喷雾参数对自走式喷杆喷雾机稻田喷雾农药利用率及雾滴沉积分布的影响

比较在不同喷雾压力和施药液量条件下,采用自走式喷杆喷雾机在水稻分蘖期、孕穗期、扬花期进行喷雾处理的农药利用率、沉积分布均匀性及水稻茎基部雾滴密度的差异,为建立自走式喷杆喷雾机在稻田的高效施药技术提供理论依据。以生物染料丽春红-G作为农药示踪剂,估测不同喷雾参数的农药利用率,并用变异系数、绝对份额比例值比较农药分布的均匀性。同时通过水敏纸收集水稻基部雾滴密度,分析不同喷雾参数下农药雾滴穿透水稻冠层的能力。结果表明:在水稻分蘖期,采用自走式喷杆喷雾机在喷雾压力为1.2 MPa、施药液量为375 L/hm^2条件下喷雾,每个采样点的丽春红-G的平均沉积量仅为0.11 mg,与喷雾压力为0.4 MPa、施药液量为300 L/hm^2条件下喷雾的沉积量相比减少了56.00%。在水稻孕穗期,当喷雾压力为1.2 MPa、施药液量为375 L/hm^2时进行喷雾处理,每个采样点的丽春红-G的平均沉积量达0.26 mg,显著高于其他4个处理。在水稻扬花期,不同喷雾参数间的沉积量差距减小。在合适的喷雾压力和施药液量时,自走式喷杆喷雾机在水稻分蘖期、孕穗期和扬花期进行喷雾处理,农药利用率分别达到40.57%、54.97%和55.50%。综合变异系数和绝对份额比例两个指标,采用自走式喷杆喷雾机在喷雾压力为0.8 MPa、施药液量为300 L/hm^2条件下喷雾,农药分布更均匀。喷雾压力对水稻基部雾滴密度有显著影响,在水稻生长中后期,当喷雾压力低于0.8 MPa、施药液量为225~375 L/hm^2时,水稻茎秆基部雾滴密度均小于30个/cm^2。研究结果表明,喷雾压力和施药液量对自走式喷杆喷雾机稻田喷雾的农药利用率、分布均匀性及水稻茎秆基部雾滴密度有显著影响。在水稻生长前期,不宜采用高压力大水量喷雾作业;在水稻生长中后期,为增加对水稻基部病虫害的防治效果,需提高喷雾压力。     

叶片倾角、雾滴大小与施药液量对毒死蜱在水稻植株沉积的影响

为提高农药的有效利用率,用丽春红为示踪剂研究了毒死蜱药液在水稻叶片上的沉积特性.随着水稻叶片的倾角变小,毒死蜱的沉积量相应地减少.用体积中径(VMD)为149.5 μm的雾滴处理,在设定叶片倾角为90°、60°、30°时,毒死蜱沉积量分别是直立叶片上沉积量的10.2、5.8、2.9倍.随着叶片倾角变小,雾滴VMD对沉积的影响增大,在90°、60°、30°、0°四个叶片倾角,用VMD149.5 μm雾滴处理的沉积量分别是用VMD 233.7 μm雾滴处理沉积量的1.5、2.1、3.3、5.5倍.在施药液量170～1.36×103L/hm2范围内,毒死蜱沉积量随施药液量的增加而减少.用浓度为800mg/L毒死蜱药液在水稻叶片上测定的最大稳定持留量约为4.66μg/cm2.结果表明,采用小雾滴与低容量喷雾,可显著提高毒死蜱在水稻叶片的沉积量.     

