Assessing Genetic Diversity in Bread Wheat (Triticum aestivum L.) using D2 Statistical Analysis

Background: Genetic diversity is one of the potent components used to develop improved cultivars with a broad genetic base and wider adaptability. Genetic diversity between two parents of diverse origin generally displays greater heterosis and yields transgressive segregants. Therefore, knowledge of genetic diversity is the prerequisite for the genetic improvement of crop plants including wheat. D2 statistical analysis is one of the potent biometrical techniques used for the assessment of genetic diversity. Methods: The essence of the current experiment involved 40 providential bread wheat lines that were arranged and laid down in a randomized block design (RBD) with three replications at the experimental research farm of Suresh Gyan Vihar University, Jagatpura, Jaipur, during the rabi crop season (2020-21). The bread wheat lines of the same geographical range were assessed to determine the genetic diversity using D2 statistical analysis and heritability estimate in apropos to ten quantitative/qualitative characters. Result: Based on D2 analysis, the 40 promising wheat strains were lined up into ten different clusters to estimate the average distance at intra and inter-cluster levels. The uttermost intra-cluster distance was recorded in cluster X, whereas, the appreciative inter-cluster distance pertained among cluster-VI and cluster-X pursued by cluster-IX and cluster-X. Entrenched to the mean or average performance, most of the bread wheat lines were spotted to disclose appreciable distinctions concerning to their cluster means. It was perceived that the maximum percent contribution towards total divergence was exhibited by grain yield plant-1, followed by spike length, effective tiller plant-1, 1000 grain weight and plant height. Moreover, the number of effective tillers plant-1, spike length, harvest index ,1000 grain weight, number of grains spike-1 and protein content were quite substantial since these traits exhibit high heritability estimate together with high genetic advance as percent of mean.