沙田柚低温杀虫处理试验研究

对人工感染桔小实蝇(Bactrocera dorsalis)的沙田柚开展低温除害处理研究.研究结果表明,在1.7℃±0.06℃和1.8℃±0.33℃的低温条件下,连续处理14天,可将感染在果实中71184头和46341头的桔小实蝇幼虫全部杀死;在0.96℃±0.25℃的低温条件下,连续处理13天,可将感染在果实中58866头桔小实蝇幼虫全部杀死.果实损伤测定试验结果表明,在1～2℃下连续贮藏14天,沙田柚果实无损害.     

桔小实蝇发育速率与温度关系的研究

本文报道了人工饲料饲养的桔小实蝇在恒温条件下发育速率与温度的关系。结果表明,桔小实蝇卵、幼虫及蛹的发育起点温度分别为１２．１９℃、５．２４℃及１０．０８℃;有效积温分别为１９．９日度、１５６．７日度及１５７．８日度。整个世代发育起点温度为１２．１９℃,完成生活史（从卵到成虫）所需的有效积温为３３４．４日度。文中还对桔小实蝇年发生世代数进行了讨论。     

Efficacy and residues of phloxine B and uranine for the suppression of Mediterranean fruit fly in coffee fields

The field efficacy of a bait containing phloxine B, uranine and Provesta 621 protein was tested against Mediterranean fruit fly (Ceratitis capitata; Medfly) by aerial and ground spraying in about 84 ha of coffee fields in Kauai, Hawaii, USA. Concurrently, soil and crop samples were collected from the aerially sprayed field and its unsprayed control field for residue studies. Efficacy of the sprays was assessed through trapping with both protein-baited and trimedlure-baited traps and through the infestation level of coffee cherries collected at least three-quarters ripe. The C capitata population was low at the start of the aerial and ground spray studies, but dramatically increased in the control fields. This increase coincided with initial ripening of coffee cherries. During times of peak population levels, C capitata populations were reduced by more than 91% in the ground-sprayed field and 99% in the aerial-sprayed field, relative to the populations in their respective control fields and based on protein-baited trap catches. Results of residue analyses indicated that uranine dissipated quickly compared with phloxine B on coffee and soil. Coffee samples collected at pre-spray periods had phloxine B residues of 7.2-25.5 ng g-1 on berries. Phloxine B concentrations were much higher on coffee leaves (163-1120 ng g-1). Lower concentrations of the dye were found from coffee samples collected during rainy days. Average phloxine B concentrations immediately after spraying were 56 and 2840 ng g-1 in coffee berries and leaves, respectively. Dissipation of phloxine B on berries was fast, with a half-life (t1/2) of 3 days. Dissipation of phloxine B on leaves was fitted to two linear phases: the initial (0-4 days) with a shorter t1/2 of 3 days and the later phase (4-28 days) with a longer t1/2 of 15 days. Average concentrations of phloxine B in the top soil ranged from 50 to 590 ng g-1 at pre-spray. Phloxine B initial concentration (770 ng g-1) reached a plateau immediately after the last spraying, but showed a steady decline over time with t1/2 of 16 days. Fast dissipation of the dyes in the field indicates that these chemicals may be environmentally compatible and therefore a promising alternative for fruit fly control.     

橘小实蝇不能在荔枝健果上成功产卵

根据在果园和室内测定，证实橘小蝇[Bactrocera dorsalis（Hendel）]不能在健康荔枝果实上成功产卵，但可在受损伤的果实上成功产卵。     

杨桃园桔小实蝇的防治指标

为有效控制桔小实蝇的危害,通过田间调查桔小实蝇数量动态和杨桃产量损失,研究了杨桃上桔小实蝇的防治指标。结果表明,杨桃产量损失率与桔小实蝇虫口密度、杨桃被害率之间具有显著相关性;建立了第一收获期至第四收获期桔小实蝇虫口密度、杨桃被害率与杨桃产量损失率回归方程。根据防治指标求解模型,将各回归方程系数和求解防治指标参数代入,得到一年四个收获期里不同产量水平下的桔小实蝇的防治指标。当以桔小实蝇虫口密度作为防治指标时,各收获期的防治指标分别为5.6、14.0、19.3和8.8头/瓶;经济允许密度为10.1、19.5、21.7和10.4头/瓶。当以杨桃被害率作为防治指标时,各收获期的防治指标分别为5.3%、8.9%、6.8%和7.5%;经济允许损失率为15.1%、15.3%、12.0%和9.8%。     