雾滴大小与施药液量对草甘膦在空心莲子草叶片沉积的影响

为提高草甘膦防治空心莲子草Alternanthera philoxeroides时药剂的有效利用率,用丽春红S为示踪剂研究了草甘膦药液在空心莲子草叶片的沉积特性。结果表明,用体积中径(VMD)149.5~233.7 μm的雾滴喷雾,草甘膦在空心莲子草叶片上的沉积量在体积中径为157.3 μm时最多,随着雾滴体积中径增大,沉积量减少。雾滴体积中径157.3 μm与施药液量339 L/hm2处理的沉积量是雾滴体积中径233.4 μm与施药液量694.5 L/hm2处理的1.54倍。施药液量超过382.5 L/hm2时,草甘膦药液的流失明显增多。800 mg/L草甘膦药液在空心莲子草叶片上的最大稳定持留量约为 4.92 μg/cm2。结果表明,喷雾施药时采用小雾滴和较低施药液量,可大幅度提高草甘膦在空心莲子草上的沉积量。     

植保无人机低空低容量喷雾在茶园的雾滴沉积分布及对茶小绿叶蝉的防治效果

为研究植保无人机低空低容量喷雾技术在实现茶园农药减量中的作用,通过在茶园喷施20%吡虫啉可湿性粉剂,比较其与传统大容量喷雾技术对茶小绿叶蝉Empoasca flavescens的防治效果。结果表明,使用3种植保无人机喷雾,安装有TEEJET110015#喷头的植保无人机的雾滴沉积密度为24.1～127.4个/cm~2,平均值为75.8个/cm~2,沉积量为0.002～1.15μg/cm~2,均值0.58μg/cm~2;安装有TEEJET11001#喷头的植保无人机的雾滴沉积密度为15.0～80.4个/cm~2,平均值为47.7个/cm~2,沉积量均值为0.01～1.38μg/cm~2,均值0.70μg/cm~2;安装有TEEJET11003#喷头的植保无人机的雾滴沉积密度为9.2～18.2个/cm~2,平均值为13.7个/cm~2;沉积量为0～1.14μg/cm~2,均值0.57μg/cm~2。农药利用率为49.3%～58.2%。使用3种传统器械喷雾,担架式动力喷雾机喷雾得到的沉积量为0.02～0.30μg/cm~2,均值0.16μg/cm~2,背负式手动喷雾器喷雾得到的沉积量为0.01～0.46μg/cm~2,均值0.23μg/cm~2,背负式电动喷雾器喷雾得到的沉积量为0.01～0.65μg/cm~2,均值0.33μg/cm~2。农药利用率为33.7%～39.6%。结果表明,3种植保无人机喷雾的农药沉积量和利用率均高于3种传统的施药器械,但其喷雾的均匀性还有待提高。施药后4 d,植保无人机低空低容量喷雾对茶小绿叶蝉防治效果为85.8%～90.4%,传统大容量喷雾对茶小绿叶蝉防治效果为91.8%～93.2%,两者差异不显著。药后10 d,前者对茶小绿叶蝉防治效果为72.9%～75.6%,后者防治效果为65.8%～71.6%,说明植保无人机低空低容量喷雾对茶小绿叶蝉的防治效果优于传统大容量喷雾。研究结果表明,植保无人机低空低容量喷雾有着更长的持效期,为茶园的农药减施增效提供了可能性。     

