique de Louvain, Belgique

The methodology workflow (Fig 3) provides a comprehensive overview of the steps involved in this study, with a focus on five main stages:

Abstract: Gully erosion is a widespread form of land degradation throughout the world. In Haiti, it is primarily driven by deforestation and erosive farming practices. In this study, an object-based approach was developed to map gully-affected areas in the Grande Rivière du Nord watershed using high-resolution Pléiades imagery. Metrics such as spectral indices (NDVI, SAVI, NDSI) and elevation-derived data were computed using eCognition software followed by segmentation and object classification. Both Decision Trees (DT) and Random Forest (RF) classifiers were used. The results showed that the RF model outperformed the DT model in terms of overall accuracy (86%), precision (94%), and F-score (92%). The estimated extent of gullied areas using RF was 3.4 km 2 , corresponding to 3.2% of the total study area of 106 km 2 . Spectral indices were found to be the most influential features for gully mapping, followed by shape features and the textural homogeneity index. Elevation data were useful in image segmentation but did not contribute significantly to classification results. By combining field surveys and remote sensing data acquisition, the approach developed can be replicated for mapping gully erosion in Haiti.

Characterization of gully erosion by remote sensing in Haiti:

The case of the Grande Rivière du Nord watershed

Research needs and objectives

Soil erosion and particularly gully erosion is generally recognized as the dominant process of land degradation. In Haiti, soil erosion is primarily caused by human activities but is exacerbated by biophysical factors like rainfall and relief. In the Grande Rivière du Nord watershed in Haiti, gully erosion has significant environmental impacts, damaging infrastructure, filling reservoirs with sediment, and affecting agricultural areas. The main objective of this research consists in assessing the performance of object-based image analysis to detect gully erosion in the Grande Rivière du Nord watershed. More specifically, this study aimed to provide answers to specific questions:

• How accurate is the detection of gullied areas using high-resolution multispectral Pléiades imagery? • What is the spatial extent of eroded areas in the Grande Rivière du Nord watershed?

The study area

In the Grande Rivière du Nord watershed, the municipality of Sainte-Suzanne was chosen (Fig. 1) as the focal point for the methodology development due to its representativity of the whole watershed (680 km 2 ). It is also the main contributive area to the main river of GNR (Grande Rivière du Nord) watershed. The study area covers 106 km 2 .

Results and discussions

After the segmentation step (Fig. 4), a multi-label classification was performed (Fig. 5). Random Forest displays a better Overall Accuracy (0.86) than Decision Trees (0.82). Then, a binary classification was carried out between gullied areas and non-gullied areas (Fig. 6). As shown in Fig. 7, RF performs better than DT in terms of precision (0.94), and Fscore (0.92), while still maintaining a good recall (0.91). Therefore, the RF model appears more suitable for gully detection in Haiti, particularly for GNR watershed.

The results indicate that spectral indices are more crucial than other features (Fig. 8). Specifically, the NDVI comes on top with a score of 0.13, followed respectively by the SAVI, which is close to the NDVI, the mean red reflectance, the NDSI and the maximum difference. These top five features show a large gap with the closest following set.

Materials and method

Conclusions and perspectives

For the detection approach developed, a land-cover classification was performed using both Decision Trees and Random Forest. The accuracy of the classification was checked using a confusion matrix, and results indicate that the Random Forest classifier provides better results than Decision Trees. Results also indicate that 3.2% of the studied area exhibit severe erosion. Although this percentage may initially appear low, further analysis and visual observations reveal that two specific regions are significantly impacted by gully erosion, with one of them experiencing over 50% degradation. However, due to the variability in terms of degradation level, vegetation cover, bank nature, and soil type, the method may need some adaptations before it can be transferred to other regions.

1:80,000

Fig. 1 :

 1 Fig. 1: Geolocation of the study area and the watershed

Fig. 3 :

 3 Fig. 3: Overall methodology workflow of the study


Christ Mane Belizaire

Lederson Gañán-Betancur

Ali Sarkhosh

Philip Harmon

Romina Gazis

In Vitro Antifungal Effect of Essential Oil-Based Biopesticides and Synthetic Fungicides against the Avocado Scab Pathogen Elsinoe perseae

Avocado scab, caused by the fungus Elsinoe perseae, is a major disease in most avocado producing regions with warm and humid Climate 1 . Scab causes aesthetic damage to the peel of the fruits leading to significant post-harvest losses due to fruit rejection at the packing houses 2 . Although this pathogen causes economic losses and restricts the cultivation of soughtafter but highly susceptible Cultivars 3,4 , there are few available management approaches and almost none for organic growers. Our objective was to evaluate the in vitro antifungal activity of three essential oils (thyme oil, 'cinnamon oil, and tea tree oil) and three chemical fungicides (copper hydroxide, propiconazole, and fluazinam) against E. perseae. Six fungal isolates were obtained from infected tissues of the avocado cultivars Lula (n=2), Peterson, and Lima Late. Sensitivity to essential oils was assessed using an amended agar media assay with six concentrations of each essential oil. Colony diameter was used to determine EC50 values and minimal inhibitory concentrations within the tested isolates. Using an amended agar media assay, we determined that thyme oil (250 µl/l) and cinnamon oil (125 µl/l) inhibited E. perseae colony growth completely while tea tree oil only reduced E. perseae growth by 14% at the highest concentration tested (2000 µl/l). Sensitivity tests using synthetic fungicides showed that propiconazole (134 mg/l) completely inhibited the growth of the pathogen while copper hydroxide and fluazinam reduced the radial growth at 84% and 56%, respectively.

