Effects of salt stress on morpho-biological traits of cotton in laboratory condition
Аннотация
Approximately 830 million hectares of agricultural land are exploited for human consumption, with 6 % being severely saline. If salinity levels continue to rise, 50 % of existing crops might be under salinity stress by 2050. Cotton growth suffers when soil salt levels rise year after year. Cotton has moderate resilience to salt stress, with tolerance levels of up to 7.7 dS/m-1 (decisiemens per meter). Abiotic stress-tolerant cotton lines and contemporary molecular breeding technologies are critical for creating high-quality, high-yielding novel cotton varieties under abiotic stress conditions. In this study, a recombinant inbred line population was used as the experimental material. Recombinant inbred line (RIL) population obtained by crossing Namangan-77 and KK-1795 cotton genotypes were phenotypically evaluated under control, 100 mM NaCl and 200 mM NaCl salt stress conditions. Various morpho-biological traits were evaluated, including total plant length (TPL), total shoot length (TShL), total root length (TRL), fresh plant weight (FPW), fresh shoot weight (FShW), fresh root weight (FRW), dry shoot weight (DShW), dry root weight (DRW), leaf number (LN) and chlorophyll content in normal condition (ChlC). Correlation analysis of morphological traits revealed highly significant links among the 10 cotton traits grown in laboratory conditions. The TPL showed a significant and strong correlation with FPW and significantly positive correlations were identified between DShW and LN. Also, TRL exhibited a significant positive correlation with FRW and DRW under salt stress conditions. The analysis revealed that salt-tolerant RILs identified were RIL-05, RIL-09, RIL-11, RIL-17, RIL-45, RIL-48, RIL-53, RIL-54, RIL-56, RIL-58, RIL-60, RIL-65, RIL-75 and RIL-85. These results suggest that selected RILs genotypes will be valuable genetic materials for developing salt-stress-resistant cotton varieties.