不同助剂、喷头及喷雾压力对自走式喷杆喷雾机稻田喷雾效果的影响

以亿丰丸山3WP-500CN型号自走式喷杆喷雾机为研究对象，以诱惑红85作为指示剂，测定了6种喷雾助剂 (红太阳、倍力、迈丝、融透、印楝油和哈速腾)、3种喷头 (TEEJET-VP80015、ASJ-VP110015和LICHENG-VP11003) 以及3种喷雾压力 (0.2、0.4 和0.6 MPa) 对农药沉积利用率、药液雾化性能 (D₅₀值雾滴密度等)、雾滴分布均匀性等喷雾参数的影响，以及240 g/L噻呋酰胺悬浮剂对水稻纹枯病防治效果及水稻产量的影响。结果表明:采用TEEJET-VP80015喷头，在0.4 MPa喷雾压力条件下，助剂哈速腾雾滴分布均匀性显著高于其他助剂，变异系数为0.11，同时对雾滴估计沉积量 (45.74 μL/cm2) 与分布跨度 (1.29) 的影响显著高于其他助剂；助剂迈丝对雾滴密度 (103.78个/cm2) 和农药沉积利用率 (83.88%) 的影响均显著高于其他助剂。采用TEEJET-VP80015喷头，在未添加助剂条件下，不同喷雾压力对雾滴分布跨度、雾滴附着率和农药沉积利用率影响差异显著，其中在0.6 MPa压力下，分布跨度为1.18，雾滴附着率为33.32%，农药沉积利用率为78.19%。在未添加助剂、0.4 MPa喷雾压力条件下，喷头LICHENG-VP11003对雾滴分布均匀性的影响显著高于另外两种喷头，变异系数为0.12，同时对雾滴覆盖率 (69.37%)、雾滴估计沉积量 (42.77 μL/cm2) 和农药沉积利用率 (75.79%) 的影响也显著高于另外两种喷头。各测定条件下，240 g/L噻呋酰胺悬浮剂对水稻纹枯病的防治效果与雾化性能和雾化参数结果一致，其中添加助剂迈丝后防治效果达到89.27%，显著高于添加其他助剂，增大喷雾压力到0.6 MPa，防治效果达到88.67%，显著高于其他压力条件；采用TEEJET-VP80015喷头，在0.4 MPa喷雾压力下，水稻产量为8301 kg/hm2，显著高于人工喷雾。因此，助剂与喷头类型均对自走式喷杆喷雾机施药时的农药沉积利用率、雾滴分布均匀性以及雾滴参数和雾化效果有显著的影响，在适当的喷雾压力下添加助剂可提高农药的防治效果。     

喷雾助剂及施液量对植保无人机喷雾雾滴在水稻冠层沉积分布的影响

为提高农药沉积率,利用黏度计、表面张力仪、药液润湿性测试卡、激光粒度仪测定不同喷雾助剂添加量对蒸馏水溶液性质的影响,并分析喷雾助剂及施液量对水稻冠层不同位置雾滴沉积密度、沉积量以及有效沉积率的影响。结果表明,添加喷雾助剂对蒸馏水溶液的性质有显著影响,与蒸馏水相比,当添加喷雾助剂为0.5%和1.0%时,雾滴体积中径变为108.9、98.7μm,表面张力降低64.7%、64.9%,黏度增加为2.3、2.3 m Pa·s,铺展系数为蒸馏水的74.5、58.5倍,能有效促进雾滴铺展并避免药液流失;植保无人机喷施试验结果显示,增加施液量可显著提高雾滴沉积密度,添加喷雾助剂可以显著提高雾滴沉积量以及有效沉积率,当施药量为13.5 L/hm~2且添加1.0%喷雾助剂时,雾滴在水稻冠层的有效沉积率最大,为48.9%。     

喷头类型对棚室黄瓜叶片的药液沉积和白粉病防治效果的影响

为明确喷头类型对棚室黄瓜叶片药液附着和白粉病防治效果的影响,采用茎叶喷雾法测定了雾滴体积中径(VMD)对药液沉积量、最大持留量的影响以及氟硅唑对黄瓜白粉病的防治效果。结果表明,在黄瓜叶片上,氟硅唑的沉积量随着雾滴VMD增大而降低,雾滴VMD为191、213、250μm时的沉积量分别比160μm时降低了19.15%、11.76%和38.25%;当药液量为320 L/hm2时,氟硅唑在黄瓜叶片上的沉积效率最高,为63%;浓度为50 mg/L的氟硅唑在叶片上的最大稳定持留量约为5.15μL/cm2;不同浓度氟硅唑对黄瓜白粉病的防治效果差异显著,有效成分用量为90g/hm2时的防治效果最好,达90.09%;当氟硅唑浓度一定时,不同喷头类型对黄瓜白粉病的防治效果差异显著,当有效成分用量为60、75 g/hm2时,采用喷头F110-015的防治效果最好,分别达70.64%和81.15%。研究表明,防治黄瓜白粉病应选择雾滴粒径小的喷头,且浓度较高的氟硅唑可大幅度提高其有效利用率和防治效果。     

