3类功能助剂对酥梨的安全性及其对 重要害虫防效的影响

为明确3类不同功能助剂在酥梨园的安全使用技术及其对梨园重要害虫防效的影响, 在田间梨树不同发育期, 调查3类?共6种功能助剂对果实和叶片的药害率; 调查3种安全助剂与4种农药混配后对梨小食心虫和梨木虱的防效?结果表明, 6种功能助剂对梨果药害率从高到低依次为15 d幼果?45 d小果和75 d膨大期果实; 6种助剂对叶片均安全?在较低温度下施药可显著降低功能助剂对梨果的药害率?6种助剂对果实药害率从高到低依次为NF100?Silwet 408?GY-Tmax?GY-T1602? GY-T12和迈道?迈道?GY-T12显著提高22.4%螺虫乙酯悬浮剂?20%呋虫胺可溶粒剂和5%阿维菌素微乳剂对梨木虱的防效, GY-T1602显著提高了22.4%螺虫乙酯悬浮剂和20%呋虫胺可溶粒剂的对梨木虱的防效; 迈道?GY-T12和GY-T1602显著提高了5%阿维菌素微乳剂?20%呋虫胺可溶粒剂和4.5%高效氯氰菊酯微乳剂对梨小食心虫的防效?该结果为功能助剂在酥梨园的安全使用提供了科学依据?     

喷雾助剂对氟啶虫胺腈在富士苹果叶片表面润湿和持留的影响

为明确喷雾助剂在苹果园化学防治中的作用，采用表面张力、接触角和最大稳定持留量等分析了GY-T12、NF-100和迈润等3种喷雾助剂在达到临界胶束浓度 (CMC) 时对22%氟啶虫胺腈悬浮剂药液的表面张力及其在苹果叶片表面润湿性能和持留量的影响。结果显示:当添加的3种喷雾助剂达到其CMC时，氟啶虫胺腈药液表面张力降低至27.64~35.64 mN/m；根据水滴在苹果叶片表面的接触角小于或大于90°判定苹果叶片近轴面为亲水性表面、远轴面为疏水性表面，添加助剂使药液在近轴面和远轴面30 s的静态接触角分别降低23.2°~41.3°和68.0°~93.5°，同时使亲水性近轴面黏附功降低5.36~12.56 mJ/m2，而黏附张力增大9.27~11.26 mN/m，在疏水性远轴面黏附功与黏附张力分别增大27.45~36.66 mJ/m2和47.55~53.28 mN/m，对改善远轴面的黏附润湿性更显著；药液表面张力和最大稳定持留量存在抛物线状函数关系，当表面张力为40.89 mN/m时，持留量达最大值12.53 mg/cm2；3种助剂中，NF-100和GY- T12可显著增加药液持留量，且GY-T12对靶标害虫苹果黄蚜有显著增效作用。本研究结果表明，在苹果园应用时应依据预期目标选择适当的喷雾助剂，并通过调节药液表面张力使其处于适宜范围以增加药液持留量、提高对靶标害虫的毒力。     

7种助剂对7种稻田除草剂的减量增效作用

为明确矿物油、激健、GY-T1602、GY-WS10、GY-W07、GY-S903和NF-100等7种助剂对双草醚、噁唑酰草胺、氰氟草酯、五氟磺草胺、二氯喹啉酸、双唑草腈、嘧啶肟草醚等7种水稻田常用除草剂的减量增效作用,采用整株生物测定法测定除草剂桶混不同助剂对稗草的防效及其对水稻的安全性。结果表明,矿物油、激健、GY-T1602、GY-S903、GY-WS10和NF-100等6种助剂对嘧啶肟草醚、双草醚和氰氟草酯等3种水稻除草剂具有减量增效作用,可减量25～50%;供试7种助剂对五氟磺草胺、噁唑酰草胺、二氯喹啉酸和双唑草腈等4种除草剂均无显著增效作用。根据生物测定结果筛选了11种具有良好减量增效作用的除草剂+助剂组合,分别为双草醚+GY-W07/GY-WS10/GY-S903/矿物油/激健;嘧啶肟草醚+GY-T1602/GY-WS10/NF-100;氰氟草酯+GY-T1602/GY-S903/激健。     

