稻虾共作模式下氮肥减施对稻米品质的影响OA

To explore the optimal nitrogen reduction ratio in the rice-crayfish co-culture system,a field experiment was conducted us-ing conventional indica rice Ezhong 6 and hybrid indica rice Longliangyou 534 as test varieties,and five nitrogen application treat-ments were set up,including conventional nitrogen application rate(N4,pure nitrogen 180.0 kg/hm2),10%nitrogen reduction(N3,pure nitrogen 162.0 kg/hm2),20%nitrogen reduction(N2,pure nitrogen 144.0 kg/hm2),30%nitrogen reduction(N1,pure nitrogen 126.0 kg/hm2),and no nitrogen application(N0).The differences of rice quality between the rice-crayfish co-culture system and the rice monoculture system were investigated,and the changes of protein,amylose and their key enzyme activities were analyzed.The re-sults showed that under the rice-crayfish co-culture system,as the nitrogen fertilizer reduction ratio increased,the brown rice rate,milled rice rate,head rice rate,chalky grain rate,chalkiness and the total protein content of both varieties decreased,while the amy-lose content,gel consistency and taste value increased.No significant differences in processing quality or protein content were ob-served between the N3 and N4 treatments,whereas the N3 treatment demonstrated superior appearance,cooking,and eating quality.Compared with the rice monoculture system,the rice-crayfish co-culture system generally produced higher-quality rice.It could be seen that the synergistic goal of"nitrogen reduction-quality improvement-efficiency"could be achieved when the proportion of nitro-gen fertilizer reduction was 10%under the rice-crayfish co-culture system.