施氮量与移栽密度对小粒型杂交水稻产量形成的影响OA北大核心CSTPCD

[Objective]To elucidate the yield formation characteristics of small-seed hybrid rice.[Method]Zhuoliangyou 0985(small-seed hybrid rice variety)and Fengliangyou 4(control variety)were utilized as materials for a field experiment at varying nitrogen application rates(0,N0;180 kg/hm2,N1;210 kg/hm2,N2)and densities(26.7 cm×20.0 cm,D1;20.0 cm×20.0 cm,D2;20.0 cm×16.7 cm,D3)[Result]The leaf area index(LAI)and leaf SPAD values of the two varieties increased with nitrogen application rate,with no significant difference between N1 and N2,but significantly higher than N0 treatment.The dry matter output rate of stems and sheaths decreased with rising nitrogen application,while leaf matter output rate followed the opposite trend.Grain yield of both varieties increased with increasing nitrogen application,with no significant difference between N1 and N2.Among different density treatments,D2 generally yielded higher results.Under N0 treatment,Zhuoliangyou 0985 had significantly higher yield than the control variety,while under nitrogen application conditions,both varieties had equivalent yields.[Conclusion]The yield formation characteristics of Zhuoliangyou 0985 include smaller leaf area,more grains per panicle,larger sink-source ratio,noticeable photosynthetic advantages during mid to late grain filling stages,higher post-flowering substance accumulation and transport rate of stem and leaf substances,higher harvest index,and increased yield under nitrogen-deficient conditions.In the context of this experiment,N1D2(180 kg/hm2,20cm×20cm)emerged as the optimal treatment for Zhuoliangyou 0985.