Materials & Methods

Fungicide sensitivity: Essential oils and synthetic fungicides Field label rates of ThymeGuard (23 % thyme oil), Cinnerate (60% cinnamon oil ) and Tilt (41.8% propiconazole) completely inhibited (100%) the growth of E. perseae.

• Formulations containing the compounds used in this study should be tested in the field as an alternative strategy for managing avocado scab. • Future field trials are needed to evaluate the efficacy of propiconazole formulations applied as spray for controlling E. perseae in avocado • Data from this study will provide guidelines to avocado producers who expect to adopt organic practices including plant-derived essential oil biopesticides. In vitro assays: determination of (EC50), fungistatic and fungitoxic activity. Six Elsinoe perseae isolates, three essential oils, and three synthetic fungicides.

Results -Fungicide sensitivity test -Essential oils

• Thyme oil has fungistatic activity at ≥ 125 µl/l and fungicidal activity at ≥250 µl/l.

• Cinnamon oil has fungicidal activity at ≥ 125 µl/l.

• Tea tree oil did not inhibit completely (100%) or had fungicide activity against any of the six E. perseae isolates even at the highest concentrations tested (≤2000 µl/l).

Abstract

Avocado scab, caused by the fungus Elsinoe perseae, is an important disease of avocado in most humid, tropical, and subtropical regions where avocados are commercially grown 1,2 Scab causes aesthetic damage to the peel of avocado fruit causing significant post-harvest losses due to fruit rejection at packing houses 3 . Rapid and accurate disease diagnosis is critical for the early implementation of adequate and effective management practices that can mitigate their negative impact on crop production. Unfortunately, scab damage on avocado fruit, resulting from infections of E. perseae, is often confused with similar damage (e.g., scarring) resulting from non-fungal related causes such as thrips, beetles, and mechanical injuries. Avocado scab symptoms on fruits appear as blackish/brownish oval and raised forms of cork scab and are scattered on the skin of the fruit. Symptoms resulting from mechanical damage are localized to a specific part of the fruit while those caused by insects resemble brown leather that usually cover the entire surface of the fruit. We have developed classical resources to facilitate the identification of scab in the field, as well as to facilitate isolation, identification, and storage of the causal agent in the laboratory (from cultures). We also generated visual disease rating scales (leaf and fruit) to facilitate the monitoring of scab incidence and severity so that researchers and growers can make informed decisions on disease management practices (i.e., spray timing). This scale was used to assess the susceptibility of twenty-three cultivars grown in south Florida, resulting in the update of previous data published in 2019 for major green-skin cultivars 4 . The resources intended for the identification of the pathogen have been validated with molecular-based techniques. Among three commercially available DNA extraction methods tested, the genomic DNA extracted from samples (i.e., fruit and leaves) resembling typical symptomatology of scab using the Qiagen-QIAamp Fast DNA Stool kit allowed isolation of DNA from avocado host tissue that resulted in positive detection of E. perseae. The PCRbased assay protocol, which takes less than 24 hours for the detection of E. perseae, can be easily implemented across plant diagnostic clinics, allowing producers to make timely management decisions. Finally, our direct diagnostic protocol, standardized disease rating scales, and novel laboratory resources on the avocado scab pathogen, can be used to further research on this disease and expand our knowledge on cultivar susceptibility, fungicide efficacy, and strain virulence.

Fig 3 .

 3 Fig 3. Antifungal activity of essential oils and synthetic fungicides at label rates of commercial products.

Fig 1 .Fig 2 .1

 12 Fig 1. In vitro screening-Methodology summary.

Quick and accurate diagnosticFig 2 .

 2 Fig 2. Methodology for morphological and genetic characterization.

Fig 1 .Fig 3 .

 13 Fig 1. Symptomatic avocado specimens and isolates on PDA.

Figure 5 .

 5 Figure 5. Disease severity rating scale used to score the level of scab damage on avocado fruit.

Figure 4 .

 4 Figure 4. PCR amplification of the species-specific primers SpF5 and SpR6 using DNA from host tissue .

Acknowledgments

Funding Source: • USDA-NIFA Organic Agriculture Research and Extension Initiative (OREI) • BID-GAFSP-IFAD grant 4359/ GR-HA • PLANT SAFETY, HORTICULTURAL BENEFITS, AND DISEASE EFFICACY OF ESSENTIAL OILS FOR USE IN ORGANICALLY GROWN FRUIT CROPS: FROM THE FARM TO THE CONSUMER • Award: 2020-02141