添加助剂对植保无人飞机低容量喷雾在矮化密植苹果园中雾滴沉积分布及苹果黄蚜防治效果的影响

为明确助剂在农药减施增效中的作用,于室内利用自动界面张力仪、接触角仪、激光粒度仪、药液润湿性测试卡测定药液中添加助剂对溶液性质的影响,并结合田间试验探究药液中添加助剂对矮砧纺锤形栽培模式苹果园果树冠层喷雾雾滴沉积分布及苹果黄蚜Aphis spiraecola防治效果的影响。结果表明,植保无人飞机低容量喷雾常规用量毒死蜱乳油时,添加体积分数为0.5%的助剂后,溶液性质相比蒸馏水发生了显著变化,溶液的表面张力由71.2 mN/m下降到31.7 mN/m,下降了55.5%;喷雾20 s后在苹果叶片上的接触角减小到13.8°,比蒸馏水在苹果叶片上的接触角减少了74.3%;雾滴体积中径由蒸馏水的122.4μm显著增加到142.2μm;药液的铺展系数是蒸馏水的4.0倍。添加助剂后可以有效减少雾滴漂移,增加雾滴在苹果叶片上的铺展。田间使用植保无人飞机喷施40%毒死蜱乳油的沉积量均值为0.79μg/cm~2,7 d后对苹果黄蚜的防治效果为72.9%;农药减施20%后的沉积量均值为0.70μg/cm~2,7 d后对苹果黄蚜的防治效果为71.5%;而在这2个处理中添加0.5%助剂后农药沉积量均值分别增加至1.89μg/cm~2和1.14μg/cm~2,7 d后对苹果黄蚜的防治效果分别为83.8%和77.0%。表明添加助剂可显著增加农药在果树上的沉积量及对苹果黄蚜的防治效果;即使在农药减量20%应用中添加助剂后,药液在果树冠层的沉积量以及对苹果黄蚜的防治效果依然高于农药常规用量处理。     

核桃园植保无人机作业参数优选

为探究植保无人机在核桃园低空低容量喷雾最优作业参数,本文采用三因素三水平正交试验设计,研究了植保无人机喷雾后核桃树上雾滴沉积分布情况。结果表明:影响雾滴覆盖密度和沉积量的主要因素是飞行速度,其次是飞行高度和施药液量;在树高6～7 m的核桃园中植保无人机喷雾效果较优的作业参数是飞行速度2.2～3.0 m/s,飞行高度2.0～2.5 m,施药液量22.5～30.0 L/hm~2,其平均雾滴覆盖密度和沉积量分别为26.36～37.94个/cm~2、0.24～0.29μg/cm~2;不同冠层雾滴覆盖密度和沉积量分布为上层中层下层,外围内膛;喷头型号对雾滴覆盖密度和雾滴直径有显著影响;中等喷头(Teejet110015)处理的沉积量最大,但粗、中、细3种喷头处理间的沉积量无显著性差异;植保无人机和地面人工+机动喷杆喷雾的农药地面流失率分别为3.61%和23.69%,两处理间有显著性差异。本文对无人机在核桃园喷雾作业参数进行了优选,可为无人机对高冠果树的合理喷施、提高喷施效果提供参考和指导。     