桔小实蝇热响应数学模型比较

利用恒温水浴槽对桔小实蝇的卵(16+2h)、1龄幼虫(48+2h)和非取食3龄老熟幼虫进行不同温度和时间组合的热水浸泡处理,分别利用热动力学模型、机率值模型、Logit模型和Log-Log模型对死亡率与处理时间的关系进行了分析比较,以明确最佳分析数学模型和热处理最耐受虫态。试验结果表明:热动力学模型为预测热处理致死时间的最佳数学模型;在44℃、45℃和46℃等温度条件下,桔小实蝇卵的耐热能力最强,其次为1龄幼虫,3龄幼虫耐热能力最差。该结果为利用热水浸泡处理等热处理技术对桔小实蝇进行检疫处理奠定了基础。     

基于PERT与仿真技术的橘小实蝇传入定量风险评估

检疫性害虫传入风险定量评估是外来入侵有害生物控制的重要组成部分。本文应用计划评审法(PERT)和Monte Carlo仿真技术分析了2007年春夏两季(5～8月)入穗外地水果(香蕉、芒果、番石榴)经过采摘、运输、销售、丢弃等环节后,传入广州地区的橘小实蝇的数量及其风险概率。结果表明,橘小实蝇累计传入数量为590～598头,能够形成295～372对潜在交配成虫,经典PERT模型和Monte Carlo仿真的计算结果很接近,传入风险确实存在,为100%。同时灵敏度分析显示,遭受橘小实蝇危害的水果比例、1kg受害水果所含橘小实蝇幼虫的数量、有限时间内3龄幼虫的逃逸比率是影响害虫传入数量的3个最主要的因素。     

非寄主植物提取物对橘小实蝇的产卵拒避作用

选取4种非寄主植物柠檬桉Eucalyptus citriodora、樟树Cinnamomum camphora、白千层Melaleuca leucadendron、夹竹桃Nerium indicum,初步研究了这4种植物叶子提取物对橘小实蝇Bactroceradorsalis的产卵拒避作用。以无水乙醇作溶剂,供试4种植物中的白千层提取物对橘小实蝇具有较强的产卵拒避作用。检测了橘小实蝇对4种植物的乙醇提取物的触角电位值,发现各生物测定值与雌虫触角电位值呈显著相关性,表明其中的挥发性组分是橘小实蝇对植物提取物产生拒避反应的重要原因之一。用无水乙醇、乙醚、石油醚、二氯甲烷作溶剂,分别提取白千层叶,仅乙醇提取物有显著拒避作用;用这4种溶剂分别提取樟树叶,则无水乙醇、乙醚、石油醚作溶剂的提取物都有较好效果。     

Organophosphate resistance in olive fruit fly, Bactrocera oleae, populations in Greece and Cyprus

The olive fruit fly Bactrocera oleae (Gmelin) (Diptera: Tephritidae) is the most important pest of olives in countries around the Mediterranean basin. Its control has been based mostly on bait sprays with organophosphate insecticides (usually dimethoate or fenthion) for about 40 years. In the present study, the resistance status of olive fruit fly populations to dimethoate was examined in Greece and Cyprus over 2 years. Thirty-one populations from various regions of Greece, nine from Cyprus and one laboratory susceptible strain, which served as a control, were assayed by topical application of dimethoate. Considerable variation in the resistance levels to dimethoate was recorded in the populations of B. oleae, with resistance ratios ranging from 6.3 to 64.4 (ED(50) values 12.5-128.7 ng dimethoate per insect). The highest resistance ratios were found in populations from Crete, and the lowest in those from Cyprus. This variation could be attributed to different selection pressures from insecticidal applications among populations from the various regions. Migration of resistant genotypes, either autonomous or via commerce, may also be involved.     

