Morphological evaluation of green super rice for yield and yield-related traits under agro ecological conditions of Pakistan

Introduction of Green Super Rice (GSR) in Pakistan aims to develop high-yielding, quality and climate-resilient rice cultivars. In this regard, the morphological evaluation of 552 GSR lines for yield and related traits were studied using Alpha Lattice (LS) design with three replications. The phenotypic variability of GSR lines revealed significant mean sum of squares (p<0.01) for all the studied traits. On average, GSR lines showed maximum trait performances for days to flowering, days to ripening, days to maturity, tillers per plant, total biomass, straw yield per plant, grain yield per plant, and harvest index compared with the basmati and non-basmati rice. Relatively high heritability was estimated for days to flowering (97.8%), days to ripening (89%), days to maturity (98.5%), plant height (76.7%), and panicle length (78.8%), whereas, moderate heritability coupled with genetic advance was recorded for tillers per plant (41%), grain yield per plant (43%) and harvest index (53%). Correlation analysis revealed that grain yield per plant had strong and positive correlation with other yield-related traits; tillers per plant (r=0.51**), total biomass (r=0.48**), harvest index (r=0.32**) and straw yield per plant (r=0.28**). Moreover, principal components analysis (PCA) suggested that grain yield per plant, straw yield per plant and total biomass are critical traits that contributed significantly to the total variation in the GSR population. In conclusion, the GSR traits with superior heritability and yield performances are potentially valuable resources for developing high and stable rice cultivars in Pakistan.