栏目导航
- Finite Element Analysis of Rice Film Mulching Direct Seeding Machine Frame Based on ANSYS.
- 作者：暂无 年份期号： 2020-4 刊名：Forest Engineering 关键词：田间试验 水稻覆膜直播机 Rice mulching direct seeding machine static analysis 模态分析 modal analysis field trial 静力学分析
- 描述：In order to make the frame of the rice mulching direct seeding machine meet the load-bearing requirements of the mulching direct seeding work, avoid excessive deformation of the frame and affect the flatness of the cover, and to avoid resonance between the frame and the excitation source such as the engine, ANSYS is used to perform static analysis and modal analysis on the rice mulching direct seeding machine frame. Through static analysis of three material frames and comprehensive evaluation based on the analysis results, the frame of material Q235 is the best. In the modal analysis of the Q235 rack, the first six natural frequencies of the rack are obtained. The excitation frequency of the main excitation source is compared with the first six natural frequencies of the rack, and the comparison results show that the resonance phenomenon does not occur in the work of the rack. Finally, field tests verify that the designed frame can meet the requirements of the mulching direct seeding operation.
- Field Efficacy Test of Five Different Pesticides against Spodoptera exigua
- 作者：马丽颖 年份期号： 2020-9 刊名：Hans Journal of Agricultural Sciences 关键词：Field Efficacy Test 杀虫剂 Pesticide 甜菜夜蛾 田间药效试验 Spodoptera exigua
- 描述：In this experiment, five insecticides with different insecticidal mechanisms with high efficiency and low toxicity were selected for the field efficacy test of Spodoptera exigua on lettuce. The results showed that the five insecticides used in the experiment had certain control effect on Spodoptera exigua on lettuce. One day after the treatment, the control effect of the five pesticides reached the highest level, meaning that they all can kill pests quickly. Seven days after the treatment, three of them, 200 g/L chlorantraniliprole SC, 10.5% trifluoromethane EC and 30 billion PIB/g Spodoptera exigua Nucleopolyhedrosis virus WG, were still doing well with more than 89% control effect, and even had no adverse effect on lettuce.
- Fhb1基因改良‘周麦’品种赤霉病抗性研究
- 作者：李楠楠 年份期号： 2021-4 刊名：中国农学通报 关键词：田间鉴定 Fhb1基因 赤霉病 分子检测 小麦
- 描述：为加快‘周麦’品种赤霉病抗性改良,利用当地主栽‘周麦’品种(系)‘周麦22号’、‘周麦32号’、‘周11550’为母本,‘宁麦9号’‘、生选6号’‘、扬麦21号’等长江中下游地区抗赤霉病材料为父本配制一系列杂交组合,经过选择获得621份F3～F6后代材料。在田间选用来源于江苏和河南两地不同的赤霉病菌株,通过单花滴注法接种小穗进行赤霉病抗性鉴定,同时利用抗赤霉病主效基因Fhb1紧密连锁的诊断性标记His-InDel对后代材料进行分子检测。结果表明,江苏的赤霉病菌株接种后代材料田间鉴定为高抗和中抗的占总数的23.9%,而河南的赤霉病菌株感染后代材料田间鉴定为高抗和中抗占比为35.1%,说明后代材料的赤霉病抗性比感病亲本有明显的改良,而且材料对江苏的赤霉菌菌株的抗性比河南的赤霉菌菌株的抗性低。分子检测结果显示,携带Fhb1和不携带Fhb1的材料之间赤霉病抗性差异极显著。这表明利用Fhb1基因分子标记辅助选择技术可用于改良‘周麦’品种的赤霉病抗性。
- F.US-UFO型果园避障割草机试验研究
- 作者：沈启扬 年份期号： 2021-10 刊名：中国农机化学报 关键词：作业性能 果园避障割草机 田间生产性能 单边避障
- 描述：果树行间距一般比株间距大,可以利用割草机械直接进行除草作业,但是果树株间的杂草就不能很好的用割草机进行机械化作业清除。文章在江苏泰兴烨佳梨园、沛县聚英阁苹果园和睢宁官山楸树园对F.US-UFO型果园避障割草机开展田间试验,通过对收草质量、割幅、割茬高度、漏割率、避障损伤率、避障割草高度与行间高度最大差、最短避障距离的测定,测试机具作业性能;通过对使用可靠性系数、平均故障间隔时间、班次小时生产率、劳动生产率和单位面积耗油量的测定,测试其田间生产性能。试验结果表明:F.US-UFO型果园避障割草机既能完成行间割草作业也能完成株间割草作业。果园行间坡度越小,园间路面越平坦,果树株行距越大,割草机作业质量越高。割草机工作效率为0.49 hm2/h,单位面积耗油量为11.41 kg/hm2。
- Development of seeding rate detection system for precision and small amount sowing of wheat.
