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Cocoa mirids are the main insect pests of the crop in Togo. In order to contribute to a sustainable management of these pests, the present study aimed at analyzing some aspects of the cocoa production system in conventional and organic farming and evaluating the perception of producers on the use of botanical pesticides as a means of control. Thus, a survey questionnaire was administered to 178 producers, including 96 conventional cocoa producers and 82 organic cocoa producers. The producers surveyed occured in 27 villages in the prefectures of Agou, Akebou, Kloto and Wawa. The results showed that about 98% of conventional cocoa farmers and 100% of organic cocoa farmers mentioned mirids as major pests of the crop. The average infestation rate of the plantations was estimated at 40.79 ± 25.72% in conventional cocoa production and 44.93 ± 26.92% in organic cocoa production. The related average losses are respectively 13.09 ± 8.58% and 17.39 ± 10.93% in conventional and organic cocoa production. As a means of control, 98.93% of producers in conventional cocoa production versus 65.06% in organic cocoa production use at least one insecticide. Three (3) classes of chemical insecticides are used in conventional cocoa production: Neonicotinoids (48.15%), pyrethrinoids (41.66%) and organophosphates (10.18%). In organic cocoa production,Azadirachtaindicais the plant most used for mirid control. 31.71% of producers use Neem oil against 17.05% and 15.85% who use its leaves and seeds respectively. Regarding producer adherence, 81.96% of conventional and 91.46% of organic cocoa farmers believe that local plant-based bioinsecticides can help to control cocoa mirids 68.75% and 71.95% of these two respective groups are willing to use them if they are effective and affordable. &nbsp

Les agroforêts à cacaoyers du Togo sont caractérisées par leur faible productivité. L’objectif de cette étude est d’identifier les caractéristiques agronomiques et les facteurs déterminant la faible productivité des cacaoyers. Une enquête a été menée auprès de 385 cacaoculteurs suivie d’une prospection réalisée dans 88 vergers de cacaoyers répartis en quatre tranches d’âge : les jeunes plantations entrant en production (5 à 10 ans), les cacaoyers adultes en pleine production (10 à 20 ans), les cacaoyers vieillissants dont la production est en déclin (21 à 30 ans) et les vieilles plantations (>30 ans). Les résultats ont montré que la tranche d’âge moyenne des vergers est comprise entre 10 et 20 ans. Ces vergers sont essentiellement installés sur les anciens champs de cacaoyers (42,6%) et sur précédent forestier (40,3%) avec du matériel végétal constitué en grande partie d’hybrides sélectionnés (82,9%). Les fréquences de désherbages, des traitements phytosanitaires (insecticides et fongicides) et d’applications de fumure (organique et minérale) sont inférieures aux normes recommandées par la recherche. Les rendements moyens sont faibles et sont compris entre 218,64 kg/ha dans les vieilles plantations (> 30 ans) et 450,77 kg/ha dans les plantations adultes en pleine production (10 à 20 ans). En ce qui concerne les différentes sous zones agroécologiques, les résultats ne révèlent aucune différence significative pour les rendements. Ces rendements varient de 305,76 kg/ha dans la sous zone de plateaux à 376,59 kg/ha dans la sous zone de Kloto-Litimé. Cette faible productivité est liée au faible niveau de gestion et d’entretien des vergers, aux caractéristiques des peuplements cacaoyers et des peuplements associés. Cocoa agroforests in Togo are characterized by their low productivity. The objective of this study is to identify the agronomic characteristics and factors determining the low productivity of cocoa trees. A survey was conducted among 385 cocoa farmers followed by a survey carried out in 88 cocoa orchards and four age groups were considered: young plantations entering production (5 to 10 years), adult cocoa trees in production (10 to 20 years), aging cocoa trees in production (21 to 30 years) and old plantations (>30 years). The results showed that the mean age group of orchards is 10 to 20 years old. These orchards are mainly installed on old cocoa fields (42.6%) and on previous forest (40,3%) with plant material consisting largely of selected hybrids (82,9%). The frequencies of weeding, phytosanitary treatments (insecticides and fungicides) and manure applications (organic and mineral) are below the standards recommended by research. Average yields are low and range between 218,64 kg/ha in old plantations (> 30 years) and 450,77 kg/ha in adult plantations in production (10 to 20 years). With regard to the different agro-ecological sub-zones, the results show that yields vary from 305,76 kg/ha in the plateau sub-zone to 376,59 kg/ha in the Kloto-Litimé sub-zone. This low productivity is linked to the low level of management and maintenance of orchards, to the characteristics of cocoa stands and associated stands.

International audience; In order to quantitatively analyse the spatial pattern of cacao swollen shoot disease, particularly in cases of re-emergence, three experimental plots were installed in a diseased area of cacao cv. Amelonado in Togo. After thorough cleaning and grubbing, the three plots were planted with less susceptible, hybrid plant material. Twenty years after replanting, a survey of healthy, diseased and dead trees was carried out during 2 consecutive years. Data were analysed using Ripleys functions and join counts analysis. The re-emergence of the disease occurred in patches or foci: following analyses with the two statistical methods, diseased trees and dead trees were found to be clearly aggregated on the three observed plots for the 2 years. The observed progress of the disease was not the same on the three plots and seemed dependent on the disease state of the first year: the higher the attack rate of the first year, the faster the disease progression. The use of less susceptible plants helped keep the land productive for 15 years. In conclusion, uprooting of the first infection focus can extend the life of cacao plots.