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Termites are considered as important pests of maize plantations in Republic of Benin. However, very little information is available on their assemblage composition, abundance, damages, and on the sensitivity of common maize varieties in Benin. This study aims to fill these gaps and provide baseline for the development of an integrated termite management in maize plantations. Therefore, 60 maize fields across 30 villages located in four agro-ecological zones of southern Benin were prospected using the standardized method of belt transects. In addition, the resistance of five maize varieties to termite attacks was evaluated on-farm during two consecutive seasons (2018 and 2019). Fifteen termite species belonging to 11 genera, 6 subfamilies and 3 families were collected in the prospected maize fields. Four species (Macrotermes subhyalinus Rambur, Coptotermes sjostedti Holmgren, Amitermes evuncifer Silvestri, and Trinevitermes germinatus Wasmann) were found in all agro-ecological zones with A. evuncifer as the most abundant species. High similarity indices of termite assemblages were found between the four agro-ecological zones. Wood-feeders group and species nesting in hypogeal nests were the mostly abundant in all agro-ecological zones. The attack rate of termites in maize fields was 16.9% and did not vary significantly between agro-ecological zones. A. evuncifer and C. sjostedti were significantly the most destructive species on the five evaluated varieties, although Trinevitermes oeconomus Trägardh was most abundant in leaf sheaths; M. subhyalinus and Macrotermes bellicossus Smeathman in the stem; Pseudacanthotermes militaris Hagen and Odontotermes sp. in the roots. Termite damage level to maize depended of the variety. Korga variety was classified as highly resistant to termite attacks; Agbadé kouin winiwini variety as resistant; Igbado tchakpa variety as moderately resistant. While, Elèkpèrè and Forkui varieties were classified as highly susceptible. The three maize varieties identified as resistant to termite attack should be included in the development of an integrated termite management program and in future breeding programs. [ABSTRACT FROM AUTHOR]

Termite (Isoptera: Termitidae) infestation is an important constraint of maize production in Benin. A survey of 300 households was conducted in 2018 throughout 30 villages in Southern Benin to evaluate farmers’ knowledge, perceptions and management practices of maize termite pests using focus group discussions and individual interviews with a semi-structured questionnaire. The results showed that for most of the farmers, maize is the most susceptible crop to termite attacks and the maturation developmental stage having the highest termite abundance and damage. A total of 43 different names of maize termite pests corresponding to 8 species were recorded in the study area. Size and colour were the main criteria used by farmers to classify and identify maize termite pests. Amitermes evuncifer was perceived as the most damaging to maize during vegetative and maturation stages, while Macrotermes bellicosus was perceived by famers (32.5%) as most damaging during seedling and flowering maize development stages. Erratic rainfall was perceived by maize producers as the most important factor favouring termite infestation in maize fields. The majority of the local maize is considered by farmers as susceptible to termites. The use of synthetic insecticides was the main method to control termites. Four of the 20 pesticides used by farmers have active ingredients that have been listed as highly hazardous (class Ib) by the World Health Organization (WHO). Farmers training on the danger and impact of misuse of insecticides on the development of termite insecticide resistance was recommended. The development of an integrated termite management strategy is discussed and the future research for its implementation identified.

The pulse beetle Callosobruchus maculatus Fabricius (Coleoptera: Bruchidae) is an important pest of stored soybean grains. It is imperative to screen out the prevailing genotypes of Beninese soybean cropping systems in order to find out the resistant ones against C. maculatus infestations. The effect of seven grain physical traits (testa thickness, colour, texture, hardness, length, breadth, and 100-grain mass) on the susceptibility of eight soybean varieties to C. maculatus were evaluated in the laboratory. The correlations and contributions of the studied traits were evaluated using correlation path coefficient analysis. The tested soybean varieties showed a variation in physical seed characteristics. A differential susceptibility of soybean varieties to C. maculatus was observed, with the white seeded variety Whéwhé having longest and largest grains was the most susceptible. Based on the Dobie susceptibility index, the Yovoton variety was proved to be resistant to C. maculatus attacks. While, Kecheke, Houeton, Adjaton and Vovoh varieties were classified as moderately resistant to C. maculatus. The correlation analysis indicated that 100-seed weight had significant positive correlation with F1 progeny (r = 0.439), seed consumption (r = 0.467), number of eggs laid (r = 0.295) and susceptibility index (r = 0.453). Path coefficient analysis showed that each seed physical character and its interactions with the others characters influenced soybean grains susceptibility to C. maculatus. Soybean seed thickness showed the higher direct positive effect on soybean susceptibility to C. maculatus indicating that breeding should be done based on this trait to improve soybean seed resistance. [ABSTRACT FROM AUTHOR]