20%呋虫胺可溶粒剂防治甘蔗螟虫和绵蚜田间药效试验

为明确20%呋虫胺SG用于大田防治甘蔗螟虫和绵蚜的防治效果,开展了该药的田间药效试验。结果表明,在甘蔗下种时每公顷施用20%呋虫胺SG 180~240g,对苗期甘蔗螟虫的防效最高可达100%,对甘蔗绵蚜的防效均达95%以上,且持效期长,与25%噻虫嗪WG的防效无显著差异,是防治甘蔗螟虫和绵蚜的高效低毒的理想药剂。     

PDMS系列助剂对10%甲维盐·氯虫苯甲酰胺悬浮剂防治草地贪夜蛾的增效作用

本研究采用室内毒力测定, 助剂润湿铺展性能和田间防治效果评价研究了自研“PDMS”系列助剂（PDMS-01、PDMS-02、PDMS-03、PDMS-04）对10%甲维盐·氯虫苯甲酰胺悬浮剂防治草地贪夜蛾的增效作用。结果表明, PDMS系列助剂均可提高10%甲维盐·氯虫苯甲酰胺悬浮剂的毒力;7.5~17.5 g/L处理药液中添加助剂PDMS-01, 药液润湿时间降低172.84～176.59 s, 药液表面张力降低15.26~16.28 mN/m, 玉米叶片正、背面静态接触角分别降低13.39°~24.12°和12.02°~27.56°;10%甲维盐·氯虫苯甲酰胺悬浮剂减量30%（21 g/667m 2）并添加PDMS-01后, 无人机施药对草地贪夜蛾的3 d和14 d田间防效分别可达76.62%和82.36%, 与未减量处理（30 g/667m 2）的防效差异不显著, 与添加KQ-103、凯耀高航处理差异也不显著。助剂PDMS-01可显著改善10%甲维盐·氯虫苯甲酰胺悬浮剂药液的润湿铺展性能, 减少药剂用量30%对草地贪夜蛾仍有较高防效, 且速效性和持效性较好。     

氟啶虫胺腈与其他药剂复配对苹果黄蚜的联合毒力及效果评价

针对苹果黄蚜防治药剂类型单一、药剂敏感性下降等问题,采用浸叶法开展几种药剂对苹果黄蚜室内毒力测定,并用共毒系数法进行联合毒力评价。结果显示,氟啶虫胺腈和阿维菌素在8∶1～1∶8、氟啶虫胺腈和吡虫啉1∶1、氟啶虫胺腈和高效氯氟氰菊酯在4∶1～1∶4配比范围对苹果黄蚜有增效作用,3种组合最佳增效比均为1∶1。田间应用结果显示,药后3～21 d,22%氟啶虫胺腈SC单剂对苹果黄蚜防效达94.77%～99.40%;22%氟啶虫胺腈SC分别与5%阿维菌素EC、70%吡虫啉WG和2.5%高效氯氟氰菊酯EW按有效成分1∶1混配后对苹果黄蚜防效达86.43%～97.00%,均显著高于相应单剂对照,持效期可达21 d。推荐采用氟啶虫胺腈单剂及氟啶虫胺腈与阿维菌素、吡虫啉或高效氯氟氰菊酯混配剂作为替代药剂防治苹果黄蚜。     