- 作者：Jiang Meng 年份期号： 2021-5 刊名：Transactions of the Chinese Society of Agricultural Engineering 关键词：agricultural machinery 田间试验 sensors seeding rate detection wheat field experiment 小麦 传感器 播种量监测 农业机械
- 描述：Seeding amount determines the distribution density of plants in the field, thereby posing a significant impact on the final yield of crops. Real-time detection of sowing amount is an inevitable trend in precise agriculture. However, the current technology is difficult to rapidly identify overlapping seeds for the total amount of wheat precision seeding. In this study, an accurate detection system with an interpolation sensor was developed to control the seeding amount in a wheat precision planter with a wide seedling strip. Infrared radiation LEDs were used as the sensitive elements, and the 24-bit ADS1256 as the high-precision sampling module. The sampling frequency of the system was determined to be 1×103 Hz. The process of seed falling was analyzed, where the seeds were sampled at least three times when the sensor was scanning over the detection areas. The sampling voltage of one seed, two seeds, and three seeds were obtained when the sensor passed through. Two sampling threshold divisions were set using the peak and the mean value, according to the sampling voltage. In the peak, 489 was the threshold value for 1 and 2 seeds while 616 for 2 and 3 seeds. In the mean, 277 was the threshold value for 1 and 2 seeds while 330 for 2 and 3 seeds. A detection system of precision seeding was realized to integrate with the interaction interface of touch screen personal-computer and drive control of a stepper motor. A field experiment of planter under static state was carried out to verify the detection accuracy of the system, the adaptability for different varieties of wheat and seeding frequency, and further to evaluate the two-threshold division. Three types of wheat were selected as the research objects, including Heng-Guan 35, Ji-Mai 22, and Cun-Mai 11. It was found that the peak detection was optimal, due to the low detection error and good adaptability to different wheat varieties. The peak detection was further revised, where the correction coefficient was 7.08%. A field experiment was also carried out to further verify the performance of the detection system under dynamic conditions. It was found that the absolute detection error of the system ranged from 1.12%~5.63%, and the mean absolute error was 3.12%, indicating a high detection accuracy for the high requirements under various sowing rates and operation speeds, as well as a high resistance to sunlight and dust interference. The finding can provide potential technical support for the design of seed tube sensor, and the rapid detection of seeding amount in the process of precision wheat sowing.
- Control efficacy of the combination of pyraclostrobin and epoxiconazole against wheat leaf rust and its safety evaluation on wheat plants.
- 作者：暂无 年份期号： 2023-1 刊名：Chinese Journal of Pesticide Science / Nongyaoxue Xuebao 关键词：pyraclostrobin 氟环唑 吡唑醚菌酯 复配 wheat leaf rust 小麦叶锈病 室内抑菌活性 田间防治效果 indoor inhibitory activity safety evaluation field control efficacy 安全性评价 epoxiconazole combination
- 描述：In order to screen out the chemical agents for controlling wheat leaf rust, pyraclostrobin, epoxiconazole and their combinations with different proportions were evaluated in this study, and the indoor control efficacies on wheat leaf rust as protective agents were determined by spray inoculation method, the safety on wheat and the field control efficacy of wheat leaf rust of the optimal compound ratio for indoor screening were investigated. The results showed that pyraclostrobin, epoxiconazole and their combination had strong inhibitory effect on the lesion expansion of wheat leaf rust. Among them, pyraclostrobin had stronger inhibitory activity, and its EC50 value was 0.01 μg/mL. The results of joint toxicity evaluation showed that all combinations showed a synergistic additive efficacy, and the maximum synergistic coefficient was 1.50 with the mass ratio of pyraclostrobin epoxiconazole as 50:133. Both the indoor and field tests showed that the control efficacy was positively correlated with the established concentration gradient. In the field test with 120 a.i. g/hm2, the control efficacy of pyraclostrobin + epoxiconazole 26% SC was 85.12%, which was better than that of single-agent treatments. The safety evaluation tests showed that all treatments could make different varieties of wheat grow normally without drug damage. This study had shown that the combination of pyraclostrobin and epoxiconazole had a good control efficacy on wheat leaf rust, providing a theoretical basis for the prevention and control of wheat leaf rust and scientific medication in production.
- Control efficacies of nine herbicides to weeds and their safety evaluation in maize fields.
