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

Abstract

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.

Diallel Analysis of Different Rice Genotypes under Water Deficiency Conditions and Assessing Genetic Diversity Using SSR Markers

“…Mean squares due to parents vs. crosses were highly significant for all the studied traits, except leaf rolling trait under stress conditions, suggesting the presence of significant heterosis for these traits under both environments. Similar results have been reported by Omar et al (2017), Kumar et al (2018) and Shukla et al (2020).…”

Heterosis studies and molecular characterization of three-line rice hybrids

“…Most of the crosses were found to have negative standard heterosis with this check, but two crosses, namely, IR68897A × KMR-3R and Rajendra-3A × RRR-4, exhibited significant positive results. These findings are similar to the results ofShukla et al (2020) andAananthi and Jebaraj (2023).Out of 31 three-line rice hybrid genotypes, 19 hybrids were superior in terms of yield and other related traits. Thus, significant standard heterosis for these characteristics indicated a high level of genetic variability among the hybrids, and the unidirectional distribution of allelic constitution contributed to desirable heterosis in the present study.…”

Estimation of genetic parameters in hybrid and F2 generations of aromatic fine rice

“…A high degree of heterosis was observed in both crosses for the number of tillers hill − 1 and number of effective tillers hill − 1 manifesting superior performance of hybrids (Table7,Xalxo et al 2018). Panicle length is another main attribute of the higher yield of rice.Positive and signi cant heterosis was recorded for panicle length in both crosses (Table7,Shukla et al 2020). The number of grains panicle − 1 and number of lled grains panicle − 1 showed higher estimates of positive signi cant heterosis, which are two crucial factors for increased yield in rice (Table7,Thakor et al 2018 andSari et al 2019).…”

“…. However, to develop dwarf plant types,Sari et al (2019) andShukla et al (2020) emphasized the importance of negative heterosis for plant height. One of the most important yield-determining factors is the tillering habit of a genotype.…”

“…(Table7,Devi et al 2017). Negative heterosis over better parent was recorded for the weight of thousand seeds as it was desired to obtain ne rice grains since ne grains belong to less weight than coarse grains (Table7,Shukla et al 2020).…”