光及激素协同提升水稻幼苗水分利用效率的机制OA
Improving water use efficiency and salt-drought tolerance in rice seedlings via gibberellic acid seed soaking and light supplementation
[目的]探究赤霉素浸种与远红光-蓝光补光双因素协同处理对盐旱胁迫下水稻幼苗水分利用效率与抗逆性的影响.[方法]以籼型常规稻"荆占1 号"种子为材料,设置双因素试验,试验因素为农艺处理方式和胁迫条件,其中农艺处理方式水平为蒸馏水浸种+无补光处理(WN)与 150 mg/L 赤霉素浸种+夜间远红光-蓝光补光协同(GL),胁迫条件为 1个无胁迫条件(CK)及 8个胁迫条件,包括2 个干旱胁迫(T1:10%PEG-6000,T2:15%PEG-6000)、2个盐分胁迫(T3:0.075 mol/L NaCl,T4:0.15 mol/L NaCl)及4个盐旱复合胁迫(T5:0.075 mol/L NaCl+10%PEG-6000,T6:0.15 mol/L NaCl+10%PEG-6000,T7:0.075 mol/L NaCl+15%PEG-6000,T8:0.15 mol/L NaCl+15%PEG-6000),共计 18个处理,研究赤霉素浸种+夜间远红光-蓝光补光协同处理对不同胁迫条件下干物质积累、根冠比、光合参数、水分利用效率及抗氧化-氧化损伤指标的影响.[结果]GL 处理缓解了盐分、干旱及其复合胁迫对幼苗生长的抑制作用,其水稻幼苗的地上部与地下部干质量较 CKGL 处理提升 3.22%～12.90%与 17.19%～40.63%,根冠比提高14.56%～54.08%;GL 处理水稻幼苗的净光合速率与叶片水分利用效率表现出相对优势,较相同胁迫程度下 WN 处理分别提高 0.81%～41.81%与 2.19%～71.47%,但仍低于 CKGL 处理.GL 处理提高了水稻幼苗的抗氧化酶量、超氧化歧化酶与过氧化物酶量,同时降低了过氧化氢酶、丙二醛与过氧化氢量;相关分析表明,GL 处理中水分利用效率与光合速率的相关性最高(R2=0.53),与过氧化物酶相关性最低(R2=0.071),水分利用效率与各指标的相关系数表现为光合速率＞丙二醛=过氧化氢酶＞超氧化物歧化酶＞过氧化氢＞根冠比＞过氧化物酶.[结论]赤霉素浸种与远红光-蓝光补光协同处理通过强化碳同化而非单纯提升抗氧化酶活性,优化水稻幼苗水分利用效率与盐旱耐受性.
[Objective]Rice seedlings are susceptible to salt and drought stresses.Herein,we investigate the efficacy of seed soaking with gibberellic acid combined with red-blue light supplementation on water use efficiency and stress resistance of rice seedlings under salt and drought stress.[Method]Rice variety'Jingzhan No.1'was used in the experiment.The agronomic treatments included seed soaking in distilled water without supplemental lighting(WN)and seed soaking in a solution with 150 mg/L gibberellic acid combined with nighttime far-red-blue light supplementation(GL).There were two drought treatments with PEG-6000 concentrations in the medium set at 10%(T1)and 15%(T2)respectively,two salinity treatments with NaCl concentrations of 0.075 mol/L(T3)and 0.15 mol/L(T4)respectively,and four combined salt-drought treatments formed by combining T1-T2 with T3-T4.During the experiment,we measured dry matter accumulation,root-to-shoot ratio,photosynthetic traits,water use efficiency,and antioxidant and oxidative stress indicators.[Result]The GL treatment alleviated the inhibitory effects of salt and drought,both individually and in combination,on seedling growth.When other conditions were the same,GL increased aboveground and belowground dry weights by 3.22%-12.90%and 17.19%-40.63%,respectively,and root-to-shoot ratio by 14.56%-54.08%compared with the WN treatment.GL also improved net photosynthetic rate and leaf water use efficiency by 0.81%-41.81%and 2.19%-71.47%,respectively.GL enhanced the activities of antioxidant enzymes(superoxide dismutase and peroxidase),while reducing catalase activity,malondialdehyde content,and hydrogen peroxide levels.Correlation analysis showed that water use efficiency was most strongly correlated with photosynthetic rate(R2=0.53)and least correlated with peroxidase activity(R2=0.071).The factors affecting water use efficiency were ranked as follows:photosynthetic rate＞malondialdehyde ≈ catalase＞superoxide dismutase＞hydrogen peroxide＞root-to-shoot ratio＞peroxidase.[Conclusion]Seed soaking in gibberellic acid solution combined with far-red-blue light supplementation improves water use efficiency and enhances salt-drought tolerance of rice seedlings primarily due to the improved carbon assimilation rather than solely because of the enhanced antioxidant enzyme activity.
林诗淼;朱梅;刘硕硕;孙丹晨
安徽农业大学 工学院,合肥 230036安徽农业大学 工学院,合肥 230036安徽农业大学 工学院,合肥 230036安徽农业大学 工学院,合肥 230036
农业科技
水稻盐旱复合胁迫赤霉素浸种远红光-蓝光补光水分利用效率
ricecombined salt-drought stressgibberellic acid seed soakingfar-red-blue light supplementationwater use efficiency
《灌溉排水学报》 2026 (6)
10-18,9
安徽省高等学校科学研究重点项目(2022AH050905)安徽省自然科学基金项目(2308085US06)
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