冠层推拨装置对喷杆喷雾机雾滴飘失与沉积特性的影响

喷杆喷雾机具有作业效率高、雾滴覆盖率高、沉积分布均匀、防治效果好等优点,是目前大田作物最主要的施药机具。但受作物冠层遮挡和侧风等气象条件的影响,导致喷杆喷雾机作业时雾滴难以穿透到植株中下部并伴随飘失。为改善喷杆喷雾机喷雾雾滴在作物冠层的穿透性并降低飘移量,本文优化设计了一种适用于大田作物的喷杆喷雾机冠层推拨装置。并分别使用两种喷头(标准扇形雾喷头ST110-02、射流喷头IDK120-02)对该装置的减飘性和在小麦上的沉积特性进行了对比试验。结果表明:该冠层推拨装置对标准扇形雾喷头ST110-02的减飘效果强于射流喷头IDK120-02,其减飘效果分别为59.0%和9.5%;冠层推拨装置可以提高药液的沉积率,对于ST110-02喷头可增加18.0%,IDK120-02喷头增加了8.6%;同时该推拨装置对小麦植株的推拨作用增加了雾滴向冠层中下方的穿透效果,有利于药液在植株上的均匀沉积。     

Effects of nozzle type and spray angle on spray deposition in ivy pot plants

BACKGROUND: Fewer plant protection products are now authorised for use in ornamental growings. Frequent spraying with the same product or a suboptimal technique can lead to resistance in pests and diseases. Better application techniques could improve the sustainable use of the plant protection products still available. Spray boom systems—instead of the still predominantly used spray guns—might improve crop protection management in greenhouses considerably. The effect of nozzle type, spray pressure and spray angle on spray deposition and coverage in ivy pot plants was studied, with a focus on crop penetration and spraying the bottom side of the leaves in this dense crop. RESULTS: The experiments showed a significant and important effect of collector position on deposition and coverage in the plant. Although spray deposition and coverage on the bottom side of the leaves are generally low, they could be improved 3.0–4.9‐fold using the appropriate application technique. CONCLUSIONS: When using a spray boom in a dense crop, the nozzle choice, spray pressure and spray angle should be well considered. The hollow‐cone, the air‐inclusion flat‐fan and the standard flat‐fan nozzle with an inclined spray angle performed best because of the effect of swirling droplets, droplets with a high momentum and droplet direction respectively. Copyright © 2010 Society of Chemical Industry     

Effect of spray application technique on spray deposition in greenhouse strawberries and tomatoes

BACKGROUND: Increasingly, Flemish greenhouse growers are using spray booms instead of spray guns to apply plant protection products. Although the advantages of spray booms are well known, growers still have many questions concerning nozzle choice and settings. Spray deposition using a vertical spray boom in tomatoes and strawberries was compared with reference spray equipment. Five different settings of nozzle type, size and pressure were tested with the spray boom. RESULTS: In general, the standard vertical spray boom performed better than the reference spray equipment in strawberries (spray gun) and in tomatoes (air‐assisted sprayer). Nozzle type and settings significantly affected spray deposition and crop penetration. Highest overall deposits in strawberries were achieved using air‐inclusion or extended‐range nozzles. In tomatoes, the extended‐range nozzles and the twin air‐inclusion nozzles performed best. Using smaller‐size extended‐range nozzles above the recommended pressure range resulted in lower deposits, especially inside the crop canopy. CONCLUSIONS: The use of a vertical spray boom is a promising technique for applying plant protection products in a safe and efficient way in tomatoes and strawberries, and nozzle choice and setting should be carefully considered. Copyright © 2009 Society of Chemical Industry     

山地管道恒压喷雾中喷雾压力和孔径对雾滴粒径的影响

为提高农药利用率,研究山地果园管道恒压喷雾系统中喷雾压力和孔径对雾滴粒径参数的影响,利用激光粒度仪,测量3种孔径空心圆锥雾喷头在8种压力下的6种雾滴粒径参数数据,分析各粒径级雾滴的分布情况,给出雾滴粒径大小及其随压力和孔径的变化趋势,进行了雾滴参数的多元线性回归,建立基于压力的雾滴参数模型。结果表明:粒径大于100μm的雾滴(小于0.3%)和粒径为0~20μm的雾滴(小于0.5%)可忽略不计,雾滴粒径主要分布于20~40μm(79.5%~92.8%);雾滴均较细小,全部为气溶胶;孔径越小,压力越大,雾滴越细小;6种雾滴粒径参数与孔径和压力均有良好的二元线性关系(R2分别为0.928、0.956、0.949、0.949、0.889和0.815);6种雾滴粒径参数均随压力呈二次多项式变化规律,决定系数R2均达到了0.894以上。研究结果对山地果园管道恒压喷雾中喷头的选型、喷雾压力的调整及喷雾效果的优化有重要参考意义。     