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。     

4种杀虫剂对玉米3种害虫的毒力及种子处理防治效果评价

为评价4种杀虫剂在玉米田防治灰飞虱Laodelphax striatellus、禾蓟马Frankliniella tenuicornis和玉米蚜Rhopalosiphum maidis的应用前景,采用浸苗法测定了其对3种害虫的毒力,并通过种子处理筛选对3种害虫田间防效较高的药剂。结果表明,噻虫嗪、呋虫胺和吡虫啉对灰飞虱、禾蓟马和玉米蚜具有较高毒力,LC50分别为0.14～1.10、4.24～31.01 mg/L和0.80～7.49 mg/L,氟啶虫酰胺的毒力最低,对3种害虫的LC50分别为84. 55、222.72 mg/L和44.81 mg/L。采用种子处理的方式施药后,各药剂处理组玉米出苗率与对照组无显著差异,安全性较高;播种后30 d,20%氟啶虫酰胺种子处理悬浮剂对灰飞虱、禾蓟马的防效均在75%以上,播种后40 d,70%噻虫嗪种子处理可分散粉剂对灰飞虱防效最高,其次为20%氟啶虫酰胺种子处理悬浮剂、8%呋虫胺悬浮种衣剂和600 g/L吡虫啉悬浮种衣剂;播种后50 d(玉米抽雄期)调查,20%氟啶虫酰胺种子处理悬浮剂对玉米蚜防治效果可达92.1%,表现出较高的防治效果,噻虫嗪、呋虫胺、吡虫啉防治效果略低,但均在70%以上,能有效防治玉米蚜的为害。综上,氟啶虫酰胺、噻虫嗪、呋虫胺和吡虫啉均适合用于防治玉米田灰飞虱、禾蓟马和玉米蚜3种害虫。     

3种新型杀虫剂对苹果黄蚜的毒力效果评价

采用浸叶法在室内测定了3种药剂对苹果黄蚜的毒力,并在田间进行了防治试验。室内毒力测定结果表明:供试3种新型药剂中,双丙环虫酯和氟吡呋喃酮对苹果黄蚜的毒力较高,LC₅₀分别为3.16 mg/L和23.58 mg/L,三氟苯嘧啶毒力较低,LC₅₀为329.92 mg/L。田间试验结果表明:3种药剂对苹果黄蚜均有较好的速效性和持效性。17%氟吡呋喃酮可溶液剂和10%三氟苯嘧啶悬浮剂各处理3～7 d防效为82.19%～93.45%,药后30 d防效达到78.91%～87.92%;50 g/L双丙环虫酯可分散液剂2.5 mg/kg和4.2 mg/kg处理药后3～7 d防效为94.64%～97.04%,药后21 d防效仍可达88%以上。因此,3种新型药剂均可以用于防治苹果黄蚜,田间使用时推荐有效成分用量为双丙环虫酯2.5～4.2 mg/kg,氟吡呋喃酮113～170 mg/kg,三氟苯嘧啶28～80 mg/kg。     

添加Silwet 408对3%阿维菌素微乳剂药液表面张力和接触角及其对两种害虫作用效果的影响

通过室内测定和田间防治试验,研究了在3%阿维菌素微乳剂中添加不同量的有机硅表面活性剂Silwet 408后,对药液的表面张力及在苹果叶片上接触角的影响,以及添加助剂后药剂对苹果红蜘蛛Panonychus ulmi和苹果绣线菊蚜Aphis citricola毒力及防效的变化。结果表明:Silwet 408能有效降低3%阿维菌素微乳剂药液的表面张力及其在苹果叶片上的接触角,且在试验添加量(质量分数)3%~10%范围内,表面张力和接触角均随助剂添加量的增加而不断降低。生物测定结果表明:添加Silwet 408可显著提高3%阿维菌素微乳剂对苹果红蜘蛛的毒力及田间防效,但对苹果绣线菊蚜的毒力和田间防效则无明显影响。研究表明,在杀虫剂中添加增效助剂以提高药效时,除了需考察该助剂能否显著降低药液的表面张力及在靶标上的接触角外,害虫种类也是需考虑的因素之一。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Plant–herbivore asynchrony necessitates augmentative releases of the exotic beetle,Zygogramma bicolorata,to enhance the biological control of P arthenium hysterophorus

Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F ₃, F ₄ and F ₅, but not in F ₁ and F ₂ that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F ₁ and F ₂ in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.