Assessment of genetic variation among drought tolerant recombinant inbred lines (RILs) of Indian mustard (Brassica juncea L.)

Abstract

The present study reveals the genetic variation among 225 Recombinant Inbred Lines (RILs) derived from
the cross Rohini X PBR-97 which were evaluated under normal and water stress conditions. Significant
genetic variation was observed for plant height, main shoot length, fruiting zone length, siliqua length, biological
yield/plant, harvest index, seed yield/plant, fibre, phenol, days to flowering under normal conditions while plant
height, main shoot length, fruiting zone length, siliqua length, seed/siliqua, harvest index, phenol, days to
flowering were found to be significant under drought conditions. Heritability estimates were high (>70%) for
main shoot length, siliqua length, seed yield/plant, and phenol content. Seed yield per plant was significantly
and positively correlated with plant height (0.37**), main shoot length (0.19*), fruiting zone length (0.16*),
siliqua length (0.19*), seeds/siliquae (0.16*), biological yield per plant (0.45**) and harvest index (0.61**)
and negatively correlated with oil content (-0.13), fibre (-0.28**). Further, 25 promising RILs were identified
based on seed yield/plant which can further be used in brassica improvement breeding programmes to develop
drought tolerant brassica varieties.