A Trait Pyramiding Approach for Development of Non-Parametric Stability Models in Chrysanthemum (Chrysanthemum Morifolium) Crop Varietal Release

Abstract

Plant breeding forms a vital part of horticulture, contributing significantly to the creation of new varieties with desirable traits. Diverse breeding methodologies have been adopted to achieve improvements in yield, biotic stress resistance, nutritional attributes, and adaptability to varying environments. In this pursuit, stability models are developed to release a promising line as a variety at the end of the evaluation trials. However, regular approach results in various stable line for various traits, making difficult for a holistic recommendation. Thus, through trait pyramiding concept, non-parametric stability models are developed to identify stable line(s) across all traits. This concept is demonstrated using various yield attributing traits of 15 Chrysanthemum lines evaluated at ICAR-Indian Institute of Horticultural Research, Bengaluru during 2023 to 2025. R-codes were developed for the analysis. Based on the Non-parametric stability models of Venugopalan indices, it was found that IIHR 4-8 and IIHR 2-16 are stable across all traits evaluated such as flower diameter (cm), number of flowers/plant, flower stalk length (cm), plant height (cm), plant spread (cm). These stable lines will be utilized effectively to release a variety holistically combining all desirable traits in crop hybridization trials, emphasizes the need to construct a non-parametric index for assessing the stability of a set of lines collectively based on various traits evaluated over multiple seasons or years in an experimental setup