Effects of one-time base application with reduced amount of controlled-re-lease nitrogen fertilizer and density increase on yield,quality and econom-ic benefits of mechanized-transplanting japonica rice
This study aimed to investigate the effects of one-time base application with reduced amount of con-trolled-release nitrogen fertilizer and increased density on the yield,quality and economic benefits of mechanized-transplanting japonica rice,thereby clarifying the optimal combination of nitrogen fertilizer and planting density.In the study,a japonica rice cultivar-Nanjing 5718 was selected as the test material.And nine combinations with three con-trolled-release periods(60 days,80 days and 100 days)of controlled-release fertilizer and three planting densities(six seed-lings per hole,eight seedlings per hole and ten seedlings per hole)were set up under 225 kg/hm2 pure nitrogen,while the conventional split fertilization treatment with 300 kg/hm2 pure nitrogen and a planting density of four seedlings per hole was installed as the control(CK).The differences in yields and their formation characteristics,rice quality,and economic bene-fits were investigated.The results showed that the yield of 80-6 treatment was the highest in all nitrogen reduction treatments in 2021 and 2022,which was significantly higher than that of other nitrogen reduction treatments,and the yield was signifi-cantly reduced by 4.77％-5.17％compared with CK.From jointing stage to heading stage,the dry matter accumulation of 80-6 treatment was generally increased compared with other nitrogen reduction treatments.In terms of rice quality,the chalky grain rate and chalkiness degree of each nitrogen reduction treatment were lower than those of CK,and the nutritional quality(protein content)was significantly reduced,but the appearance quality and taste quality were significantly improved.In terms of economic benefits,the 80-6 treatment achieved the highest economic benefits under the one-time basal application of con-trolled-release fertilizer in 2021 and 2022,and the economic benefits increased by 3.60％-5.28％compared with CK.There-fore,80-6 treatment can improve rice quality and obtain higher economic benefits under the premise of reducing nitrogen and ensuring stable yield.It can be used as a combination of nitrogen fertilizer and planting density for one-time nitrogen reduction fertilization treatment with high yield,high quality and high efficiency of mechanically transplanted japonica rice.
japonica ricecontrolled-release fertilizernitrogen reduction and density increaseyieldqualityeconomic benefits
万方数据
维普
