盐胁迫对不同品种小麦幼苗生长发育的影响OA

[Objective]To explore the differences in physiological responses among different wheat cultivars under salt stress.[Method]Four wheat cultivars,namely Shannong 56,Shannong 40,Jimai 22,and Shannong 27,were used as experimental materials.Three salt concentra-tion treatments were set up:0.0%(control),0.2%,and 0.4%.The growth parameters,fluorescence characteristics,and changes in physi-ological metabolism of seedlings of each cultivar under salt stress were analyzed.[Result]Salt stress inhibited the growth of wheat seedlings,with significant inter-cultivar differences in stress tolerance.Under the low-salt treatment(0.2%NaCl):For Shannong 56,root length and soluble sugar content decreased by 9.51%and 21.83%relative to the control,respectively;meanwhile,the non-photochemical quenching co-efficient(q N)and peroxidase(POD)activity increased by 6.82%and 21.87%,respectively.In Shannong 40,fresh weight per plant and chlorophyll content were reduced by 13.70%and 20.19%compared with the control,while its malondialdehyde(MDA)content showed the smallest increase(2.92%)among the four cultivars.Jimai 22 exhibited reductions in plant height,secondary root number,and actual photo-chemical efficiency Y(PSⅡ)by 16.28%,9.40%,and 10.44%,respectively;in contrast,MDA content and superoxide dismutase(SOD)activity increased by 31.48%and 17.78%.Shannong 27 showed overall stable performance across all indicators and strong resistance to oxi-dative stress.Under the high-salt treatment(0.4%NaCl):Shannong 56 had a 3.41%reduction in secondary root number relative to the con-trol.Shannong 40 displayed the highest reduction in non-regulated energy dissipation Y(NO)(8.33%)among the four cultivars.Jimai 22 was the most severely inhibited overall:plant height,fresh weight per plant,dry weight per plant,chlorophyll content,and Y(PSⅡ)all de-creased significantly compared with the control,and its MDA content increased by 44.98%.Shannong 27 showed increases in Y(NO)and photochemical quenching coefficient(qP)by 0.57%and 9.28%,respectively,indicating strong tolerance to oxidative stress.[Conclusion]Significant inter-cultivar variations in salt tolerance were observed among the tested wheat cultivars:Shannong 27 was classified as salt-toler-ant,Shannong 40 as moderately salt-tolerant,Shannong 56 as salt-sensitive,and Jimai 22 as highly salt-sensitive.