No abstract

Rice is the single largest source of food energy for more than half of the world’s population. Salinity may be a serious environmental constraint to crop production. Salinity screening of twenty rice genotypes were performed at the reproductive stages, in the net house of department of PMB&GE. Phenotyping of the genotypes was done at EC 12dS/m at reproductive stage in net house. Most desirable genotypes days to 50% flowering were IR-68144-2B-2-2-3-1-120, CSR-13, FL-478, NDR-359, AYYAR and NUD-2, SAMBHA MANSURI and MTU-1010; for plant height IR-68144-2B-2-2-3-1-127, NUD-3, NUD-2, NDRK-2008, IR-91171-66-3-2-1-3, SAMBHA MANSURI, TARAMON and  MTU-1010; for panicle bearing tillers/plant FL-478, NDR-359 and SWARNA; for panicle length IR-68144-2B-2-2-3-1-127, IR-91167-99-1-1-1-3, IR-29, FL-478, NDRK-2008 and IR-92953-49-1-3; for spikelets/panicle IR-91167-99-1-1-1-3, NDRK-2008, SWARNA , IR-92953-49-1-3, IR-91171-66-3-2-1-3, IR-83668-35-2-2-2 and MTU-1010; for grains/panicle SWARNA, IR-92953-49-1-3, IR-91171-66-3-2-1-3, IR-83668-35-2-2-2, NDRK-2008 and MTU-1010 for spikelet fertility % NUD-3, IR-29, FL-478, NDRK-2008, SWARNA, IR-91171-66-3-2-1-3 and IR-83668-35-2-2-2; for test weight  NUD-3, NDRK-2008, IR-29 and SWARNA for biological yield/plant AYYAR, TARAMON and NUD-3; for harvest index FL-478, IR-68144-2B-2-2-3-1-120, IR-91167-133-1-1-2-3 and NUD-2; for Na+ NUD-3 and FL-478; for K+ IR-91167-133-1-1-2-3, NDR-359 and MTU-1010; for Na+/K+ IR-68144-2B-2-2-3-1-127, IR-91167-99-1-1-1-3, NUD-3, FL-478, IR-64 and SAMBHA MANSURI; for grain yield/ plant (g) AYYAR and FL-478  were reported highly significant in mean performance for yield and its components traits. Analysis of variance, estimates of phenotypic and genotypic coefficient of variation, estimates of heritability and genetic advance in percent of mean were recorded for all the characters among 20 rice genotypes in saline condition. Molecular analysis with SSR markers differentiates the rice genotypes into tolerant and susceptible based on banding pattern. The tolerant rice genotypes were NUD 3, IR-68144-2B-2-2-3-166, IR68144-2B-2-2-3-1-120, IR68100-2B-2-2-3-1-127, IR-1167-31-3-1-33 and IR-91171-66-3-2-1-3 and susceptible were NDR-359, Taramon, MTU-1010,  Swarna and IR-64. The identified salt tolerant genotypes can be potential germplasm sources for future breeding programmes.

The present investigations were conducted in randomized block design with three replications within the net house of the department of PMB&GE, A. N.D.U.A.T, Kumar Ganj, Ayodhya to estimate the genetic divergence under normal and salt stress conditions involving 20 rice genotypes during Kharif 2018-19, on the basis of relative parameters of D2 values, the clustering pattern of 20 rice genotypes under normal and salt stress conditions were grouped into five non-overlapped clusters. Under normal condition, Cluster III having highest 7 rice genotypes, Cluster II having 5 genotypes, cluster V having 4 genotypes and IV having highest 3 rice genotype. Cluster I having only one genotype. Under saline condition, Cluster I having highest rice 6 genotypes, cluster III having 5 genotypes and cluster II & IV having 4 genotypes respectively. Cluster V having only one genotype. It means the genetic similarity was found in the genotypes were expressed within the cluster and the pattern of distribution of genotypes in various clusters exhibited that topographical diversity wasn't associated with ancestral diversity as genotypes of same countryside were grouped into different cluster and vice-versa. The highest inter cluster distance was recorded between cluster 2 and cluster 5 (26108.030) followed by between cluster 1 and cluster 5 (18550.010), cluster 3 and cluster 5 (15231.860), cluster 4 and cluster 5 (5335.860) in normal condition and in saline condition the maximum inter cluster distance was existed between cluster 4 and cluster 5 (2344.091) followed by between cluster 3 and cluster 5 (2067.610), cluster 2 and cluster 5 (1447.564), cluster 1 and cluster 5 (1238.095). The results showed extensive variation from one cluster to other in respect of cluster means for all parameters, which represented that genotypes having distinctly different mean performance for various characters were reported into different clusters.Rice