- 作者：暂无 年份期号： 2020-3 刊名：Chinese Journal of Pesticide Science / Nongyaoxue Xuebao 关键词：后茬作物 cauliflower 玉米 radish 安全性 weed control 花椰菜 maize 萝卜 田间防效 post 杂草防除 safety 除草剂 control efficacies harvest crop herbicides
- 描述：In this study, the control efficacies of nine herbicides against weeds were investigated and their safety in the maize field was evaluated. The efficiencies of nine herbicides at the recommended dosages were carried out using the method of spraying stem and leaves in seed production field for sweet maize. Their risk to sweet maize and post-harvest vegetables (cauliflower and radish) was also studied in the experimental field. The results showed that the control efficiencies of nine herbicides on weed and fresh weight were all above 92% at 25 days after the application. The prevention efficacies and 27% nicosulfuron + mesotrione + atrazine OD (810 g a.i./hm2 ) and 25% mesotrione + atrazine OD (750 g a.i./hm2 ) were the best ones. And that of 20% fluroxypyr EC (180 g a.i./hm2 ) was the lowest one, which showed high degree weed coverage after 50 days. In addition, the tested herbicides were safe and had no negative influence on the growth of sweet maize, and some herbicides could even significantly increase the production. The yield of maize after the treatment by 25% mesotrione + atrazine OD，20% nicosulfuron + bromoxynil octanoate OD (300 g a.i./hm2 )，80% atrazine WP (1 440 g a.i./hm2 ) and 27% nicosulfuron + mesotrione + atrazine OD was higher than that treated by other herbicides. Compared with the control, the yields were increased by 21.03%, 19.26%, 18.74% and 16.84%, respectively. Meanwhile, the treatments of 10% mesotrione SC (150 g a.i./hm2 ), 27% nicosulfuron + mesotrione + atrazine OD, 33.5% mesotrione + propisochlor + atrazine SC (1 005 g a.i./hm2 ) and 30% topramezone SC (27 g a.i./hm2 ) could improve the yield of the post-harvest cauliflower and radish. The increasing rates of yields were 18.05% and 13.68%, 3.37% and 12.67%, 15.45% and 11.06%, and 8.21% and 11.67%, respectively. While the 40 g/L nicosulfuron OD (60 g a.i./hm2) had a negative effect on the yield of cauliflower and radish. The yields were decreased by 9.74% and 3.57% compared with the control. The results could provide scientific basis on selecting and applying effective herbicides to control weeds in sweet corn field.
- Comparative analysis of the four formulas commonly used for calculating the control efficacy of fungicides on disease in field trials.
- 作者：暂无 年份期号： 2021-3 刊名：Chinese Journal of Pesticide Science / Nongyaoxue Xuebao 关键词：plant disease Abbott formula 杀菌剂 田间药效试验 control efficacy 病情指数 杨信东公式 disease index Language of English 防治效果 植物病害 field efficacy trials Abbott 公式 Yang Xindong\'s formula Chinese Tilton formula fungicide HendersonTilton 公式 Henderson
- 描述：Field efficacy trials are an indispensable part of pesticide registration management. The applicability, accuracy and effectiveness of the formulas for calculating the control effect of fungicide on plant disease are crucial for the scientific and reasonable evaluation of the field control efficacy of fungicides on plant diseases. At present, the commonly used calculation formulas are different in applicability and calculation errors, but there was no systematic study on the comparison between the commonly used formulas. In this work, four formulas commonly used in field efficacy trials were selected for comparative research. The range of application of the commonly used formulas and the stability of the calculation results were accurately evaluated, and the condition indices observed in the disease index after the treatment were corrected. These results showed that for given disease indexes of the treated groups and the control groups, the four formulas had different sensitivity to the initial difference of disease index between the treated groups and the control groups. When the change of the disease index was extremely small, the results calculated by formula (1), (3) and Yang Xindong\'s formula (4) were not dependence the disease index of the control groups. When the disease index in the treated groups was reduced after treatment, the results from calculated by formula (1) and (3) were out of the range of corrected efficacy. While Henderson-Tilton formula, namely formula (2) in the paper, was used to calculate the control effect based on the rate of change of the disease index before and after treatment, which could effectively avoid the result deviation or the overflow of the range of corrected efficacy. When the initial disease index was higher in the control groups and disease epidemic occurs rapidly, Yang Xindong\'s formula was recommended for calculating the control effect, which could reduce errors caused by the difference in disease index after treatment between the treated groups and the control groups. A comprehensive consideration of various influencing factors before and after treatment in field trials indicated that formula (2) was more applicable under the application of fungicides at the early stage of disease development in field.
