Effects Of Reduced Application Of Chemical Fertilizers And Pesticides On Growth,Yield And Grain Quality Of Winter Wheat In Rice Stubble

In order to clarify the effects of reduced chemical fertilizers and pesticides on the growth,yield and grain quality of winter wheat in rice stubble in the hilly wheat region of northeast Sichuan,field experiments were carried out with Chuanmai 104,Xikemai 8 and Xikemai 18 as experimental materials.Under the condition of returning rice stubble to the field,the experiment set 3 chemical fertilizer reduction treatments,namely T₁（reduction of chemical fertilizer application by 10%）,T₂（reduction of chemical fertilizer application by17%）,and T₃（reduction of chemical fertilizer application by 24%）;One,namely W₁（pesticide reduction 25%+stimulant）,W₂（pesticide reduction 30%+stimulant）,W₃（pesticide reduction 35%+stimulant）,and set a control.The wheat growth,yield benefit and grain quality under different fertilizer treatments were analyzed.The specific results are as follows:1.Wheat growth difference:The growth of the wheat plant height by reducing the chemical fertilizer by 17%is better than other treatments,which is conducive to the formation of plant height at the mature stage.The reduced application of chemical fertilizers will increase the number of wheat ears,the thickness of the stems,and the dry matter quality will gradually decrease;reducing the application of 25%and 30%of pesticides will promote the formation of the final plant height of wheat.The reduced application of various pesticides combined with stimulating health had little effect on the number of wheat ears.The stem thickness showed a downward trend after 30%reduction of pesticides combined with stimulation treatment,and no effect under 25%reduction of pesticides combined with stimulation treatment.The lower the pesticide dosage,the greater the dry matter quality of the plant at the tillering stage,and the dry matter growth of each treatment in the later period gradually recovered,and it had no effect on the final dry matter accumulation of wheat.2.Wheat yield traits:the number of degraded spikelets of various varieties of wheat increased with the increase in the amount of chemical fertilizers reduced.A 10%reduction in chemical fertilizer will increase the ear length and number of spikelets in Chuanmai 104and Xikemai 8.The thousand-grain weight and effective ear number of Xikemai 8 increased by 17%reduction of chemical fertilizer.There was no significant effect on the effective ears,thousand-grain weight,and number of seeds of Chuanmai 104 within 24%of reduced chemical fertilizer application.The reduced application of chemical fertilizers will significantly reduce the 18 ear length,number of spikelets,and number of real grains of Westcourt wheat,but has no significant effect on its effective ear and 1000-grain weight;in the three treatments with reduced pesticide application and strong application,wheat ear length,number of spikelets,The number of degenerated spikelets showed an increasing trend.The 35%reduction of pesticide application and the combined application range of Jijian had no significant effect on the number of real seeds of Chuanmai 104 and Xikemai No.8,while the number of real seeds of Xikemai 18 decreased.The 30%reduction of pesticide application and the combined application of Jijian had no effect on the thousand-seed weight of each variety.3.Correlation analysis of yield and yield traits:Chuanmai 104 had no significant effect on yield when chemical fertilizers were reduced by 17%or pesticides were reduced by 30%.The yield of Xikemai 8 increased under reduced fertilizer application.Reduced application of 17%or reduced application of pesticides by 30%combined with stimulation is the most beneficial to yield efficiency,but it is not conducive to the production of Xicoma 18 under this experimental treatment.Correlation analysis showed that yield was significantly positively correlated with ear length,number of spikelets,number of effective ears,and number of grains,and significantly negatively correlated with the number of degraded spikelets.Under the treatment of reduced fertilizer application,the yield was also significantly positively correlated with the number of ears.4.Analysis of Wheat Kernel Quality:17%reduction in chemical fertilizers had larger wheat grains and better grain uniformity.Under the three fertilizer reduction treatments,protein and wet gluten showed a downward trend with the increase in the reduced fertilizer application rate.A 24%reduction in chemical fertilizer application would significantly reduce the protein content of Sikemai 18.In the treatment of reduced fertilizer application,Chuanmai 104 and Xikemai 8 showed an increase in amylose and a decrease in amylopectin as the amount of chemical fertilizer decreased,which had no effect on the amylose of Xikemai 18,and its amylopectin had an increasing trend.;A 30%reduction in pesticide application combined with Jijian wheat has larger grains and high grain uniformity.There is no significant effect on wet gluten and protein content under the treatment of reduced application of pesticides and stimulant application.Within the 35%reduction of pesticide application,the amylose content of all kinds of Jijian varieties showed an upward trend.Chuanmai 104 and Xikemai 8 showed an upward trend with the decrease of pesticide concentration.For Xikemai 18 amylopectin The starch content has little effect.5.Yield benefit:Chuanmai 104 has little change in the economic benefits under the17%reduction in chemical fertilizer application,but the 30%reduction in pesticide application and the combined application of aggressive health have improved the economic benefits.Reduced application of chemical fertilizers and pesticides can increase the economic benefits of Xikemai No.8,and it is best to reduce the application of chemical fertilizers by 17%,reduce the application of pesticides by 30%,and the combined application of vigorous health.This experimental treatment will reduce the economic benefits of Sikemai 18,and the efficiency of resource input will be low.The results of this year showed that the reduction of chemical fertilizer application of Chuanmai 104 by 17%had little effect on the characteristics and benefits,and the reduction of pesticide application by 30%and the combination of aggressive application would increase yield and benefit.Xikemai 8 performed the best under the conditions of 17%reduction in chemical fertilizer application or 30%reduction in pesticide application combined with stimulation.In this experimental study,it is not conducive to the production of Xikemi 18.Therefore,in actual production,it is necessary to reduce the application of appropriate fertilizers according to the characteristics of different varieties in order to obtain better benefits.The results of this study can provide a reference for the reduction of fertilizers and medicines for winter wheat in Sichuan rice crops.