Heterosis studies for yield and physiological traits in rice hybrids under shallow low land condition

Heterosis and heterobeltiosis were estimated for grain yield, its attributes and physiological traits in 33 cross combinations between rice cultivars (improved and landraces) and three male sterile parents (one wild abortive and two indigenous) generated through Line x Tester mating design, with the aim to develop physiologically efficient heterotic hybrid for this ecosystem. In general, the hybrids performed significantly better than the respective parents. Among the 33 hybrids, six hybrids viz., IR 58025A/OR 1898-18RAU 729-12-44, IR58025A/R 304-34, CRMS 31A/RPHR 203-3, CRMS 31A/IR 68830-NDR-1-1, CRMS32A/RPHR-203-3 and IR 58025A/CHINIKAPOOR, had significant heterosis for yield, flag leaf angle, IInd leaf angle, IIIrd leaf angle and flag leaf area.