Overuse of irrigation water to ensure the crop yield of maize plants has caused serious water shortage problems in the middle reach of Heihe River, China. Thus, further research on the physiological characteristics, i...Overuse of irrigation water to ensure the crop yield of maize plants has caused serious water shortage problems in the middle reach of Heihe River, China. Thus, further research on the physiological characteristics, i.e., photosynthetic rate and leaf transpiration rate, are urgently needed to develop an efficient irrigation management system. In this paper, we selected two common soil textures (sandy loam, sand) and three one-time irrigation volumes (60 mm, 20 mm, 0 mm) in order to analyze the impact of soil conditions on the physiological characteristics of maize plants. Physiological and meteorological factors, soil water content and plant growing parameters were synchronously monitored on Jun. 30, Jul. 25 and Aug. 27 of 2012. The results indicate that sandy loam is better than sand for the growth of maize plants and single irrigation may provide limited influence on the physiological characteristics. Thus, increasing irrigation times and decreasing one-time volume is suggested for an efficient irrigation system.展开更多
Plant height can be used for assessing plant vigor and predicting biomass and yield. Manual measurement of plant height is time-consuming and labor-intensive. We describe a method for measuring maize plant height usin...Plant height can be used for assessing plant vigor and predicting biomass and yield. Manual measurement of plant height is time-consuming and labor-intensive. We describe a method for measuring maize plant height using an RGB-D camera that captures a color image and depth information of plants under field conditions. The color image was first processed to locate its central area using the S component in HSV color space and the Density-Based Spatial Clustering of Applications with Noise algorithm. Testing showed that the central areas of plants could be accurately located. The point cloud data were then clustered and the plant was extracted based on the located central area. The point cloud data were further processed to generate skeletons, whose end points were detected and used to extract the highest points of the central leaves. Finally, the height differences between the ground and the highest points of the central leaves were calculated to determine plant heights. The coefficients of determination for plant heights manually measured and estimated by the proposed approach were all greater than 0.95. The method can effectively extract the plant from overlapping leaves and estimate its plant height. The proposed method may facilitate maize height measurement and monitoring under field conditions.展开更多
Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conduc...Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conducive to causing a higher rate of seedling damage.In order to realize maize(Zea mays L.)intra-row weeding,a maize intra-row weeding mechanism was designed in this study.The mechanism can detect maize seedlings by infrared beam tube,then a sliding-cutting bevel tool moves spirally amid maize seedlings,so as to eradicate intra-row weeds.A field experiment was conducted under the following experimental conditions:the bevel tool rotation speed was 800-1400 r/min,the mechanism forward speed was 4-7 km/h,and the bevel tool depth was 2-14 cm,the experimental results illustrated that the mechanism’s average weeding rate and seedling damage rate were 95.8%and 0.6%,respectively.The variance analysis showed that the primary and secondary factors that affecting the weeding rate and seedling damage rate were the same,which were bevel tool rotation speed,mechanism forward speed,bevel tool depth in soil in a descending order according to the significances.The result of the field experiment may provide a reference for intra-row weeding device design.展开更多
Low accuracy planting uniformity affects yield.Seed meter type and forward speed typically interfere with the planting uniformity accuracy of motor-driven seeding systems.Two types of maize precision planters equipped...Low accuracy planting uniformity affects yield.Seed meter type and forward speed typically interfere with the planting uniformity accuracy of motor-driven seeding systems.Two types of maize precision planters equipped with motor-driven planting systems are investigated in this study to ascertain the rule of planting uniformity in both simulated and field speeds.The simulated speed increases from 5 to 12 km/h at a 1 km/h interval in a laboratory environment.The test results show that the quality of feed index(QTFI)of the two planters decreased by 16.79%and 9.88%.This is primarily attributed to the increase in the miss index(MISS)by 11.62%and 9.70%,respectively.The field speed was set to four levels from 5 to 12 km/h in a field environment.The plant spacing scatter distribution results were analyzed,and the results of the two planters indicated that the average positive difference of the two planters linearly increased with the forward speed,and the negative difference of the two planters did not exhibit a linear correlation.The number of positive moving average points was 2.49 times greater than that of the negative moving average points of the finger pick-up maize precision planter,and 4.49 times in the air-suction maize precision planter.The results indicated that the increase of the positive difference of plant spacing is the major effect factor in the field planting uniformity of the two motor-driven maize precision planters.In addition,the plant spacing corresponded to the distribution frequency of the two planters in field was close to the target seed spacing of 25 cm with a max coefficient of variation(CV)of 21.55%and 20.66%,respectively,and those plant spacing values corresponded to max distribution frequency of the two planters at the four level field speeds were(24.69±0.63)cm and(25.63±0.32)cm,respectively.However,the multiples index(MUL)changed randomly affected by the increasing speed.The research results provide a direction for the optimization design of motor-driven maize precision planters.展开更多
基金supported by the China Postdoctoral Science Foundation (Grant No. 2015M572622)the National Natural Science Foundation of China (Grant No. 41501044)
文摘Overuse of irrigation water to ensure the crop yield of maize plants has caused serious water shortage problems in the middle reach of Heihe River, China. Thus, further research on the physiological characteristics, i.e., photosynthetic rate and leaf transpiration rate, are urgently needed to develop an efficient irrigation management system. In this paper, we selected two common soil textures (sandy loam, sand) and three one-time irrigation volumes (60 mm, 20 mm, 0 mm) in order to analyze the impact of soil conditions on the physiological characteristics of maize plants. Physiological and meteorological factors, soil water content and plant growing parameters were synchronously monitored on Jun. 30, Jul. 25 and Aug. 27 of 2012. The results indicate that sandy loam is better than sand for the growth of maize plants and single irrigation may provide limited influence on the physiological characteristics. Thus, increasing irrigation times and decreasing one-time volume is suggested for an efficient irrigation system.
