干旱胁迫下烯效唑对糜子幼苗光合荧光特性的调控效应

Effects of Uniconazole on Photosynthetic Fluorescence Characteristics of Broomcorn Millet Seedlings under Drought Stress

为探究烯效唑(S3307)对干旱胁迫下糜子幼苗光合荧光特性的调控效应,本研究以榆糜3号为材料,采用水培试验,通过20%PEG模拟干旱条件,设置4个处理,即喷施清水+0%PEG(CK1)、喷施烯效唑+0%PEG(CK2)、喷施清水+20%PEG(T1)、喷施烯效唑+20%PEG(T2),研究烯效唑对干旱胁迫下糜子幼苗的农艺性状、干物质分配和叶片光合荧光参数的影响。结果表明:与CK1相比,干旱胁迫后(T1)显著降低了糜子幼苗的株高和叶面积,叶干重占比也不断下降,同时降低了糜子幼苗叶绿素荧光光合参数;与T1相比,干旱胁迫后喷施烯效唑(T2)增加了糜子幼苗株高、叶面积、总根长、根总表面积、根体积,分别升高了26.7%、86.29%、54.69%、56.50%、13.33%,同时提高了茎、叶干重的占比;提高糜子幼苗叶片叶绿素含量,第6天增长到25.97%,Fv/Fm、ФPSⅡ分别增加了65.00%、74.72%。因此,干旱条件下喷施烯效唑有利于提高糜子根系形态特征,改善糜子幼苗叶片的光合荧光特性,从而增强糜子植株的抗旱能力。

To investigate the regulatory effect of uniconazole(S3307)on photosynthetic fluorescence characteristics of broomcorn millet seedlings under drought stress,we took Yuli No.3 as the material and conducted an hydroponic experiment to simulate drought conditions using 20%PEG,and designed four treatments accordingly.We studied the effects of four treatments on agronomic traits,dry matter accumulation and photosynthetic fluorescence parameters of leaves under drought stress,the four treatments included uniconazole+0%PEG(CK1),uniconazole+0%PEG(CK2),uniconazole+20%PEG(T1),and uniconazole+20%PEG(T2).The results showed that compared with CK1,drought stress(T1)significantly reduced the plant height and leaf area of broomcorn millet seedlings,and decreased the leaf dry weight ratio and the chlorophyll fluorescence photosynthetic parameters of the seedlings.However,when uniconazole(T2)was applied under drought stress,the plant height,leaf area,total root length,total root surface area and root volume of broomcorn millet seedlings increased by 26.7%,86.29%,54.69%,56.50%,and 13.33%,respectively,compared to T1.Furthermore,the proportion of stem and leaf dry weight increased.The diameter of PSⅡincreased by 65.00%,and Fv/Fm and leaf chlorophyll content increased by 74.72%and 41.86%,respectively,on the sixth day.Therefore,under drought conditions,the application of uniconazole can improve the root morphological characteristics of glutinous millet,enhance the photosynthetic fluorescence characteristics of seedling leaves,and improve the drought resistance of broomcorn millet plants.