Evaluation of opium poppy genotypes for tolerance to drought, salinity, and low temperatures during the germination stage

Seed germination is a crucial stage in determining the ability of seedlings to emerge and establish. However, it is mainly influenced by genetic factors and unfavorable environmental conditions such as drought, salinity, and low temperatures. In this study, the germination ability of three opium poppy cultivars (Çelikoğlu, Hüseyinbey, and Seyitgazi) and local genotypes (population 4, 6, and 7) was evaluated under various drought stresses (0, -2, -4, and -6 bar induced by PEG 6000) and NaCl salinities (0, 5, 10, 15, and 20 dS/m). Germination percentage, mean germination time, germination index, and germination stress tolerance index were used to assess the response of poppy genotypes to low temperature stress (5, 10, 15, and 20°C). Emergence performance was also tested under salt and low-temperatures (20°C and 15°C). The results showed that increasing salinity led to a decrease in germination percentage and an increase in mean germination time of poppy seeds. Notably, Hüseyinbey had higher and faster germination than the other genotypes. Under drought conditions, no germination was recorded at -6 bar, but Hüseyinbey had the highest germination percentage, germination index, and stress tolerance index at -2 and -4 bar. Pop 4 showed superior germination characteristics at low temperatures. The stress tolerance index and germination index may be useful criteria for selecting plants that can withstand low temperatures. It was determined that poppy genotypes responded differently to abiotic stresses, with Hüseyinbey and Seyitgazi showing resilience to salinity and drought. Moreover, local populations may serve as genetic resources for cold tolerance, given the superior performance of Pop 4 at low temperatures. • Environmental factors negatively impact opium poppy seed germination performance. • Genotypic heterogeneity was detected for germination performance of poppy genotypes. • Local poppy genotype (Pop. 4) should be a valuable resource for low-temperature stress. • Hüseyinbey and Seyitgazi should be preferred for better seedling establishment under drought and salinity.