The effect of the urease inhibitor,N-(n-butyl)thiophosphoric triamide(NBPT)at a range of application rates on rice production was examined in a field experiment at Jinxian County,Jiangxi Province,China.The normalized ...The effect of the urease inhibitor,N-(n-butyl)thiophosphoric triamide(NBPT)at a range of application rates on rice production was examined in a field experiment at Jinxian County,Jiangxi Province,China.The normalized difference vegetation index(NDVI)was measured at key growth stages in both early and late rice.The results showed that the grain yield increased significantly when urea was applied with NBPT,with the highest yield observed at 1.00%NBPT(wt/wt).NDVI differed with the growth stage of rice;it remained steady from the heading to the filling stage.Rice yield could be predicted from the NDVI taken at key rice growing stages,with R^(2) ranging from 0.34 to 0.69 in early rice and 0.49 to 0.70 in late rice.The validation test showed that RMSE(t·hm^(–2))values were 0.77 and 0.87 in early and late rice,respectively.Therefore,it was feasible to estimate rice yield for different amounts of urease inhibitor using NDVI.展开更多
基金supported by Special Fund for Agro-scientific Research in the Public Interest(201203030 and 201003016)the National Basic Research Program of China(2011CB100501-S06)Jiangxi Science and Technology Support plan(20141BBF60050).
文摘The effect of the urease inhibitor,N-(n-butyl)thiophosphoric triamide(NBPT)at a range of application rates on rice production was examined in a field experiment at Jinxian County,Jiangxi Province,China.The normalized difference vegetation index(NDVI)was measured at key growth stages in both early and late rice.The results showed that the grain yield increased significantly when urea was applied with NBPT,with the highest yield observed at 1.00%NBPT(wt/wt).NDVI differed with the growth stage of rice;it remained steady from the heading to the filling stage.Rice yield could be predicted from the NDVI taken at key rice growing stages,with R^(2) ranging from 0.34 to 0.69 in early rice and 0.49 to 0.70 in late rice.The validation test showed that RMSE(t·hm^(–2))values were 0.77 and 0.87 in early and late rice,respectively.Therefore,it was feasible to estimate rice yield for different amounts of urease inhibitor using NDVI.