- CO2浓度升高对稻田CH4和N2O排放的影响——Meta分析
- 作者：于海洋 年份期号： 2022-3 刊名：中国科学(地球科学) 关键词：CH4 N2O 田间管理措施 CO2浓度升高 稻田 Meta分析
- 描述：CO2浓度升高对稻田生态系统碳（C）氮（N）循环具有重要作用,阐明CO2浓度升高对稻田CH4和N2O排放的影响是农业生产应对全球气候变化的重要组成部分.文章采用Meta分析的方法,讨论了不同CO2浓度升高状况和田间管理措施条件下CO2浓度升高对稻田CH4和N2O排放的影响,结果可为未来气候条件下稻田温室气体减排提供参考.结果表明:整体平均而言,CO2浓度升高显著增加稻田CH4排放（增幅为23%,P<0.05）,同时显著降低稻田N2O排放（降幅为22%,P<0.05）.CO2浓度升高对稻田CH4和N2O排放的影响程度与CO2熏气年限和CO2浓度梯度有关.CO2熏气年限≥10a时,CO2浓度升高同时显著降低稻田CH4和N2O排放,降幅分别为27%和53%（P<0.05）;随CO2浓度梯度上升,CO2浓度升高对稻田CH4排放的促进作用呈现先减弱后增强的趋势,而对稻田N2O排放的影响则由促进作用变为抑制作用.不同N肥施用量、秸秆还田、水分管理和水稻品种等田间管理措施不同程度地影响稻田CH4和N2O排放对CO2浓度升高的响应.无秸秆和半量秸秆还田时,CO2浓度升高显著促进稻田CH4排放（增幅分别为27%和49%,P<0.05）,而全量秸秆还田时,CO2浓度升高对稻田CH4排放无显著影响（P>0.05）;随秸秆还田量的增加,CO2浓度升高对稻田N2O排放的抑制作用不断增强.对比持续淹水,间歇灌溉条件下CO2浓度升高减弱了对稻田CH4排放的促进作用,却增强了对稻田N2O排放的抑制作用.未来CO2浓度升高条件下,建议推广全量秸秆还田和间歇灌溉相结合的稻田管理措施,并辅以优化N肥管理和选育"高产低排"水稻品种等方法,达到最优的"增产减排"效果.此外,有必要进行多尺度、多要素和多方法的综合研究,以期有效降低稻田CH4和N2O排放对CO2浓度升高响应的不确定性.
- Calculation method of load sample size for tractor drive shafts based on dynamic time warping distance.
- 作者：Yin Yiyong 年份期号： 2020-12 刊名：Transactions of the Chinese Society of Agricultural Engineering 关键词：calculation method 载荷样本长度 field test 田间试验 计算方法 tractor drive shaft 拖拉机 dynamic time warping distance 动态时间扭曲距离 load sample size 传动轴
- 描述：Aimed at solving the problem that the traditional engineering methods of determining the load sample size is difficult to adapt to the field test, a method of determining the load sample size based on the Dynamic Time Warping (DTW) distance was proposed to calculate the agricultural machinery field test load sample size. The DTW distance method is mainly applied in voice recognition and online signature verification. It has the characteristics of being able to judge the similarity of unequal length time series and not relying on data statistic features for data similarity judgment. These features are more suitable for calculating the load sample size of agricultural machinery. Firstly, a dynamic load test system was built to obtain the torque load of the tractor drive shaft in the process of ploughing, and the small load data which was lower than 10% of the maximum load cycle was filtered. According to characteristics of the agricultural machinery operation and the tractor drive shaft load, the ploughing condition and the adjustment condition were regarded as a complete operation cycle, which ensured that these operation cycles meet ergodicity test. Moreover, traditional approximate mean accuracy estimation method and fitting curve of mean method were selected to determine the load sample size of the tractor drive shaft under ploughing condition and the results were 8 subsamples and 3 subsamples, respectively. After normalizing the load time series with different numbers of operation cycles, the DTW distance between them and the maximum number of operating sections were calculated. The results displayed that load sample size determined by DTW distance method was 16 subsamples. Furthermore, since the actual measured load cannot represent the whole life load of components, in practice, the measured load samples need to be statistically analyzed and then combined with the extrapolation formula to extrapolate the load to obtain the full life load spectrum. The accuracy of the whole life load spectrum is mainly related to the extrapolation method and the selected sample length. Therefore, under the same error condition, the commonly used parameter extrapolation was selected to verify the load sample size. On the premise that the confidence level was 95% and the goodness of fit is greater than 0.9, the fitting parameters of the double normal distribution function about the mean load and its frequency were obtained. The value of fitting function obtained from the whole measured load used as the reference value, and the relative errors between the reference value and the above fitting parameters were calculated. The results showed that the relative errors of the fitting parameters through the load sample size with the DTW distance method could be guaranteed to be within 10%. Using the double normal distribution function for mean load and its frequency fitting, the maximum relative errors of fitting parameter for the approximate mean precision estimation method and the mean curve were 126.06% and 80.62%, respectively, while the maximum value of the relative error of the fitting parameters based on the DTW distance calculation method was 5.43%, which verified the applicability of the load sample size calculation method based on the DTW distance. The calculation method can be used for the field test load size of tractor drive shafts in the future.