Effect Of Foliar Application Of Spermidine After Anthesis On The Quality Of Wheat

With economic development,population increase,and quality of life improved,consumers have also pursued a higher level of wheat quality.The grain quality of winter wheat is not only affected by genetic factors and ecological environment,but also controlled by cultivation measures such as moisture and soil nitrogen fertilizer.Polyamines,as an important type of growth regulator,widely affect the biological activity of plants and significantly affect the formation of crop quality.Based on this,this study selected the wheat varieties Xinong538 and Lankaoaizao 8,and sprayed different concentrations of exogenous spermidine during the grain filling stage after anthesis to determine the content of protein,amylose,amylopectin,and starch in the grain.Grain characteristics,starch viscosity characteristics,dough mixing characteristics,dough processing characteristics and other quality indicators,mainly to study the effects of post-flowering spermidine foliar application on wheat yield and grain quality,and analyze the effects of foliar application spermidine on wheat grain quality,The main conclusions are as follows:1.Foliar application of spermidine after anthesis increased wheat yield.The 1000-grain weight of the tested varieties Xinong 538 and Lankaoaizao 8 increased significantly under the treatment of spermidine,which in turn increased the wheat yield.Under the spraying treatment of spermidine with a concentration of 0.75 mmol L^-1,the grain weight and yield of wheat showed the best performance.2.Different types of proteins have inconsistent responses to spermidine.Large-spike cultivars may require a higher concentration to increase the crude protein content of wheat,while the total protein of Xinong 538,a small-spike cultivar,has a better improvement effect under the treatment of low concentration of spermidine.In terms of protein components,the gluten and gliadin of wheat Xinong 538 were significantly increased under spermidine treatment,while the other two proteins changed little;foliar application with different concentrations of spermidine significantly increased Lankaoaizao 8 the content of the four protein components,especially gliadin;the higher the spray concentration of spermidine,the higher the gliadin content and the higher the gluten content.Different concentrations of foliar spermidine sprays will reduce the wheat grain alcohol ratio to different degrees.Foliar application of spermidine is not conducive to the formation of soluble protein of Xinong 538.For Lankaoaizao 8,the higher the concentration of spermidine spraying,the better the formation of soluble protein.As far as wheat protein is concerned,the spraying concentration of exogenous spermidine of 0.25-0.75 mmol L^-1 is more suitable for small-spike variety Xinong 538,while the suitable spraying concentration of exogenous spermidine for large-spike variety Lankaoaizao 8 is 0.75-1 mmol L^-1.3.Foliar application of spermidine after anthesis significantly affected the content of amylose and amylopectin and the distribution of starch grains in wheat.The amylose of Xinong 538 was significantly reduced under the treatment of spermidine spraying.The amylose of Lankaoaizao 8 increased with the increase of spraying concentration,and the amylopectin decreased significantly under different concentration treatments.The amylose/amylose ratio of Xinong 538 decreased significantly after spraying spermidine on the leaves after anthesis,while the value of Lankaoaizao 8 increased significantly.Foliar application of spermidine after anthesis significantly reduced the number of wheat A-type starch grains,but increased the proportion of B-type starch granules,and the number of A/B-type starch granules decreased in the two varieties;wheat A/B under different treatments The volume of type starch granules changes.The sphericity of starch granules changed significantly under the treatment of spermidine.The amylose content of Xinong 538 under the spraying treatment of exogenous spermidine was lower than that of the control.The foliar applicaton of spermidine after anthesis was more conducive to the formation of starch in large-spike variety Lankaoaizao 8.The more suitable spraying concentration was 0.75mmol L^-1.4.Foliar application of spermidine after anthesis significantly affects wheat starch viscosity characteristics,dough mixing characteristics and processing quality.The Final viscosity,Trough viscosity,Setback,bulk density,Sds content and Gluten value of Lankaoaizao 8 increased significantly under foliar application of spermidine,while the sedimentation value and gluten value of Xinong 538 decreased significantly.The dough characteristics of different spike-type wheat The treatment of spermidine is inconsistent.Spraying spermidine improves the strength of the dough,and it is more resistant to kneading than the control CK dough under constant shearing and high temperature.Under foliar application of spermidine,the water absorption rate of wheat Xinong 538 increased significantly,while the water absorption rate of Lankaoaizao 8 decreased significantly;the change of bulk density was just opposite to the water absorption rate.In terms of dough mixing characteristics and processing characteristics,the optimal concentration of exogenous spermidine foliar spray for spikelet-type variety Xinong 538 is 0.25-0.75 mmol L^-1,and the optimal concentration for large-spike-type wheat Lankaoaizao 8 is 0.75-1mmol L^-1.Based on this experimental study,the quality indicators of large-spike wheat variety Lankaoaizao 8 under the spraying concentration of exogenous spermidine of 0.75-1 mmol L^-1 have undergone major changes,and important indicators such as protein,starch,and kneading characteristics have improved significantly.It can be used as a reference concentration for spraying spermidine in the field.However,spikelet-type variety Xinong538is more sensitive to changes in spermidine concentration,and the appropriate field spray concentration is recommended to be 0.25-0.75 mmol L^-1.