Stability analysis and genotype X environment interaction of cotton seed and fiber yield of some cotton (Gossypium hirsutum L.) genotypes in multi-environment in Mali

Cotton is a strategically important crop for Mali. Mainly used for export, it represents 50–60 % of the value of the country's exports. Genotype by environment interaction study was carried out to identify the most stable cotton genotype(s) and the most desirable for seed cotton yield and lint yield in 35 villages across six different environments(High Valley of the Niger, New Cotton Growing Zone, North Sudan-Sahel, Old Basin, Southern Extension Zone and Zone Sikasso-Bougouni) in a dispersed block design. Where each village represented a block, giving a total of 35 blocks or replications. A combined analysis of variance showed that yields of seed cotton and fiber were significantly affected by environments (p<0.05), but did not reveal any significant difference between genotypes or genotype-environment interactions. The result of GGE biplot analysis method showed that the polygonal view identified three mega-environments (ME1, ME2 and ME3) with three winning genotypes: BRS 293, NTA B149 and NTA L66, respectively, for seed cotton yield. For fiber yield, the winning genotypes were CG1, NTA L65 and BRS 293, respectively. Given that all the varieties tested have a mean fiber yield within the recommended norms, the two promising varieties NTA B149 and NTA L66 with good seed cotton yields and the standard check BRS 293 can be recommended for extension in the environments to which they have been assigned.