不同追氮时期对饲用燕麦生理特性和产量品质的影响OA

This study aimed to investigate the effects of nitrogen(N)fertilizer application timing on the yield and quality of forage oats,specifically using two varieties,i.e.,'Mengyan 1'and'Mengte'.A total nitrogen application rate of 100 kg·hm-2 was used,with 30%allocated as base fertilizer and 70%as top dressing.Four distinct nitrogen top-dressing periods were established,includ-ing tillering fertilizer(N1),jointing fertilizer(N2),booting fertilizer(N3),and heading fertilizer(N4).The control treatment(N0)involved no nitrogen application through out the growth period.The study examined nitrogen accumulation in various above-ground organs of oats,the growth status at the heading and maturity stages,yield composition,and grain quality.The results indicat-ed that different nitrogen application timings significantly affected oat yield and quality.Compared to the control treatment,the N3 treatment resulted in a 30%significantly increase in hay yield and a 65%increase in grain yield.Additionally,the crude protein content of grains from'Mengyan 1'increased by 12%,while the fat content decreased by 10%for'Mengyan 1'and by 7%for'Mengte'.Pearson correlation analysis and random forest relative importance rankings revealed that the primary factors influencing hay yield included the number of grains per panicle,stem dry matter at the heading stage,leaf dry matter at the heading stage,nitro-gen content in leaves at the heading stage,number of panicles,nitrogen content in stems at the heading stage.For the grain yield,key factors included the number of grains per panicle,stem dry matter at maturity,stem dry matter at the heading stage,panicle dry matter at maturity,leaf area.Significant indicators for crude protein content in grains were nitrate reductase activity in flag leaves and leaf area.Nitrogen content in panicles at the heading stage significantly influenced the fat content in grains.In conclusion,applying nitrogen fertilizer during the booting stage could lead to a reduction in the number of panicles per unit area,while simultaneously in-creasing leaf area and nitrogen content.This practice effectively enhanced the dry matter accumulation and increased the number of grains per panicle,ultimately resulting in improved oat yield.Furthermore,nitrogen fertilization could increase leaf area and enhance nitrate reductase activity in the flag leaf during the heading stage,contributing to an elevated crude protein content in the grains.