Maurice Vaissayre's research while affiliated with Cirad - La recherche agronomique pour le développement and other places

... It combines inputs and practices whose objective is to mobilize biological processes for farmers' benefit, which may justify the application of selective insecticides, fungicides, herbicides and fertilizers in a very targeted manner. This is in line with CIRAD's flexible approach to crop protection (Ratnadass et al., 2003b). Still, the ultimate objective should be to minimize such uses, and to ban them when they adversely interact with biological processes. ...

... These have had a lasting success in francophone Africa, providing a limited form of rational crop protection. These decisive technical advances have permitted local variation, as a function of infestation levels and risk, of the quantities of active ingredient required by a range of different intervention programmes (Cauquil and Vaissayre, 1995;Silvie et al., 2001). In different areas and in response to different farmer constraints, extension capacity and insecticide availability situations, the following programmes have been used, forming a sort of progression towards a full IPM programme: ...

... Dans le cadre de l'estimation précoce de la production, ces méthodes sont enfin limitées par l'incertitude sur les conditions de milieu à venir, inconnues au moment de la prévision. Or, les conditions climatiques (Moussa et al., 2003) et phytosanitaires (Deguine et al., 1998) de fin de cycle déterminent une part importante du rendement au travers du nombre de fruits qui pourront arriver à maturité et de leur remplissage, ainsi que la qualité de la production (Ndour et al., 2017). ...

... In the developing countries, where the majority of the producers are often semi-literate and reliant on their own knowledge in the absence of an adequate extension system, the FAO organised, in collaboration with local institutions, programmes of farmer education (Farmer Field Schools or FFS) in cotton, on the system initially developed for the promotion of IPM in rice (Ooi, 2004;Russell, 2004b). These season-long processes of education of groups of farmers in the principles and practices of IPM through a discovery learning process are undoubtedly effective in locally raising the understanding of the cotton agro-ecosystem and in raising yields while reducing pest management costs (Prudent et al., 2006(Prudent et al., , 2007. Ooi et al. (2005) report on the results of the largest of these cotton FFS, in seven Asian countries from 2000 to 2005. ...

... But very few studies have been carried to assess the risk of development of resistance to insecticides with a reduction of dosages and an increase in the number of applications. Vaissayre and Alaux (1996) stated that "insecticides mixtures may decrease resistance selection in a population compared to a constant pressure with a single insecticide". ...

... In the absence of phytosanitary protection, the cotton crop is subject to many attacks by pests, causing crop losses. The cotton crop is subject to strong parasitic pressure induced by many pests, which are responsible for significant crop losses for producers [4,5]. These crop losses varied according to years. ...

... In West Africa, deltamethrin susceptibility in H. armigera was surveyed annually from 1984 (Martin et al., 2002). Pyrethroid resistance was detected in 1996 (Alaux, 1997;Vassal et al., 1997). At the same time, pyrethroid resistance was also detected in South ...

... The over use of synthetic insecticides had destabilized the agro-ecolosystem and led to development of insecticide resistance in pod borer [7] . The pod borer resistance to pyrethroids, organophosphorus and carbamates has been reported in many Asian countries [8][9][10] Africa [11] and Australia [12,13] . Hence, alternate sustainable strategies like host plant resistance in pigeonpea has to be explored. ...

... The cotton or melon aphid A. gossypii, is a polyphagous pest capable of reducing crop yield through direct feeding (Godfrey et al. 1998) and facilitating the transmission of plant diseases (Reddall et al. 2004;Corrêa et al. 2005). In cotton, significant yield reductions due to a lessening in photosynthesis (Heimoana 2012) can occur in addition to aphid honeydew contamination of the open boll lint that will incur a price penalty (Deguine et al. 2007). In Australia, A. gossypii populations can be purposely targeted for chemical control or inadvertently exposed to insecticides directed against other pests such as Helicoverpa spp. ...

... Improvement and security of agricultural production and the difficulties associated with the insect attacks have pushed researchers and farmers towards the use of synthesis chemical insecticide. But these insecticides have proved its ineffectiveness against certain insect pests, according to Brevault and al. (2007), the whitefly, Bemisia tabaci (Gennadius), and aphid, Aphis gossypii have acquired resistance to organophosphate insecticides characters in Cameroon. In addition these pesticides are extremely stable and persistent in the environment, accumulate in living organisms and food chains, are toxic to humans and animals and cause chronic effects such as dysfunction at the level of the reproductive and immune and endocrine systems, as well as cancers, and are propagated in the environment over long distances to remote locations of the sources of emissions (IOMC, 2002). ...