A novel source of resistance to the two-spotted spider mite in Lycopersicon pimpinellifolium (Jusl.) Mill.: its genetics as affected by interplot interference

We have previously found an accession of Lycopersicon pimpinellifolium (Jusl.) Mill. (`TO-937') that appeared to resist attack by the two-spotted spider mite (Tetranychus urticae Koch). L. pimpinellifolium is a very close relative of the cultivated tomato (Lycopersicon esculentum Mill.) and thereby a potential source of desirable traits that could be introgressed to the crop species. The objective of this study was to investigate the genetics of the resistance present in `TO-937'. Resistance to infestation by the spider mite was quantified in 24-plant plots of L. pimpinellifolium accessions `TO-937' and `PE-10', L. pennellii accession `PE-45', L. esculentum cultivars `Moneymaker', `Roma' and `Kalohi' (reported to be partially resistant: Stoner & Stringfellow, 1967), and the interspecific F₁ cross, L. esculentum `Moneymaker' × L. pimpinellifolium `TO-937'. Only `TO-937', the F<sub>1</sub>, and`PE-45' were found to be resistant. Resistance of `TO-937' was complete when evaluated in two small greenhouses completely planted with `TO-937' so as to simulate the genotypic homogeneity usual in commercial crops. Generations (P₁, P₂, F₁, F₂, BC₁P₁, and BC₁P₂) of a P₁ (susceptible) × P₂ (resistant) cross (`Moneymaker' × `TO-937') were studied for resistance in a single-plant per plot design. Resistance of `TO-937' was inherited with complete dominance and appeared to be controlled by either two or four genes according to whether segregation in the F₂ or the BC₁P₁, respectively, were considered. However, calculation of the number of genes involved in the resistance was complicated by negative interplot interference due to the high frequency of resistant genotypes within most of the generations. This revised version was published online in July 2006 with corrections to the Cover Date.     

蜘蛛的几种定量采集方法

介绍了野外采集森林冠层、树干和地表层蜘蛛的冠层喷雾法、树干陷阱法和单位地表面积法,分别阐述了每种方法的特点及使用时的注意事项,并探讨了3种采集方法在生物多样性研究及保护中的应用前景。     

Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers （ Ostrinia fumaeafis） and Spiders （Xysticus ephippiatus）

Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer （ACB） larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore, randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin＇s efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application.     

朱砂叶螨危害对豇豆幼苗叶绿素和蛋白质含量的影响

豇豆幼苗叶片受朱砂叶螨危害0～8 d内,叶绿素、蛋白质含量及组成随危害程度的加深均有不同程度的变化。在试验期内,受害叶片蛋白质含量随危害时间的延长稳定增加,与危害时间之间差异显著(P<0.05),在危害8 d时,两虫口密度之间也产生显著差异(P<0.05);在危害4 d后,受害叶片产生带8、9两条蛋白质谱带,且含量随危害时间的延长而增加;在实验期内,两处理叶片叶绿素a、叶绿素b及叶绿素总量均随危害时间的延长而下降,不同危害时间之间下降的幅度差异显著(P<0.05),另外,相同危害时间下两处理叶片叶绿素a、叶绿素b及叶绿素总量下降的幅度也随虫口密度的增大而增加,两虫口密度之间差异显著(P<0.05)。     

草间小黑蛛对褐稻虱的捕食作用及其模拟模型

在大试管内研究了草间小黑蛛对褐稻虱的捕食反应,测定了褐稻虱虫龄及温度对功能反应的影响,并建立了同时考虑这2个因子影响的 Holling 圆盘方程.还研究捕食者个体间的相互干扰反应,并建立草间小黑蛛对猎物密度和自身密度的共同反应模型.     

