Chlorophyll a fluorescence activity and genetic heritability of morphological attributes among mid-early and late-duration indica rice genotypes of Odisha

Selection of suitable rice genotype is very important for higher production of rice in current climate changing environment. Genetic diversity of mid-early (IR87439, Ciherang Sub1, Lalat) and late-duration (IR85086, Savitri Sub1, Mahanadi) varieties of rice (Oryza sativa L.) were analyzed with yield attributing traits along with photosystem II activity. 100-grain weight was significantly high in Ciherang Sub1 (2.77 g) with low grain number per panicle and showed moderately high fertile grain number in IR85086 (2.66 g). Significantly high harvest Index was recorded in Savitri Sub1 with highest plot yield of 83.45 q ha−1 which was 1.15 fold more than Swarna. A significant positive correlation (r = 0.81) was noticed between plant height and leaf area. Plant height, panicle length, flag leaf area had significant positive correlation with 100-grain weight. Significant alteration of chlorophyll a florescent transient leading to photosynthetic efficiency was recorded in the studied genotypes. O-J-I-P analysis revealed significant relative variable fluorescence intensity at ‘J’ transient point among the mid-early and late-duration varieties. Total performance index on absorption basis was found significantly high in mid-early varieties as compared to late-duration varieties. Phylogenetically mid-early and late-duration varieties were grouped separately on the basis of yield attributes. The identified genetically distinct genotype Ciherang Sub1 could be selected for breeding partner with varieties having high grain number and weight to improve grain number per panicle through conventional breeding program. Such study might be useful in assessment of genetic diversity and photosynthetic efficiency for future rice breeding program. © 2022, The Author(s) under exclusive licence to Society for Plant Research.