不同塑膜袋的防虫效果及对番石榴果实品质的影响

以不同材质和厚度的塑料薄膜为材料,研究果实套袋对橘小实蝇、番石榴实蝇的防虫效果,以及对番石榴品质的影响。室内套袋试验结果表明,当PO、PE厚度≥20μm、PP厚度≥15μm时,橘小实蝇、番石榴实蝇雌虫产卵管不能穿透塑料薄膜而产卵在果实上;田间套袋试验结果表明,PO(20μm)和PE(20μm)套袋的果实均未检测到实蝇。套袋果实外观较未套袋果实好,30μm PP套袋的番石榴果实品质与未套袋果实无显著差异,PO(20μm)、PO(25μm)、PE(20μm)和PE(30μm)套袋的番石榴果实中可溶性固形物、可滴定酸、糖含量等较对照低。     

高度和地点对性引诱剂诱集桔小实蝇雄虫效果的影响

观察研究了番石榴园桔小实蝇性引诱剂诱捕器悬挂高度和生态环境类型对诱集效果的影响。结果表明,诱捕器的悬挂高度一般应在1m以上,如果树较高,则应悬挂到不低于果树平均高度的0.5～1m;诱捕器的设置位置明显影响诱集结果,若要进行种群动态监测,诱捕器应设置在当地有代表性的果园区,且最好在果园内、果园外都设点进行诱捕。     

桔小实蝇在不同杨梅品种上的生长发育特性研究

本文选择了浙江3种不同杨梅品种,研究了桔小实蝇取食后的生长发育相关5种性状的差异,结果表明,幼虫历期以荸荠种最短,蛹历期和蛹重,水梅值最小;雄成虫东魁最重,并均与另2个杨梅品种差异达显著水平。而幼虫,幼虫-蛹,幼虫-成虫3种存活率,荸荠种最高,水梅最低,二者差异也达显著水平。显然桔小实蝇对不同杨梅品种喜好有所不同,其较为喜好荸荠种,较不喜好水梅。结合果实性状考查结果,不喜好的原因可能与水梅偏酸有关。但上述3品种上桔小实蝇生长发育性状与其嗜好寄主香蕉极为     

Feeding and attraction of non-target flies to spinosad-based fruit fly bait

A spinosad-based fruit fly bait, GF-120, has recently become a primary tool for area-wide suppression or eradication of pest tephritid fruit flies. The present study assessed the attraction and feeding of five non-target fly species to GF-120 in Hawaii. These non-target flies include three beneficial tephritid species [Eutreta xanthochaeta (Aldrich), Tetreuaresta obscuriventris (Loew), Ensina sonchi (L.)] introduced for weed biological control, an endemic Hawaiian tephritid [Trupanea dubautiae (Bryan)] (all Diptera: Tephritidae) and the cosmopolitan Drosophila melanogaster Meigen (Diptera: Drosophilidae). All five non-target fly species were susceptible to GF-120, as was the target pest Mediterranean fruit fly Ceratitis capitata (Wiedemann). Feeding on, or even brief tasting of, GF-120 killed all fly species within 2 h. When individual flies were provided with a choice of GF-120 or honey solution, there was no difference in the frequency of first food encounter by E. xanthochaeta, D. melanogaster or C. capitata. The other three non-target species approached honey more often than GF-120 in their first food encounter. Feeding times on GF-120 and honey were not significantly different for D. melanogaster and C. capitata, while the other four non-target species fed longer on honey than on GF-120. There was no significant difference in feeding time on honey versus GF-120 between males and females of each species. These results suggest that area-wide treatment using GF-120 for the purpose of eradication of pest fruit flies has potential negative impacts on these and other non-target fly species in Hawaii.     

Spinosad bait sprays against the olive fruit fly (Bactrocera oleae (Rossi)): effect on the canopy non-target arthropod fauna

Abundance and diversity of arthropods were compared in olive trees treated against the olive fruit fly with spinosad bait sprays and an untreated control, paying special attention to predators and parasitoids. Spinosad bait sprays did not reduce the abundance and diversity of arthropods as a whole in the canopy. However, principal response curve analysis revealed a significant deleterious effect of the treatments on natural enemies in the last of the three years of study. The most affected taxa were Anthocoridae (especially Orius spp.) and Aphelinidae.