Remote sensing technology has long been used to detect and map crop diseases.Airborne and satellite imagery acquired during growing seasons can be used not only for early detection and within-season management of some...Remote sensing technology has long been used to detect and map crop diseases.Airborne and satellite imagery acquired during growing seasons can be used not only for early detection and within-season management of some crop diseases,but also for the control of recurring diseases in future seasons.With variable rate technology in precision agriculture,site-specific fungicide application can be made to infested areas if the disease is stable,although traditional uniform application is more appropriate for diseases that can spread rapidly across the field.This article provides a brief overview of remote sensing and precision agriculture technologies that have been used for crop disease detection and management.Specifically,the article illustrates how airborne and satellite imagery and variable rate technology have been used for detecting and mapping cotton root rot,a destructive soilborne fungal disease,in cotton fields and how site-specific fungicide application has been implemented using prescription maps derived from the imagery for effective control of the disease.The overview and methodologies presented in this article should provide researchers,extension personnel,growers,crop consultants,and farm equipment and chemical dealers with practical guidelines for remote sensing detection and effective management of some crop diseases.展开更多
Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,...Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,uneven fertilizer-spreading uniformity is becoming a key factor restricting the application of centrifugal fertilizer spreaders.Accordingly,the particle application characteristics and variation laws for centrifugal VRF spreaders with multi-pass overlapped spreading needs to be urgently explored,in order to improve their distribution uniformity and working accuracy.In this study,the working performance of a self-developed centrifugal VRF spreader,based on real-time growth information of rice and wheat,was investigated and tested through the test methods of using the collection trays prescribed in ISO 5690 and ASAE S341.2.The coefficient of variation(CV)was calculated by weighing the fertilizer mass in standard pans,in order to evaluate the distribution uniformity of spreading patterns.The results showed that the effective application widths were 21.05,22.58 and 23.67 m for application rates of 225,300 and 375 kg/ha,respectively.The actual fertilizer application rates of multi-pass overlapped spreading were generally higher than the target rates,as well as the particle distribution CVs within the effective spreading widths were 11.51,9.25 and 11.28%for the respective target rates.Field test results for multi-pass overlapped spreading showed that the average difference between the actual and target application was 4.54%,as well as the average particle distribution CV within the operating width was 11.94%,which met the operation requirements of particle transverse distribution for centrifugal fertilizer spreaders.The results and findings of this study provide a theoretical reference for technical innovation and development of centrifugal VRF spreaders and are of great practical and social significance for accelerating their application in implementing precision agriculture.展开更多
It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of ...It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of soil analysis for NPK determination using the digital soil test kit.NPK determination procedure with a digital soil test kit was undefined for oil palm.Furthermore,the digital soil test kit determines the passage of light through an opaque medium of soil solution with a specified reagent.Therefore,environmental light may interfere leading to wrong results of NPK measurement.Likewise,this equipment was non-incorporable with the controller of any VRT fertilizer applicator.In this research,these issues were addressed and the NPK measurement procedure was defined for oil palm plantation by modifying the‘soil to water’ratio in sample soil solution with an optimum environmental light range of 18-23 W/m^(2).‘Soil to water’ratios were found for nitrogen,phosphorus and potassium as 0.31 to 5.00,1.00 to 5.00 and 4.50 to 5.00,respectively to fit the requirement of NPK for oil palm in the prescribed range of the equipment.Validation study of modified digital soil test kit showed that 91.7%N,89.6%P and 93.8%K results of modified digital soil test kit were matched with analytical laboratory method.Thus,the reliability of NPK results using digital soil test kit was enhanced,making the kit incorporable with the controller of variable rate fertilizer applicator through remote monitoring based data acquisition system.The outcome of this research can be used in the development of an IoT network data fusion for dynamic assessment of the NPK variation in the soil and nutrient management in oil palm plantations.展开更多
文摘Remote sensing technology has long been used to detect and map crop diseases.Airborne and satellite imagery acquired during growing seasons can be used not only for early detection and within-season management of some crop diseases,but also for the control of recurring diseases in future seasons.With variable rate technology in precision agriculture,site-specific fungicide application can be made to infested areas if the disease is stable,although traditional uniform application is more appropriate for diseases that can spread rapidly across the field.This article provides a brief overview of remote sensing and precision agriculture technologies that have been used for crop disease detection and management.Specifically,the article illustrates how airborne and satellite imagery and variable rate technology have been used for detecting and mapping cotton root rot,a destructive soilborne fungal disease,in cotton fields and how site-specific fungicide application has been implemented using prescription maps derived from the imagery for effective control of the disease.The overview and methodologies presented in this article should provide researchers,extension personnel,growers,crop consultants,and farm equipment and chemical dealers with practical guidelines for remote sensing detection and effective management of some crop diseases.
