Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead t...Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon rice.Multi-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the yield prediction compared with previous methods.Thus,in this study,we explored the performance of combination of agronomic practice information(API)and single-phase,multi-spectral features[vegetation indices(VIs)and texture(Tex)features]in predicting ratoon rice yield,and developed a new UAV-based method to retrieve yield formation process by using multi-temporal features which were effective in improving yield forecasting accuracy of ratoon rice.The results showed that the integrated use of VIs,Tex and API(VIs&Tex+API)improved the accuracy of yield prediction than single-phase UAV imagery-based feature,with the panicle initiation stage being the best period for yield prediction(R^(2) as 0.732,RMSE as 0.406,RRMSE as 0.101).More importantly,compared with previous multi-temporal UAV-based methods,our proposed multi-temporal method(multi-temporal model VIs&Tex:R^(2) as 0.795,RMSE as 0.298,RRMSE as 0.072)can increase R^(2) by 0.020-0.111 and decrease RMSE by 0.020-0.080 in crop yield forecasting.This study provides an effective method for accurate pre-harvest yield prediction of ratoon rice in precision agriculture,which is of great significance to take timely means for ensuring ratoon rice production and food security.展开更多
Nitrogen is a key element to control the growth and yield of crops. Fertilizer urea nitrogen (N) 60,45, and 30 kg/hm2 was applied at three different stages, midtillering, panicle initiation, and flowering, of the grow...Nitrogen is a key element to control the growth and yield of crops. Fertilizer urea nitrogen (N) 60,45, and 30 kg/hm2 was applied at three different stages, midtillering, panicle initiation, and flowering, of the growth and development of rice plants, respectively. At both midtillering and panicle initiation, the total activity of glutamine synthetase (GS) in rice roots and leaves was incrased remarkably as a result of a large amount of ammonia absorbed by roots. Native-PAGE and activity staining showed that the increase of total activity in rice roots and leaves was due to the synthesis of GSrb in roots and GS2 in leaves and that the activity of GSra in roots and GS1 in leaves remained constant. The results showed that the assimilation of external nitrogen was carried out by GSrb but not GSra in rice roots and that the activitry of GS2 was induced also by the external nitrogen, and that GSrb played main role in meeting the needs of the rapid tillering for nitrogen. At flowering, the activity of GS in rice roots and leaves did not change almost after topdressing. These rssults suggest that the change of GS activity in rice roots may use as a measure of the utilization efficiency of the fertilizer.展开更多
Unmanned aerial vehicle(UAV)has offered a promising platform for rice direct seeding that can substantially reduce labor input in the crop establishment process.However,the insufficient payload capacity of UAV-based s...Unmanned aerial vehicle(UAV)has offered a promising platform for rice direct seeding that can substantially reduce labor input in the crop establishment process.However,the insufficient payload capacity of UAV-based seeders is currently limiting its intensive and large-scale use for rice direct seeding.This study indicated a large variation in seed weight across varieties,ranging from 15.0 to 36.5 mg and 14.0 to 31.3 mg for inbred and hybrid varieties,respectively,with average seed weights of 25.3 mg for inbred and 24.7 mg for hybrid varieties.Seed weights of 160 out of 4106 inbred varieties and 17 out of 311 hybrid varieties ranged from 15.0 to 20.0 mg.展开更多
基金supported by the Key Research and Development Program of Heilongjiang,China(Grant No.2022ZX01A25)Cooperative Funding between Huazhong Agricultural University and Shenzhen Institute of Agricultural Genomics(Grant No.SZYJY2022014)+2 种基金Fundamental Research Funds for the Central Universities,Beijing,China(Grant Nos.2662022JC006 and 2662022ZHYJ002)National Natural Science Foundation of China(Grant No.32101819)Huazhong Agriculture University Research Startup Fund,China(Grant Nos.11041810340 and 11041810341).
文摘Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon rice.Multi-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the yield prediction compared with previous methods.Thus,in this study,we explored the performance of combination of agronomic practice information(API)and single-phase,multi-spectral features[vegetation indices(VIs)and texture(Tex)features]in predicting ratoon rice yield,and developed a new UAV-based method to retrieve yield formation process by using multi-temporal features which were effective in improving yield forecasting accuracy of ratoon rice.The results showed that the integrated use of VIs,Tex and API(VIs&Tex+API)improved the accuracy of yield prediction than single-phase UAV imagery-based feature,with the panicle initiation stage being the best period for yield prediction(R^(2) as 0.732,RMSE as 0.406,RRMSE as 0.101).More importantly,compared with previous multi-temporal UAV-based methods,our proposed multi-temporal method(multi-temporal model VIs&Tex:R^(2) as 0.795,RMSE as 0.298,RRMSE as 0.072)can increase R^(2) by 0.020-0.111 and decrease RMSE by 0.020-0.080 in crop yield forecasting.This study provides an effective method for accurate pre-harvest yield prediction of ratoon rice in precision agriculture,which is of great significance to take timely means for ensuring ratoon rice production and food security.
文摘Nitrogen is a key element to control the growth and yield of crops. Fertilizer urea nitrogen (N) 60,45, and 30 kg/hm2 was applied at three different stages, midtillering, panicle initiation, and flowering, of the growth and development of rice plants, respectively. At both midtillering and panicle initiation, the total activity of glutamine synthetase (GS) in rice roots and leaves was incrased remarkably as a result of a large amount of ammonia absorbed by roots. Native-PAGE and activity staining showed that the increase of total activity in rice roots and leaves was due to the synthesis of GSrb in roots and GS2 in leaves and that the activity of GSra in roots and GS1 in leaves remained constant. The results showed that the assimilation of external nitrogen was carried out by GSrb but not GSra in rice roots and that the activitry of GS2 was induced also by the external nitrogen, and that GSrb played main role in meeting the needs of the rapid tillering for nitrogen. At flowering, the activity of GS in rice roots and leaves did not change almost after topdressing. These rssults suggest that the change of GS activity in rice roots may use as a measure of the utilization efficiency of the fertilizer.
基金the National Natural Science Foundation of China(Grant Nos.32101819 and 31971845)the China Postdoctoral Science Foundation(Grant No.2021M691179)the earmarked fund for China Agriculture Research System(Grant No.CARS-01-20).
文摘Unmanned aerial vehicle(UAV)has offered a promising platform for rice direct seeding that can substantially reduce labor input in the crop establishment process.However,the insufficient payload capacity of UAV-based seeders is currently limiting its intensive and large-scale use for rice direct seeding.This study indicated a large variation in seed weight across varieties,ranging from 15.0 to 36.5 mg and 14.0 to 31.3 mg for inbred and hybrid varieties,respectively,with average seed weights of 25.3 mg for inbred and 24.7 mg for hybrid varieties.Seed weights of 160 out of 4106 inbred varieties and 17 out of 311 hybrid varieties ranged from 15.0 to 20.0 mg.
