AMMI and GGE Biplot Analysis of Yield and Related Traits among Selected Mini-core Pigeonpea (Cajanus cajan L. Millsp.) Accessions

Pigeon pea [Canjanus cajan (L.) Millsp.] is an orphan crop that has remained greatly unimproved in quality and quantity in Africa even though it has great potential of supplying food to the growing population. Its yield is affected by various biotic and abiotic factors and a lack of varieties with broad adaptability to a range of environments. It is therefore important to select accessions that are stable in different environments for yield and yield components. A randomized complete block design layout was used to carry out a multi-locational trial using 107 pigeon pea accessions. Data was taken for the total number of pods per plant at maturity, pod length, seed weight, seeds per pod, and seed yield per plant. Additive main effects and multiplicative interaction (AMMI) with genotype and genotype by environment interaction (GGE) biplot were used to interpret the data. The mean squares for the PCA explained by the first two principal components account for 100% of the G x E interaction. The results revealed that the differences in the yield and yield components across the three locations were mostly due to the genotypes of the pigeon pea and to some extent the genotype by environment interaction. Six accessions were observed to be high-yielding and stable across all three environments.