Agromorphological Diversity among Popcorn (Zea mays. everta) Landraces Grown in Zambia

Abstract

Thirty nine (39) popcorn landraces alongside three (3) check varieties were evaluated for variability and relationships based on 15 agromorphological traits in Kabwe, Zambia during 2019/20 and 2020/21 seasons. A randomized complete block design was used with three replications in both instances. Analysis of variance revealed highly significant (p<0.001) differences among the popcorn landrace populations in some traits such as days to anthesis, days to silking, anthesis-silking interval, 100 seed weight, ear and plant heights.Principal component analysis also delineated these traits as the most important in contributing to the variability among the landraces alongside tassel length. The first two principal components accounted for 71.1% of total variability with PC-1 accounting for 41.7 and PC-2 with 28.4%. Genetic diversity based on discriminant analysis revealed low mean differentiation (D2=0.12) among the landrace populations. The check population ‘Lion popcorn’ had the largest mean genetic distance among the studied populations (D2=0.42) while ZMP 1932 was the most differentiated among the landraces (D2=0.38). Cluster analysis resulted in seven clusters with the clustering mostly based on the relative strength of the popcorn landraces in particular traits such as long A-S interval (cluster I) and high seed weight (cluster VII). Overall, two popcorn landraces were identified for their relatively high genetic diversity index (ZMP 1932 and ZMP 1902). These alongside the check variety ‘Lion popcorn’ can be used to cross with the local landraces as a way of increasing genetic diversity.