Effects of Heterosis for Yield and Yield Contributing Characters in Rice (Oryza sativa L.) under Sodic Soil

Aim: The current experiment was conducted to know the genetic architecture of 12 physio-morphological traits under sodic soil through Line × Tester analysis.

Study Design: The experiment was laid out in randomized complete block design with three replications adopting a recommended spacing of 20 x 15 cm in the field. Recommended package of practices was followed to establish the crop.

Place and Duration of Study: Present investigation was conducted at Farmer Field of village Amwa Bhaluhi of Bhathat Block District: Gorakhpur, India.

Methodology: The hybrids along with parental lines and checks were evaluated through Line × Tester analysis. Lines were used as female while testers were used as male parents where the climate is semi-arid with hot summer and cold winter (sub-tropical) and the soil of experimental field was sodic [ECe = 2.21 (dSm-1 ); pH =9.2]. The water used for irrigating the experimental field was taken from the bore well with pH 9.00 and RSC is 10 meq/L.

Results: An outset on perusal of data for hybrids based on the cross combinations Jhona x Pusa 169 resulted from crossing between parents having high genetic distance showed high positive significant standard heterosis for seed yield. However, the crosses viz., Shriram 434 x PB 1, Halchal x IR 24, Magic x Pusa 169 and Super Moti x Pusa 169, gives sparingly high significant negative standard heterosis for seed yield although their parents having high genetic distance.

Conclusion: These cross combinations merit consideration for extensive testing across space and time in the target environment to verify their suitability for commercial exploitation. The reason for this could have been the linkage of alleles in repulsive phase for biomass and yield. As there was dominance gene action involved, inter se matings followed by recombination breeding might be advocated for the improvement of yield under sodicity. The cross combinations Jhona x Pusa 169 emerged as lines to be recommended for exploitation in hybridization programme to enhance the production and productivity of sodic soil.