基金supported by the Key Project of Intergovernmental Collaboration for Science and Technology Innovation under the National Key R&D Plan (2019YFE0103800)CAU Special Fund to Build World-class University (in disciplines) and Guide Distinctive Development (2021AC006)。
文摘Plant height can be used for assessing plant vigor and predicting biomass and yield. Manual measurement of plant height is time-consuming and labor-intensive. We describe a method for measuring maize plant height using an RGB-D camera that captures a color image and depth information of plants under field conditions. The color image was first processed to locate its central area using the S component in HSV color space and the Density-Based Spatial Clustering of Applications with Noise algorithm. Testing showed that the central areas of plants could be accurately located. The point cloud data were then clustered and the plant was extracted based on the located central area. The point cloud data were further processed to generate skeletons, whose end points were detected and used to extract the highest points of the central leaves. Finally, the height differences between the ground and the highest points of the central leaves were calculated to determine plant heights. The coefficients of determination for plant heights manually measured and estimated by the proposed approach were all greater than 0.95. The method can effectively extract the plant from overlapping leaves and estimate its plant height. The proposed method may facilitate maize height measurement and monitoring under field conditions.
基金supported by the National Natural Science Foundation of China(Grant No.31901408).
文摘Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conducive to causing a higher rate of seedling damage.In order to realize maize(Zea mays L.)intra-row weeding,a maize intra-row weeding mechanism was designed in this study.The mechanism can detect maize seedlings by infrared beam tube,then a sliding-cutting bevel tool moves spirally amid maize seedlings,so as to eradicate intra-row weeds.A field experiment was conducted under the following experimental conditions:the bevel tool rotation speed was 800-1400 r/min,the mechanism forward speed was 4-7 km/h,and the bevel tool depth was 2-14 cm,the experimental results illustrated that the mechanism’s average weeding rate and seedling damage rate were 95.8%and 0.6%,respectively.The variance analysis showed that the primary and secondary factors that affecting the weeding rate and seedling damage rate were the same,which were bevel tool rotation speed,mechanism forward speed,bevel tool depth in soil in a descending order according to the significances.The result of the field experiment may provide a reference for intra-row weeding device design.
基金financially supported by the Beijing Rural Revitalization Science and Technology Project(20220614-02)National Key Research and Development Plan Project(2019YFE0125200)Hebei Province key research and development program(21327205D).
文摘Low accuracy planting uniformity affects yield.Seed meter type and forward speed typically interfere with the planting uniformity accuracy of motor-driven seeding systems.Two types of maize precision planters equipped with motor-driven planting systems are investigated in this study to ascertain the rule of planting uniformity in both simulated and field speeds.The simulated speed increases from 5 to 12 km/h at a 1 km/h interval in a laboratory environment.The test results show that the quality of feed index(QTFI)of the two planters decreased by 16.79%and 9.88%.This is primarily attributed to the increase in the miss index(MISS)by 11.62%and 9.70%,respectively.The field speed was set to four levels from 5 to 12 km/h in a field environment.The plant spacing scatter distribution results were analyzed,and the results of the two planters indicated that the average positive difference of the two planters linearly increased with the forward speed,and the negative difference of the two planters did not exhibit a linear correlation.The number of positive moving average points was 2.49 times greater than that of the negative moving average points of the finger pick-up maize precision planter,and 4.49 times in the air-suction maize precision planter.The results indicated that the increase of the positive difference of plant spacing is the major effect factor in the field planting uniformity of the two motor-driven maize precision planters.In addition,the plant spacing corresponded to the distribution frequency of the two planters in field was close to the target seed spacing of 25 cm with a max coefficient of variation(CV)of 21.55%and 20.66%,respectively,and those plant spacing values corresponded to max distribution frequency of the two planters at the four level field speeds were(24.69±0.63)cm and(25.63±0.32)cm,respectively.However,the multiples index(MUL)changed randomly affected by the increasing speed.The research results provide a direction for the optimization design of motor-driven maize precision planters.