减氮配施微矿生物有机肥对花生根系构型、氮素积累和荚果产量的影响OA

This study was conducted through greenhouse pot and field experiments using peanut cultivar Weihua 25 as meterial.Taking no nitrogen(N)application(N0)and conventional N application of 120 kg·hm-2(N120)as controls,six treatments of formula fertilization were set under conditions of 25％N reduc-tion(90 kg·hm-2)and 50％N reduction(60 kg·hm-2),whose micromineral bio-organic fertilizer(MBF)application rates were 600,1 200 and 1 800 kg·hm-2,respectively,with the treatment codes as N90T600,N90T1200,N90T1800,N60T600,N60T1200,and N60T1800.The effects of reduced N application combined with MBF on peanut agronomic traits,root architecture,plant N accumulation,and pod yield were studied.The results showed that,in the greenhouse pot experiment,compared with N120 treatment,N90T1200 treatment significantly increased root length,root surface area,average root diameter and root volume at seedling stage by 19.49％,18.82％,12.25％and 14.77％,respectively;N accumulation in roots,stems and leaves increased by 40.77％,37.27％and 25.99％,respectively,and all reached significant levels;however,the improvement effects on rhizosphere soil ammonium-N content and urease activity were not significant.The field experiment further confirmed these findings.Compared with N120 treatment,N90T1200 treatment increased root length,root surface area,average root diameter and root volume at seedling stage by 25.03％,30.75％,27.83％and 36.34％,respectively,all reaching significant levels;N accumulation in roots,stems and leaves increased by 45.44％,32.39％and 31.92％,respectively,all also reaching significant levels;whereas rhizosphere soil am-monium-N content and urease activity showed no significant differences compared with N120 treatment.The re-sults of field experiment indicated that,compared with N120 treatment,N90T1200 treatment significantly in-creased peanut yield by 3.84％.In conclusion,this study suggested that the combined application of 25％re-duced N and 1 200 kg.hm-2 MBF(N90T1200)was the optimal fertilization scheme.The results could provide theo-retical supports and technical references for reducing chemical N fertilizer in sustainable peanut production.