Effects Of Foliar Spraying Zinc Fertilizer And Melatonin After Anthesis On Filling Characteristics And Grain Quality Of Wheat Cultivar Xinong 538

Wheat is one of the important food crops,and high demand for the yield and quality on wheat in China.Although there are many high-yield wheat varieties in China,the high-quality special varieties cannot meet the market demand.Therefore,shorten of high-quality wheat cultivar is still a more prominent problem at present.During the whole process of wheat growth and development,the filling period is an important period which has a big impact on wheat quality and yield.During the filling stage,the reasonable application of foliar fertilizer has an important impact on wheat yield and processing quality.The trace element zinc has an important biological function on the plant growth and development.As a component of chlorophyll and multiple enzymes and a catalyst,zinc participates in the metabolic processes of photosynthetic carbon assimilation and nitrogen assimilation in plants.Melatonin,due to its strong antioxidant properties,can quickly remove active oxygen free radicals in plants and stabilize the redox state of cells.However,there are few studies on the effects of spraying zinc fertilizer and melatonin at the anthesis stage on the filling and quality of strong gluten wheat in Shaanxi Province.In this experiment,a high-quality strong gluten wheat variety Xinong 538 was used as the test material,and zinc sulfate and melatonin were used as foliar spraying in the test field.Through determination of the dry weight of the grain,the malondialdehyde content of the flag leaf,the antioxidant enzyme activity of the flag leaf,the thousand-grain weight,the yield,and the grain quality and the flour quality after harvesting,we found that the application of zinc and melatonin had a big impact not just on filling characteristics and wheat filling characteristics but also grain quality and processing quality,which provides a theoretical basis for wheat quality breeding.The main results are as follows:(1)The thousand-grain weight of wheat grains treated by zinc or melatonin during the grain filling stage consistents with the basic law of growth curve,and the overall trend is an S-shaped upward trend.At 5-10 days after anthesis,the difference in thousand-grain weight was not obvious.At fifteen days after anthesis,the difference of thousand-grain weight between the treatments were increased.At twenty days after anthesis,the difference in the thousand-grain weight between the treatments reached the maximum.The increasing trend of the grouting rate treated with zinc was similar to the control during at early stage,then increased significantly at the late grouting period.In the middle grouting,the thousand-grain weight of the melatonin-treated grain was higher than that of the control,and it was close to the control at the later period of grain filling.The 1000-grain weight and yield of wheat grains treated with melatonin increased by 3.54% and 2.9% compared with the control,respectively.The effect of zinc sulfate treatment on the 1000-grain weight and yield of wheat was not significant.(2)Compared with the control,zinc treatment and melatonin treatment delayed the senescence of wheat leaves to a certain extent.There was no significant difference in the SPAD value of flag leaves between the zinc treatment and melatonin treatment at the early or late filling stages.The flag leaf SPAD value treated with zinc was significantly higher than that of the control at 10-25 days after anthesis,which was conducive to wheat photosynthesis,while the effect on the SPAD value of flag leaves treated with melatonin is less than that of zinc treatment;zinc treatment has a greater effect on the MDA content of wheat flag leaves,on the contrary,melatonin has a less effect on the MDA content of flag leaves;compared with the control,both of the zinc treatment and melatonin treatment can improve the flag leaf SOD activity.(3)Both zinc treatment and melatonin treatment can have certain effects on wheat grain quality and flour quality.The zinc sulfate treatment increased the starch content by 2.60%,the crude protein content by 0.78%,the wet gluten content by 3.37%,the sedimentation value by 7.04%,the precipitation value by 12.43%,and the water absorption by 2.05% The resistance of the dough to elongation has also increased by 16.1%.The melatonin-treated grain hardness increased by 7.25%,grain starch content increased by 4.45%,grain crude protein content increased by 7.03%,wet gluten content increased by 9.48%,sedimentation value increased by 12.14%,drop value increased The resistance to elongation of the dough has increased by 19.28%.