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Fifty wheat genotypes were evaluated at the seedling stage of growth, for genetic variation in cellular thermotolerance by cell membrane thermostability (CMS) and Triphenyl tetrazolium choride (TTC) assays. A subset of eight genotypes was also evaluated at the anthesis stage using the same assays. Large and significant differences existed among wheat genotypes for TTC and CMS at the seedling and anthesis stages. Average thermotolerance declined from seedling to anthesis stage. Thermotolerance was well-correlated between growth stages among the eight genotypes for both CMS (r=0.95; p= 0.01) and TTC (r=0.92; p= 0.01). The correlation between TTC and CMS among the eight genotypes at seedling and anthesis stages was significant (r=0.95; p=0.01 and r=0.93; p= 0.01, respectively). The effect of heat stress on wheat genotypes selected on the basis of TTC and CMS thermotolerance ratings were evaluated. 1000-grain weight, grain filling duration (GFD) and grain filling rate (GFR) reduced under heat stress. The heat susceptibility index (S) revealed K-65 and Yangmai- 6 to be susceptible and NW-1014 and DBW-14 to be moderately tolerant to heat stress. GFR and 1000-grain weight were found to have highly significant positive correlation with CMS and TTC ratings at both seedling and anthesis stages. [ABSTRACT FROM AUTHOR]

Coix lacryma-jobi L. is a minor millet and an underutilized crop native to Asia that is of paramount importance in food and medicine. In India, the crop is mainly grown in the northeastern hill region for food, medicine, beverage, and fodder purposes. Genetic information on edible Job’s tears and wild relatives still needs improvement. Therefore, the study focused on characterizing 65 accessions of Job’s tears, including landraces and wild types collected from the northeastern hill region of India, using 20 morphological traits, three biochemical traits, and 16 SSR markers. Based on grain yield data, JTN11 and IC89392 were the most promising accessions. Biochemical analysis recorded IC417053, JTN3, and IC89393 as having the highest phenol content, antioxidant capacity, and flavonoid content, respectively. Principal component analysis showed that traits, namely, total phenol content, leaf length, spikelet/plant, brace root, and seed yield/plant, have significantly contributed to the diversity. In molecular characterization with SSR primers, 62 alleles were generated, with an average of 3.87 alleles per locus. The effective number of alleles detected varied from 1.17 (GBssrJT32) to 4.23 (GBssrJT198). Two alleles were found unique to wild accessions, underscoring the importance of preserving these varieties for future research and breeding. Based on the UPGMA dendrogram, IC416868, IC521338, IC417053, IC419466, IC540173, IC540281, IC89387, IC89393, and JTN3 were identified as diverse accessions. The high level of genetic diversity assessed in this study emphasizes the importance of the Indian NEH region for conserving Job’s tears germplasm. The observed pattern of genetic variations may be used to develop the breeding strategy in Job’s tears. [ABSTRACT FROM AUTHOR]