Multi-environment screening of Linum germplasm collection for dissecting the potential of bud fly (Dasyneura lini Barnes) resistance and assembling a reference set for efficient utilization in genetic improvement

Abstract

Linseed or flaxseed (Linum usitatissimum L.) is one of the most ancient industrial crops domesticated for oil and natural fiber. Bud fly (Dasyneura lini Barnes) susceptibility is serious biotic stress affecting its production both quantitatively and qualitatively. It has economic significance particularly in Asian countries, causing substantial crop damage leading to significant yield penalty and deterioration of seed quality. In the present study, a large collection of 2598 linseed germplasm accessions from the Indian National Genebank were screened for bud fly infestation at two natural hot-spot locations in India. The maximum bud fly incidence across all four environments ranged from 47.93% to 90.47%. Based on average bud fly infestation over the environments, a reference set comprising 195 accessions including 46 resistant, 94 moderately resistant and 55 moderately susceptible/susceptible germplasm was developed. Further, a selected subset of 26 accessions having a common reaction against linseed bud fly at both locations was validated for resistance over multi-location-year environments (four environments over two years) through GGE biplot analysis. The GGE biplot revealed that two accessions, G22 (EC0993391) and G23 (IC0633096) were highly resistant (<10% bud fly damage) and most stable over the tested environments against bud fly infestation. Additionally, two accessions namely G15 (IC0498795) and G24 (EC0099001) were considered resistant as they showed consistent performance and low bud fly infestation in comparison to the resistant check (Neela). Moreover, these accessions had a great buffering capacity to perceive environmental signals for developing adaptive capacities in a wide range of environments. The identified germplasm accessions may serve as potential donors for accelerating the resistance breeding programme to impart a long-lasting, broad-spectrum resistance against linseed bud fly.