statistics measure genetic divergence among populations or genotypes. By grouping genotypes into distinct clusters, breeders can deliberately cross genetically distant parents to maximize heterosis (hybrid vigor) and generate transgressive segregants. Path Coefficient Analysis
Ideal for controlling field gradients in one direction.
Arises from the interaction of alleles at the same locus (intra-allelic interaction).
The observable association between two traits.
Dr. Jawahar R. Sharma earned his Ph.D. from Kanpur University while working at the . With over 15 years of experience at IARI and later at CIMAP (Lucknow) , he became an authority on crop improvement and the genetic upgradation of medicinal and aromatic plants. Genetic Diversity Analysis: Statistical Approaches Arises from the interaction of alleles at the
): Non-fixable variance, highly utilized in hybrid breeding. Interaction effects between different gene loci. 3. Heritability and Genetic Advance Broad-Sense Heritability ( hb2h sub b squared
For complex breeding goals where multiple traits must be improved simultaneously, univariate statistics fall short. The text introduces advanced multivariate techniques: Mahalanobis’ D2cap D squared
While Jawahar R. Sharma’s book focuses on traditional phenotypic and biometrical data, its principles remain highly relevant in the era of digital agriculture and molecular breeding.
Plant breeding shifts away from simple visual selection when dealing with quantitative traits like crop yield, drought tolerance, or nutritional quality. These traits are controlled by multiple genes (polygenes) and are heavily influenced by the environment. Jawahar R
A large portion of the book is dedicated to understanding how parents pass traits to their offspring. Sharma provides detailed mathematical formulations for various mating designs used to estimate additive, dominance, and epistatic genetic variances:
A diallel involves crossing a set of parents in all possible combinations.
Students and researchers searching for the digital PDF version of this textbook can optimize their study approach by focusing on its practical structure:
Associated with additive gene action; helps identify the best parents. helps identify the best parents.
Identifies varieties with stable performance across locations.
A variety that performs exceptionally well in one location might fail in another. Sharma outlines the biometrical tools used to evaluate environmental stability:
The book provides step-by-step statistical procedures for executing and analyzing major mating designs: