Field trial on the effects of the herbicide MCPA on ixodid ticks

Abstract

Studies were conducted to develop a pheromone‐trap monitoring system for the sweet potato weevil, Cylas formicarius (Fabricius), in sweet potato, Ipomoea batatas (L.) Lam., fields in four states: Florida, Louisiana, North Carolina, and Texas. The present studies examined the attractiveness of sex pheromone synthesized by two sources (USDA and AgriSense) and pheromone of different purities (75–99%) to weevils in the field. In all but one trial, weevil counts did not differ between traps baited with pheromone from the two sources for each of two doses (10 and 100 μg). Percentages of weevils caught per replicate per sample date were not consistently positively correlated with purity (significant in four of 10 trials); however, slope estimates were steeper in regions with lower trap counts (North Carolina and Louisiana) than in those with higher trap counts (Florida). Because the pheromone will be used to monitor weevils In both weevil‐free and weevil‐infested regions, the use of pheromone with a purity level >99% is most appropriate. The importance of these data in pheromone‐trap monitoring programmes for this weevil worldwide is discussed.     

桃蛀螟研究的历史、现状与展望

本文就国内外对桃蛀螟[Conogethes puncti feralis(Guene)]的研究历史与现状进行了综述,涉及桃蛀螟的生物学和生态学特性、性信息素组成、交尾行为、分类学、人工饲养及综合防治技术等方面。提出了今后有待进一步深入研究的问题。     

Attract‐and‐kill: a new strategy for the management of the potato tuber moths Phthorimaea operculella (Zeller) and Symmetrischema tangolias (Gyen) in potato: laboratory experiments towards optimising pheromone and insecticide concentration

BACKGROUND: Sex pheromones of the potato tuber moths Phthorimaea operculella (Zeller) and Symmetrischema tangolias (Gyen) are ideal tools to monitor pest flight activity but are not used as means of control. The aim of the present study was to test the suitability of an attract‐and‐kill strategy consisting of pure pheromones and the contact insecticide cyfluthrin as the active ingredient, formulated with plant oils and ultraviolet absorbers, and applied in droplet sizes of 100 µL. RESULTS: Cyfluthrin at a concentration of 5 g L^?1 resulted in the highest and fastest killing of males after 48 h, with a 100% mortality after 3–4 days. In contrast, control males survived for 13 days. In olfactometer experiments, the pheromone concentration of 0.5 g L^?1 was significantly most attractive against eight virgin females. At controlled conditions (20 °C), no reduction in efficacy of the attract‐and‐kill formulation was observed for a minimum period of 36 days, whereas under natural environmental conditions the efficacy reduced gradually after day 6 of exposure. The longer the droplet was exposed, the longer was the time to reach 100% mortality of males. CONCLUSIONS: Compared with attract‐and‐kill studies for other pest species, the results are promising as a means of achieving highly effective control of potato tuber moths under field conditions. Copyright © 2010 Society of Chemical Industry     

Optimizing aphid biocontrol with the predator Aphidoletes aphidimyza,based on biology and ecology

Aphidoletes aphidimyza is one of the most important predators used in the augmentative biological control of aphids, key pests of many crops worldwide. Adult females are very efficient in locating aphid infestations over a relatively long range, up to 45 m, and deposit eggs near or within aphid colonies. The predatory larvae are aphid generalists preying on several agriculturally important aphid species. The successful use of this biocontrol agent in agricultural systems depends on several biotic and abiotic factors. Among biotic factors, aphid species, plant structure, interspecific competition and intraguild predation may significantly impact the predator´s population dynamics. Key abiotic conditions include day lengths (above a critical threshold to prevent diapause), availability of mating sites in the crop, temperature (above 15 °C to enable egg laying), air relative humidity (above 70%) and availability of pupation sites. Although several successes have been reported in open field crops with naturally occurring or released populations, commercial releases are primarily used in protected crops. Optimized emergence boxes combining provisioning of food sources for the adults, integration with the technological advances that occurred in the greenhouse environment lately, insights into the nutritional ecology in open field crops and exploration of the genetic variability are proposed as future directions to improve adoption and efficacy of A. aphidimyza in crop protection. © 2018 Society of Chemical Industry     

Evaluation of attract-and-kill strategy for management of cocoa pod borer,Conopomorpha cramerella,in Malaysia cocoa plantation

Abstract

In South-East Asia, cocoa production is dramatically affected by cocoa pod borer (CPB) infestations. As an alternative tool to chemical control, the efficacy of attract-and-kill strategy (CPB sex-pheromone as attractant and Delta trap without sticky liner sprayed with cypermethrin solution as killing station) was evaluated and compared with current standard CPB management approach as control treatment during two main cocoa harvest seasons in Malaysia (with 100 µg and 33.3 µg CPB-pheromone loading per station, respectively). In both seasons, attract-and-kill strategy was highly effective at reducing male flight activity (p?<?0.05) in attract-and-kill plots comparing with standard CPB management plots. For the percentage of CPB-infested pods, the attract-and-kill strategy (100 µg) was as good as the conventional pesticide spray applications of cypermethrin (p?=?0.083) in first season. However, it was significantly (p?=?0.021) reduced in the second season with lower pheromone loading (33.3 µg), indicating that this semiochemical based strategy is far superior to and more feasible than the currently applied conventional synthetic pesticide treatment and is therefore a good alternative in CPB integrated pest management.     

Effects of application rate and interval on the efficacy of sprayable pheromone for mating disruption of the oriental fruit mothGrapholita molesta

The efficacy of microencapsulated sprayable pheromone was evaluated at different application rates and intervals for mating disruption of the oriental fruit moth,Grapholita molesta (Busck), in apple orchards during 2002. The following treatments were arranged in a randomized complete block design with three replications: (i) a low rate of pheromone (6.2 g a.i. ha⁻¹) applied at 14-day intervals, (ii) a medium rate of pheromone (12.4 g a.i. ha⁻¹) applied at 28-day intervals, (iii) a high rate of pheromone (24.7 g a.i. ha⁻¹) applied at 28- day intervals, and (iv) a non-pheromone control (insecticides only). The combination of a single insecticide application against first generationG. molesta at petal fall with one pheromone application each for the second, third and fourth generations at 12.4–24.7 g a.i. ha⁻¹ successfully controlled low populations. Pheromone-treated blocks. had significantly lower trap catches than those in the insecticide-treated control blocks. Among pheromone treatments, significantly more moths were caught in the 6.2 g compared with the 12.4 and 24.7 g rates. Fruit damage was <1% at harvest and there were no significant differences among treatments. Low rate frequent applications of sprayable formulation appeared to be effective under low pest pressure but efficacy declined with increasing populations. Further studies are needed to demonstrate the effectiveness of this approach under higher pest pressure. http://www.phytoparasitica.org posting July 13, 2005.     

Field models for the prediction of leaf infection and latent period of Fusicladium oleagineum on olive based on rain,temperature and relative humidity

Although much is known about the effect of climatic conditions on the development of peacock leaf spot of olive, field‐operational models predicting disease outbreaks are lacking. With the aim of developing such models, a 10‐year survey was conducted to relate leaf infection to climate parameters that can be easily monitored in the field. As outbreaks of disease are known to be linked to rain, models were evaluated for their ability to predict whether infection would occur following a rain event, depending on air temperature and duration of relative humidity above 85%. A total of 134 rain events followed by confirmed leaf infection and 191 rain events not followed by detectable infection were examined. The field data were adequately fitted (both specificity and sensitivity >0·97) with either a multilayer neural network or with two of six tested regression models describing high boundary values of high humidity duration, above which no infection occurred over the temperature range, and low boundary values below which no infection occurred. The data also allowed the selection of a model successfully relating the duration of latent period (time between infection and the first detection of leaf spots) as a function of air temperature after the beginning of rain (R² > 0·98). The predictive abilities of these models were confirmed during 2 years of testing in commercial olive orchards in southern France. They should thus provide useful forecasting tools for the rational application of treatments and foster a reduction in fungicide use against this major disease of olive.     

The efficacy of spinosad against the western flower thrips, Frankliniella occidentalis, and its impact on associated biological control agents on greenhouse cucumbers in southern Ontario

Insecticides are the most commonly used tactic to control western flower thrips (WFT), Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), on greenhouse cucumber. However, WFT has developed resistance to several of the insecticides presently in use. In addition, some of these insecticides adversely affect greenhouse biological control agents used to control WFT, resulting in subsequent pest resurgence. Therefore, there is a need to identify novel insecticides with unique modes of action for use in integrated pest management (IPM) programs to effectively control WFT with minimal impact on associated biological control agents. In laboratory bioassays conducted in 2001, immature and adult WFT and three associated greenhouse biological control agents: Amblyseius cucumeris Oudemans (Acarina: Phytoseiidae), Orius insidiosus Say (Hemiptera: Anthocoridae) and Encarsia formosa Gahan (Hymenoptera: Aphelinidae) were exposed to direct, direct/residual, and residual contact applications of the novel biopesticide, spinosad (Conserve 120 SC), and the industry standard for whitefly control, endosulfan (Thiodan 50 WP). In all three types of assay, spinosad was effective against immature and adult WFT life stages. It showed low toxicity to A. cucumeris, moderate toxicity to O. insidiosus and high toxicity to E formosa. Greenhouse studies involving exposure of immature and adult WFT and adult biological control agents to cucumber leaves sprayed previously with spinosad supported the laboratory data. Spinosad showed low toxicity to A. cucumeris exposed to leaves 1 day after treatment (DAT), moderate toxicity to O. insidiosus 1 and 8 DAT, and high toxicity to E. formosa up to 28 DAT. These data, along with spinosad's unique mode of action, suggest it would be a valuable reduced-risk control agent for greenhouse cucumber IPM programs.     

陕西渭北苹果病虫害综合治理政策和研究的建议

通过对陕西省渭北苹果生产现状的调查和了解,作者提出了几项建议和意见：（1）鲜果出口需要一套复杂的病虫害管理体系,包括植物检疫、有害生物综合治理体系及苹果生产过程中的透明度等;（2）要鼓励和支持进行当地研究;（3）培训果农,加强技术推广,改善果园管理,鼓励国家和地区资助项目间充分合作;（4）单一的销售体系是很值得考虑的,也就是说,所有的果品都由一个机构经销出售,这个组织是唯一由法律允许进行苹果、梨出口经营的公司,果农推举代表民主经营,经费来源于果农自己;（5）尽快调查不合法、未注册的农药销售及生产情况,并对这种行为进行严厉惩罚;（6）苹果黑星病或许将会成为该地区的一个严重问题,需要优先考虑;（7）几种病虫害的发生问题越来越严重,需要研究其原因及对策。