Cytoplasmic differentiation using near-isonuclear polycytoplasmic male sterile lines in pearl millet

Summary Five near-isonuclear polycytoplasmic versions of 81A₁ and two of Pb 402A₃ male sterile lines of pearl millet (Pennisetum typhoides), along with their corresponding maintainer lines (81B and Pb 402B) were studied for 14 agronomic and two disease traits, and for isozymes of peroxidase in anthers and leaves for assessing cytoplasmic differences. Significant differences among isonuclear polycytoplasmic lines of both 81A₁ and Pb 402A₃, having the same genome and variable cytoplasms, were observed for several agronomic traits. Banding pattern of peroxidase isozymes revealed clear cut differences among cytoplasms. The results provide evidence for the influence of cytoplasmic factors on the phenotypic expression of nuclear genes.