VARIATION IN CALLUS GROWTH AND IN VITRO REGENERATION AMONG CULTIVATED AND WILD WHEAT GENOTYPES UNDER INCREASING SALT STRESS CONDITIONS - Imen Klay; Leila Riahi; Hajer Slim-Amara; Abderrazak Daaloul (Journal of Animal and Plant Sciences, 2024)
Wheat is one of the most widely cultivated and important cereal crops globally, serving as a staple food for millions of people worldwide. However, wheat production is increasingly challenged by environmental stresses, particularly soil salinity. Developing salt-tolerant varieties is essential to enhance wheat yields in saline-prone regions, thereby ensuring food security and agricultural sustainability. This study evaluated the variations in salt stress tolerance among eight wheat genotypes, representing common wheat, durum wheat, and wild wheat, under in vitro culture conditions. Wheat calli, induced from immature embryos, were subjected to increasing NaCl concentrations in the culture media (0, 50, 100, 150 mM NaCl). Callogenesis rates, recorded after one month of in vitro culture during the induction phase, varied between 33% and 100%, with a significant effect of genotype. The Aegilops accessions showed the lowest callus weights at the end of the induction phase, while Vaga and Jenah Khotifa genotypes exhibited the highest biomass. Significant variations in callus growth and regeneration rates were observed among the studied genotypes under increasing salt stress levels. The obtained results indicated that the durum wheat variety Om Rabiaa, the common wheat variety Salambo, and the two wild accessions, especially MZ116, exhibited the highest salt stress tolerance potential among the studied wheat genotypes. Further investigations at transcriptomic and genomic levels are required to elucidate the molecular basis of their high tolerance to salt stress. These genotypes could be utilized to develop salt-tolerant cultivars, which is crucial in the context of global climate change, either through wheat breeding as donor parents or through genetic transformation strategies.
Keywords: journal article; Triticum; Aegilops; Salt stress; Callogenesis; Plant regeneration; Selection