基金the Jiangsu Agricultural Science and Technology Innovation Fund(Grant No.CX(23)3029)the Natural Science Foundation of Jiangsu Province(Grant No.BK20210410)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.YDZX2024033)the National Key Project of Research and Development Program(Grant No.2023YFD200100102,2023YFD200100204).
文摘Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,uneven fertilizer-spreading uniformity is becoming a key factor restricting the application of centrifugal fertilizer spreaders.Accordingly,the particle application characteristics and variation laws for centrifugal VRF spreaders with multi-pass overlapped spreading needs to be urgently explored,in order to improve their distribution uniformity and working accuracy.In this study,the working performance of a self-developed centrifugal VRF spreader,based on real-time growth information of rice and wheat,was investigated and tested through the test methods of using the collection trays prescribed in ISO 5690 and ASAE S341.2.The coefficient of variation(CV)was calculated by weighing the fertilizer mass in standard pans,in order to evaluate the distribution uniformity of spreading patterns.The results showed that the effective application widths were 21.05,22.58 and 23.67 m for application rates of 225,300 and 375 kg/ha,respectively.The actual fertilizer application rates of multi-pass overlapped spreading were generally higher than the target rates,as well as the particle distribution CVs within the effective spreading widths were 11.51,9.25 and 11.28%for the respective target rates.Field test results for multi-pass overlapped spreading showed that the average difference between the actual and target application was 4.54%,as well as the average particle distribution CV within the operating width was 11.94%,which met the operation requirements of particle transverse distribution for centrifugal fertilizer spreaders.The results and findings of this study provide a theoretical reference for technical innovation and development of centrifugal VRF spreaders and are of great practical and social significance for accelerating their application in implementing precision agriculture.
基金This research was supported by Universiti Putra Malaysia in coordination of United Melaka Bhd.(UMB).
文摘It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of soil analysis for NPK determination using the digital soil test kit.NPK determination procedure with a digital soil test kit was undefined for oil palm.Furthermore,the digital soil test kit determines the passage of light through an opaque medium of soil solution with a specified reagent.Therefore,environmental light may interfere leading to wrong results of NPK measurement.Likewise,this equipment was non-incorporable with the controller of any VRT fertilizer applicator.In this research,these issues were addressed and the NPK measurement procedure was defined for oil palm plantation by modifying the‘soil to water’ratio in sample soil solution with an optimum environmental light range of 18-23 W/m^(2).‘Soil to water’ratios were found for nitrogen,phosphorus and potassium as 0.31 to 5.00,1.00 to 5.00 and 4.50 to 5.00,respectively to fit the requirement of NPK for oil palm in the prescribed range of the equipment.Validation study of modified digital soil test kit showed that 91.7%N,89.6%P and 93.8%K results of modified digital soil test kit were matched with analytical laboratory method.Thus,the reliability of NPK results using digital soil test kit was enhanced,making the kit incorporable with the controller of variable rate fertilizer applicator through remote monitoring based data acquisition system.The outcome of this research can be used in the development of an IoT network data fusion for dynamic assessment of the NPK variation in the soil and nutrient management in oil palm plantations.