苹果红蜘蛛药效试验研究

为了使果树正常生长发育,获得高产优质的果品,1986～1988年,我们在景泰条山农场设点,对苹果红蜘蛛的防治进行了大量的调查研究。根据苹果红蜘蛛的越冬螨口密度、该场用药历史,选用粘土柴油乳剂、石硫合剂、柴油乳剂等多种药物喷杀越冬卵,以常规防治为对照,筛选出具有杀虫效果好,不产生抗药性,对人畜安全,又不污染环境,成本低等优点的粘土柴油乳剂和石硫合剂为较理想的药物。两年来,该场800余亩果树,均用粘土柴油乳剂喷布,枝干上每平方厘米卵的粒数由原来的303.8粒下降到1.7～21.8粒,基本控制了该虫的发生发展和为害。     

果园越冬叶螨群落和种间关系

1989年对甘肃武威果园(N38°，E103°)越冬叶螨的群落调查表明：该区果园越冬叶螨有4种：李始叶螨Eotetranychus pruni (Oudemans)、山楂叶螨Tetranychus viennensis Zacher、苹果全爪螨Panonychus ulmi Koch 和果苔螨Bryobia rubrioculus (Scheuten)。发现在不同的越冬寄主上以株为单位时其群落内种的组成和种间关系不同。聚类分析表明，杏园和梨园在叶螨群落组成上的相似性较高，而与苹果园叶螨群落的差异较大。调查发现，4种叶螨在田间自然条件下以单个种、两个种形成的群落为主，3个种组成的群落少，但没有4个种形成的群落（以株为单位）。2×2列联表法分析表明，群落中两个种的种间关系在不同的果园表现不同。分析发现叶螨群落及种间关系的研究对叶螨的综合防治有重要意义。     

Spider Mite Detection and Canopy Component Mapping in Cotton Using Hyperspectral Imagery and Spectral Mixture Analysis

Spectral mixture analysis and hyperspectral remote sensing are analytical and hardware tools new to precision agriculture. They can allow detection and identification of various crop stresses and other plant and canopy characteristics through analysis of their spectral signatures. One stressor in cotton, the strawberry spider mite (Tetranychus turkestani U.N.), feeds on plants causing leaf puckering and reddish discoloration in early stages of infestation and leaf drop later. To determine the feasibility of detecting the damage caused by this pest at the field level, AVIRIS imagery was collected from USDA-ARS cotton research fields at Shafter, CA on 4 dates in 1999. Additionally, cotton plants and soil were imaged in situ in 10 nm increments from 450 to 1050 nm with a liquid-crystal tunable-filter camera system. Mite-damaged areas on leaves, healthy leaves, tilled shaded soil, and tilled sunlit soil were chosen as reference endmembers and used in a constrained linear spectral mixture analysis to unmix the AVIRIS data producing fractional abundance maps. The procedure successfully distinguished between adjacent mite-free and mite-infested cotton fields although shading due to sun angle differences between dates was a complicating factor. The resulting healthy plant, soil, mite-damaged, and shade fraction maps showed the distribution and relative abundance of these endmembers in the fields. These hardware and software technologies can identify the location, spatial extent, and severity of crop stresses for use in precision agriculture.     

Ecological Characteristics of Dominant spiders in the Rice Fields of Hunan Province

总结近年来对湖南省境内不同地理、生态类型的稻田蜘蛛群落结构的研究结果,发现主要优势种为拟水狼蛛(Piratasubpiraticus),锥腹肖蛸(Tetragnathamaxillosa),食虫沟瘤蛛(Ummeliatainsecticeps),八斑鞘腹蛛(Coleosomaoctomaculata)和拟环纹豹蛛(Pardosapseudoannulata)等五种蜘蛛,并对这些优势种蜘蛛的生态特点进行了初步分析。     

Effect of high-pressure hot-water washing treatment on fruit quality, insects, and disease in apples and pears: Part III. Use of silicone-based materials and mechanical methods to eliminate surface pests

Surface arthropods on pome fruits can cause export problems and disrupt commercial markets. Eliminating insects and mites on the packing line would be the last opportunity to provide for pest-free produce. In this study, an experimental packing line was used to evaluate techniques using different surfactant baths, pressurized water sprays, and styles of rotating brushes to remove field-collected and laboratory-reared grape mealybug, Pseudococcus maritimus (Ehrhorn) (Homoptera: Pseudococcidae), the diapausing two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and the woolly apple aphid, Eriosoma lanigerum (Hausman) (Homoptera: Aphididae). The organosilicone Silwet L-77 was no more effective than a silicone-based food grade defoamer in aiding removal. Mechanical methods, such as the style of rotating brushes and pressurized sprays, were significantly effective in removing surface arthropods. No improvement in removal occurred when pressure was increased beyond 420 kPa. These techniques can be easily adapted to commercial facilities and will reduce the incidence of surface arthropods on marketed fresh fruits.