Impact of Genotype × Environment Interaction on Seed Yield and Pod Shattering of Soybean Genotypes in Nigeria

Yield instability and pod shattering are the major problems associated with soybean production in Nigeria. To study Genotype × Environment interaction effects on seed yield and pod shattering behaviour of some soybean genotypes in Nigeria, an experiment was conducted in three (3) environments within the country. In each environment, the experiment was laid out in a randomized complete block design (RCBD) with three replications. During the harvest, pod shattering evaluation was conducted using the sun-dry method. Data were collected on seed yield and pod shattering percentage and analyzed using Additive Main Effect and Multiplicative Interaction (AMMI) and Genotype plus Genotype × Environment Interaction (GGE) bi-plot analyses. Genotypes NCRI SOYAC18, NCRI SOYAC78, NCRI SOYAC9, NCRI SOYAC20, NCRI SOYAC61, NCRI SOYAC22, NCRI SOYAC28 and NCRI SOYAC76, with yields above 1.23 ton/ha recorded high and stable yield across environments. For pod shattering resistance, nine genotypes (NCRI SOYAC3, NCRI SOYAC69, NCRI SOYAC77, NCRI SOYAC29, NCRI SOYAC9, NCRI SOYAC7, NCRI SOYAC67, NCRI SOYAC76 and NCRI SOYAC22) had stable pod shattering resistance across environments. Therefore, only three genotypes (NCRI SOYAC9, NCRI SOYAC22, and NCRI SOYAC76) were stable in both high yield and resistance to pod shattering. Consequently, any soybean breeding programme that involves high yield and pod shattering resistance could consider these three genotypes.