Leveraging Quantitative Trait Variation for Targeted Selection of Accessions in a Validated Soybean [Glycine max (L.) Merrill] Mini Core Collection

Abstract

Soybean (Glycine max (L.) Merrill) is a seed legume of considerable economic importance. Characterising a mini core set and identifying trait-specific accessions can facilitate the effective use of extensive soybean germplasm collections in breeding programmes. The present investigation focused on selecting accessions with desirable individual and multiple traits from a representative soybean mini core collection comprising 75 germplasm accessions. The 75 accessions and three check varieties were characterised for seven quantitative traits using an alpha-lattice design at three locations, viz., the Zonal Agricultural Research Station, GKVK, Bengaluru, Channarayapatna and K. R. Pete, during Kharif 2023 and summer 2024. Best linear unbiased predictors (BLUPs) were estimated for all quantitative traits. The statistical analysis revealed significant differences among accessions for each trait, confirming substantial within-collection variability. Based on the [mean - 1 standard deviation] criterion, 10 early-flowering, eight short-statured and nine early-maturing accessions were selected. Based on the [mean + 2 standard deviations] criterion, six accessions with more secondary branches plant-1, eight with more pods plant-1, seven with greater hundred-seed weight and nine with higher seed yield plant-1 were identified. Eight accessions exhibited desirable performance for multiple traits and outperformed all three check varieties. These accessions may be preferentially used in crossing programmes to generate additional variability for developing varieties with traits preferred by farmers and end users.