对盐度胁迫的耐受性是细胞和整个植物水平的复杂现象,需要了解促进生理和生化过程以及参与性状的遗传控制。在这种情况下,本研究的目的是评估生理,生物化学,以及在盐水和对照环境下不同小麦基因型(包括面包小麦(BW)和合成六倍体(SHs))的遗传响应。实验在随机完全区组设计(RCBD)中进行两个阶乘排列,基因型作为一个因素,治疗作为另一个因素。生理性状显著下降(叶绿素,光合作用,气孔导度,蒸腾作用,和细胞膜稳定性)由于盐胁迫而在所有基因型中都观察到;然而,与四种SH基因型相比,BW基因型的下降幅度更高。此外,生化特性包括酶[超氧化物歧化酶,过氧化氢酶,和过氧化物酶(POD)]活性,脯氨酸,和甘氨酸甜菜碱(GB)说明随着相应基因(TaCAT1,TaSOD,TaPRX2A,TaP5CS,和TaBADH-A1)由于与BW相比,SHs中的盐胁迫。相应地,高度过度表达的基因,与盐胁迫下的BW基因型相比,TaHKT1;4,TaNHX1和TaAKT1导致SH中Na/K的显着下降。此外,相关分析,主成分分析(PCA),和热图分析进一步证实,生理生化性状的关联和表达随盐度胁迫和基因型类型的不同而显著变化。总的来说,生理,生物化学,遗传评估证明SHs是通过正确的育种程序将盐度耐受性转移到其他优良BW品种的最有用的种群。
The tolerance to salinity stress is an intricate phenomenon at cellular and whole plant level that requires the knowledge of contributing physiological and biochemical processes and the genetic control of participating traits. In this context, present study was conducted with objective to evaluate the physiological, biochemical, and genetic responses of different wheat genotypes including bread wheat (BW) and synthetic hexaploids (SHs) under saline and control environment. The experiment was conducted in two factorial arrangement in randomized complete block design (RCBD), with genotypes as one factor and treatments as another factor. A significant decline in physiological traits (chlorophyll, photosynthesis, stomatal conductance,
transpiration, and cell membrane stability) was observed in all genotypes due to salt stress; however, this decline was higher in BW genotypes as compared to four SH genotypes. In addition, the biochemical traits including enzymes [superoxide dismutase, catalase, and peroxidase (POD)] activity, proline, and glycine betaine (GB) illustrated significant increase along with increase in the expression of corresponding genes (TaCAT1, TaSOD, TaPRX2A, TaP5CS, and TaBADH-A1) due to salt stress in SHs as compared to BW. Correspondingly, highly overexpressed genes, TaHKT1;4, TaNHX1, and TaAKT1 caused a significant decline in Na+/K+ in SH as compared to BW genotypes under salt stress. Moreover, correlation analysis, principal component analysis (PCA), and heatmap analysis have further confirmed that the association and expression of physiological and biochemical traits varied significantly with salinity stress and type of genotype. Overall, the physiological, biochemical, and genetic evaluation proved SHs as the most useful stock for transferring salinity tolerance to other superior BW cultivars via the right breeding program.