摘要
为明确农药雾滴在成熟期烟草叶片上有效沉积的关键影响因子,提高病害的防控效果和减少农药污染,利用Canny边缘检测、Zisman和微量称重检测等方法分别测定了成熟期烟草叶片的临界表面张力、不同叶倾角与喷雾距离下的流失点(Point of Runoff,POR)和最大稳定持留量(Maximum Retention,R_(m))。结果表明:(1)药液表面张力与接触角的余弦值呈显著负相关,烟草(红花大金元)叶片的临界表面张力较小,为31.44 mN/m。(2)上部叶倾角大,集中在60°~70°之间;下部叶倾角小,集中在20°~40°之间;中部叶居中,集中在50°~60°之间。(3)流失点与最大稳定持流量受叶倾角和喷雾距离影响。不同叶倾角的流失点相差较大,可达30%~43%,流失点与叶倾角呈显著负相关。20°~30°倾角的叶片在喷雾距离为50 cm时的流失点最高,平均为28.0μL/cm^(2),比其他距离的处理高约50%;喷雾距离大于100 cm时,流失点和最大稳定持留量变化不大。40°~70°倾角的叶片流失点和最大稳定持留量在不同喷雾距离下基本保持不变。因此,烟草叶片喷施农药时应添加助剂以降低药液的表面张力至其临界表面张力以下,以增强药液润湿和展布能力;施药时下部叶的喷雾距离>100 cm,中、上部叶的喷雾距离>50 cm;施药量应控制在流失点以内。
In order to evaluate key factors affecting the effective deposition of pesticide droplets on tobacco leaves during pesticide spray,so as to improve disease control efficiency and reduce pesticide pollution,parameters such as critical surface tension,point of runoff(POR)and maximum retention(R_(m))on mature tobacco leaves at different spray distances and leaf inclination angles were measured by the Canny edge detection algorithm,Zisman method and micro-weighing detection method.The results showed that:1)There was a significant negative correlation between the surface tension of pesticide liquid and the cosine values of the contact angle.The critical surface tension of mature tobacco(cv.Honghuadajinyuan)leaves was 31.44 mN/m.2)The inclination angles of upper leaves were larger and mainly in the range of 60°-70°,while those of lower leaves were smaller and mainly in the range of 20°-40°,and those of middle leaves were mainly in the range of 50°-60°.3)POR and Rmvalues were affected by the leaf inclination angle and spray distance.The differences of POR among different leaf inclination angles were quite big and reached 30%-43%.POR significantly negatively correlated with the leaf inclination angle.With the mean value of about 28μL/cm^(2),POR was the highest at the spray distance of 50 cm and the leaf inclination angle of 20°-30°,which was nearly 50%higher than that at other distances.POR and Rmvalues changed slightly at spray distances larger than 100 cm.The POR and Rmof leaves with inclination angles of 40°-70°basically remained unchanged at different spray distances.Therefore,additives were necessary during spraying pesticides on tobacco leaves for reducing the surface tension of pesticide droplets to a level lower than the critical surface tension and for promoting the wetting and spreading abilities of the sprayed pesticides.The recommended spray distance for lower leaves was larger than 100 cm,and those for middle and upper leaves were larger than 50 cm,and the application dosage of pesticide should be
作者
李莫飞
王志江
吕明站
王挥华
谢永辉
郭宜秀
詹莜国
LI Mofei;WANG Zhijiang;LÜ Mingzhan;WANG Huihua;XIE Yonghui;GUO Yixiu;ZHAN Youguo(Yunnan Innovation Institute of Beihang University,Kunming 650233,China;Kunming Branch of Yunnan Provincial Tobacco Company,Kunming 650051,China)
出处
《烟草科技》
CAS
CSCD
北大核心
2022年第3期25-30,共6页
Tobacco Science & Technology
基金
中国烟草总公司云南省公司科技计划重点项目“基于无人机的智能技术在烟草农业的集成与应用”(2020530000241029)。
