Inheritance of photo-sensitivity in pigeonpea

Pigeonpea [Cajanus cajan (L.) Millsp.] is a short-day legume species and the late maturing genotypes are more photosensitive than early types. To generate information about inheritance of photo-sensitivity, this study was conducted under natural artificially extended (16 h) photo-periods using F1, F2 BC1F1 generations. Under photo-period, F1 hybrids showed partial dominance earliness; while in , normal distribution that skewed towards earliness observed. In contrast spread data wide with discontinuities recorded at day 70, 82 103. Chisquare tests, when applied to data, suggested three dominant genes (PS3 PS2 PS1 ) controlled expression photo-sensitivity. These were found operating hierarchical order failing express presence PS3 gene. Similarly absence gene, expressed but it masked . Further, gene only both recessive homozygous state. Hence, proposed genetic model for photosensitivity pigeonpea > photoinsensitive genotype being triple (ps3ps3ps2 ps2ps1ps1 ).