飞防助剂和施药液量对植保无人飞机喷施雾滴沉积和棉花蓟马防效的影响

为明确飞防助剂和施药液量对植保无人飞机喷施在棉花冠层的雾滴沉积和对棉花上蓟马防效的影响,选择倍达通、功倍、杰效丰和迈丝4种飞防助剂,设置3种施药液量,通过田间试验研究了植保无人飞机喷施25%噻虫嗪水分散粒剂后其在棉花冠层的雾滴密度、覆盖率、沉积量和雾滴均匀性以及对棉花上蓟马的防效。结果表明,4种飞防助剂和3种施药液量对植保无人飞机喷施的雾滴沉积和蓟马防效均有显著影响。增加施药液量可显著增加雾滴在棉花冠层的密度与覆盖率,添加飞防助剂对雾滴密度的提升效果显著。4种助剂对农药雾滴在棉花冠层上、中、下部的覆盖率的影响趋势较为一致,与棉花冠层上部相比,对中、下部位覆盖率的影响较低。施药液量为2 L/667 m²时,添加倍达通、功倍、杰效丰、迈丝及无助剂对照的雾滴穿透性分别为46.0%、49.1%、33.6%、36.1%和44.3%,该施药液量下各处理雾滴穿透性均较好。随着施药液量增加,药后1、3、7 d对棉花蓟马的防效也显著提升。在相同施药液量下,25%噻虫嗪水分散粒剂药液中添加飞防助剂倍达通和杰效丰相较于功倍和迈丝,对棉花蓟马具有更高的防治效果。试验结果为植保无人飞机防治...     

Effect of spray volume on the deposition, viability and infectivity of entomopathogenic nematodes in a foliar spray on vegetables

BACKGROUND: Spray volume can influence the amount of free water on the leaf surface and subsequently the ability of entomopathogenic nematodes (EPNs) to move. In this study, an investigation was made of the effect of spray volume (548, 730 and 1095 L ha⁻¹) on the deposition, viability and infectivity of EPNs against Galleria mellonella on savoy cabbage, cauliflower and leek. RESULTS: Increasing spray volume decreased nematode deposition on 7.1 cm² leek leaf discs at a 15° angle with the spray nozzle. Although the number of living nematodes observed on leek after 240 min of exposure was not significantly different between the low-volume application (548 L ha⁻¹) and the high-volume application (1095 L ha⁻¹), a greater infectivity was obtained in the latter application. The higher number of droplets deposited on the leek discs in the high-volume application may have stimulated nematode movement. No significant effect of spray volume was observed on the relative deposition of Steinernema carpocapsae on the bottom side of cauliflower and savoy cabbage leaf discs. In spite of the low S. carpocapsae deposition on the bottom side of the savoy cabbage discs, high infectivity was obtained against G. mellonella. Using the lowest spray volume on savoy cabbage, infectivity decreased with increasing exposure time, while infectivity was not affected by exposure time when a spray volume of 730 L ha⁻¹ or more was used. CONCLUSION: Spray volume is an important application parameter, as it affects nematode infectivity. Future research should investigate the effect of spray volume in the field and its influence on the effect of adjuvants. Copyright © 2012 Society of Chemical Industry     

