Phenotypic diagnostics of Linum ussitatissimum L. germ plasma sample resistance to osmotic stress

Abstract

Due to the negative effect of climate change, the selection of stress-resistant genotypes becomes increasingly important for plant breeding and genetic research. This paper discusses the findings of laboratory testing of fiber flax accessions (G₁-G₂₀) from the collection fund of the Tyumen State University under osmotic stress. The research goal was to study the flax responses to three levels (E₁-E₃) of simulated stress factor on seed germination and the formation of morphometric parameters of sprouts. Using the combined analysis method according to the AMMI-biplot model, reliable (p < 0.05*, p < 0.01**) differences between the accessions (G₁-G₂₀) and environmental conditions (E₁-E₃) were revealed. Using principal component analysis, the structural nature of the complex genotype-environment interaction (GxE) was determined according to which the greatest contribution to its structure was made by the first IPCA₁ (51.3-42.8%) and the second IPCA₂ (34.6-22.8%) accounting for 85.9-65.6% of the total variability of the test criteria. The ambiguous nature of the phenotype-response reactions in the flax germplasm samples was expressed in decrease of the germination index (GP) by 5.7-2.8%, root length (RW) - 3.8-1.9%, shoot length (SW) - 8.3-4.7%, root wet weight (FRW) - 4.1-2.4%, shoot wet weight (FSW) - 6.1-2.9% with increased stress factor compared to the normal background (E₀) without revealing the stimulating effect of the environment. According to the component analysis (IPCA), valuable genotypes were selected in the E₁ medium (n = 10), E₂ medium (n = 6), and E₃ medium (n = 4). Based on the index method (SI, TOL), promising accessions of fiber flax G₂, G₇, G₈, G₁₃ were selected being of interest for further selective breeding work.