一种基于智能手机的航空喷雾质量检测系统研发及应用

为改进和优化航空喷雾作业质量检测技术,进一步提高检测准确性与效率,本文通过对比分析国内外雾滴采集与检测技术,提出了基于智能手机拍照方式获取雾滴沉积图像,并利用数字图像处理技术,测算雾滴体积直径的新方法。设计开发了基于智能手机的航空喷雾质量检测系统(J-02),该系统主要包括便携式检测仪、专业检测软件、数据管理平台三部分。最后,通过与雾滴沉积分析系统(IDAS PRO)和显微镜(Leica M80)等传统检测手段对比测试验证表明,基于智能手机的航空喷雾质量检测系统适用于航空喷雾质量现场检测,且检测结果准确可靠。     

Reduced spray programs for Drosophila suzukii management in berry crops

Since the arrival of Drosophila suzukii M. (Diptera: Drosophilidae), field applications of broad-spectrum insecticides have increased in berry crop production to protect susceptible fruits from infestation. Field studies were conducted from 2011 to 2013 to determine whether alternate row middle or border spray programs could manage D. suzukii as well as complete sprays and have less of an impact on non-target arthropods. Four raspberry sites and one blueberry site were alternate row middle and border sprayed, respectively. Adult and larva counts of D. suzukii were compared to conventional complete spray programs. Non-target arthropods were evaluated 7 d post-harvest. In both reduced spray trials, no differences in mean adult numbers and larvae of D. suzukii were detected between treatments. Mean counts immediately after sprays (i.e. 3–12 d after treatment) were also similar in complete and alternate row sprays. Both reduced spray strategies had significantly more Stethorus spp.; additionally, alternate row sprays had significantly more Psyllobora spp. These reduced pesticide strategies are additional tools to consider in D. suzukii IPM programs that can reduce the area sprayed, application time, and input costs while conserving natural enemies.     

Effect of the spray application technique on the deposition of entomopathogenic nematodes in vegetables

BACKGROUND: The present study compared entomopathogenic nematode delivery at the base of savoy cabbage and cauliflower, at the lower side of savoy cabbage and cauliflower leaves and in leek stems and the ground deposition using a five‐nozzle spray boom equipped with an ISO 08 flat fan, an air induction flat fan and Twinjet spray nozzles. Additionally, an air support system and a row application system were evaluated. RESULTS: Approximately 40% of the applied nematodes did not reach the foot of the cabbage plants. The use of an air support system or a row application system improved nematode deposition at the savoy cabbage base. Relative nematode deposition on the lower side of savoy cabbage leaves was 27.20%, while only 2.64% of the applied nematodes reached the lower side of cauliflower leaves. After spraying leek with a standard boom, a low relative nematode deposition (26.64%) was measured in the leek stem. Nozzle type affected the distribution of nematodes in droplet spots. CONCLUSION: Nozzle type has a minor effect on the number of entomopathogenic nematodes delivered on difficult‐to‐reach targets. The use of modified spray application techniques directing the spray to the target site are necessary to increase the chances of contact of entomopathogenic nematodes with their target. Copyright © 2011 Society of Chemical Industry     

Field evaluation of a self-propelled sprayer and effects of the application rate on spray deposition and losses to the ground in greenhouse tomato crops

BACKGROUND: In the greenhouses of south‐eastern Spain, plant protection products are applied using mainly sprayers at high pressures and high volumes. This results in major losses on the ground and less than uniform spray deposition on the canopy. Recently, self‐propelled vehicles equipped with vertical spray booms have appeared on the market. In this study, deposition on the canopy and the losses to the ground at different spray volumes have been compared, using a self‐propelled vehicle with vertical spray booms versus a gun sprayer. Three different spray volumes have been tested with a boom sprayer, and two with a spray gun. RESULTS: The vehicle with the vertical spray boom gave similar depositions to those made with the gun, but at lower application volumes. Also, the distribution of the vertical spray boom was more uniform, with lower losses to the ground. CONCLUSIONS: The vertical spray booms used in tomato crops improve the application of plant protection products with respect to the spray gun, reducing the application volumes and the environmental risks of soil pollution. Copyright © 2011 Society of Chemical Industry