黄土高原雨养区不同种植年限紫花苜蓿土壤真菌群落的分布特征

依托布设在黄土高原雨养农业区的长期田间定位试验,以玉米田为对照、不同种植年限紫花苜蓿地(L2003,L2005,L2012)土壤为研究对象,采用真菌ITS高通量测序技术探究不同种植年限苜蓿土壤真菌群落分布与演替特征,为黄土高原苜蓿人工草地的可持续利用提供微生物参数。结果表明:黄绵土共检测到真菌6门24纲73目156科313属,主要包括子囊菌门(Ascomycota)、接合菌门(Zygomycota)、担子菌门(Basidiomycota)。苜蓿土壤和农田土壤真菌群落结构差异显著,随苜蓿种植年限延长子囊菌门相对丰度先降低后升高,接合菌门和担子菌门相对丰度先升高后降低,表现为L2003子囊菌门相对丰度显著高于L2005处理12.42%(P0.05),接合菌门相对丰度显著低于L2005处理153.54%(P0.05)。农田土壤优势属为被孢霉属(Mortierella)、绿僵菌属(Metarhizium)和腐质霉属(Humicola),苜蓿土壤共有优势真菌属为刺孢属(Phaeomycocentrospora)、白僵菌属(Beauveria)和被孢霉属。农田土壤被孢霉属相对丰度显著高于苜蓿土壤62.38%～73.48%(P0.05),随着苜蓿种植年限的延长,土壤促生菌(白僵菌属和绿僵菌属)丰度下降,部分病原菌(镰刀菌属、赤霉菌属)丰度增加。主成分分析发现,丛赤壳属(Nectria)、土赤壳属(Ilyonectria)和镰刀菌属(Fusarium)与第一主成分(PC1)具有较高的相关性,Lectera菌属、支顶孢属(Acremonium)和赤霉菌属(Gibberella)与第二主成分具有较高相关性,与第一、第二主成分相关性较高的菌属均为植物病原菌。     

玉米矮化病株及其根际土壤内线虫的分离与分子鉴定

为探究玉米矮化病的病原,采用Ludox TM悬浮法对从吉林和辽宁采集的玉米矮化病株及其根际土壤和健康株根际土壤分离的线虫进行了鉴定和种群比较,并对矮化病株茎基组织PCR产物进行测序分析。结果表明:玉米健康株根际土壤分离出29属线虫,特有线虫是角咽线虫属Actinolaimus和木盾移线虫属Peltamigratus,矮化玉米病株根际土壤分离出28属线虫,特有线虫为锥线虫属Dolichorus,二者相同的线虫属有27个。矮化玉米病株根际土壤中植物线虫种类和数量明显比健康株根际土壤中高,线虫种群数量差异明显的主要是矮化线虫属Tylenchorhynchus、短体线虫属Pratylenchus和刺线虫属Belonolaimus,病株根际土壤中这3个属线虫总数约占病株土壤分离线虫总数的20.23%、11.27%和10.40%。玉米矮化病株茎基组织中短体线虫属和矮化线虫属数量占优势,2个属的线虫数量分别占测序总数的22%、14%(吉林长岭)和16%、20%(辽宁黑山)。表明玉米矮化病的发生与植物线虫相关,很可能是多种线虫共同引起的病害。     

Characterization of bacterial isolates from rotting potato tuber tissue showing antagonism to Dickeya sp. biovar 3 in vitro and in planta

Possibilities for biocontrol of biovar 3 Dickeya sp. in potato were investigated, using bacteria from rotting potato tissue isolated by dilution plating on nonselective agar media. In a plate assay, 649 isolates were screened for antibiosis against Dickeya sp. IPO2222 and for the production of siderophores. Forty‐one isolates (6·4%) produced antibiotics and 112 isolates (17·3%) produced siderophores. A selection of 41 antibiotic‐producing isolates and 41 siderophore‐producing isolates were tested in a potato slice assay for control of the Dickeya sp. Isolates able to reduce rotting of potato tuber tissue by at least 50% of the control were selected. Isolates were characterized by 16S rDNA analysis as Bacillus, Pseudomonas, Rhodococcus, Serratia, Obesumbacterium and Lysinibacillus genera. Twenty‐three isolates belonging to different species and genera, 13 producing antibiotics and 10 producing siderophores, were further characterized by testing acyl‐homoserine lactone (AHL) production, quorum quenching, motility, biosurfactant production, growth at low (4·0) and high (10·0) pH, growth at 10°C under aerobic and anaerobic conditions and auxin production. In replicated greenhouse experiments, four selected antagonists based on the in vitro tests were tested in planta using wounded or intact minitubers of cv. Kondor subsequently inoculated by vacuum infiltration with an antagonist and a GFP (green fluorescent protein)‐tagged biovar 3 Dickeya sp. strain. A potato endophyte A30, characterized as S. plymuthica, protected potato plants by reducing blackleg development by 100% and colonization of stems by Dickeya sp. by 97%. The potential use of S. plymuthica A30 for the biocontrol of Dickeya sp. is discussed.     

Biological control of botrytis bunch rot in organic wine grapes with the yeast antagonist Candida sake CPA‐1

The aim of this research was to confirm the efficacy of the yeast antagonist Candida sake CPA‐1 in suppressing botrytis bunch rot development, in an organic vineyard under Mediterranean conditions for two seasons, and compare its performance with that of two biologically based products currently registered for botrytis bunch rot control in New Zealand. In 2009, treatments applied were: commercial formulations of Ulocladium oudemansii (BOTRY‐Zen^®) and chitosan (ARMOUR‐Zen^®), C. sake CPA‐1 combined with the fatty acid‐based additive Fungicover^® and combinations of these products. All treatments were applied six times between early flowering and harvest and compared with an unsprayed control. In 2010, the treatments focused on C. sake and Fungicover and the number of applications was reduced from six to four. The population dynamics of U. oudemansii and C. sake were measured and wine quality tests were carried out in both seasons. Disease control achieved by C. sake treatments in 2009 were comparable to those achieved by BOTRY‐Zen and ARMOUR‐Zen. Applications of C. sake plus Fungicover between flowering and harvest significantly (P < 0·05) reduced botrytis bunch rot incidence and severity by 64% and 90%, respectively, compared with the untreated control in 2009, and by 67% and 89%, respectively, in 2010. Treatments did not adversely affect wine quality parameters after treated grapes were processed. Candida sake consistently provided effective control of botrytis bunch rot in grapes under different meteorological and disease pressure conditions, thereby improving its potential for future commercial applications.     

RETRACTED ARTICLE: Effect of calcium chloride on the biocontrol efficacy of two antagonistic yeasts against <Emphasis Type="Italic">Penicillium expansum</Emphasis> on apple fruit

Two antagonistic yeasts, Candida membranaefaciens and Pichia guilliermondii, were evaluated for the control of the blue mold of apple caused by Penicillium expansum. Dual culture, cell-free metabolite and volatile tests were used for in vitro assay. Yeast strains of two genera inhibited growth of P. expansum; inhibition varied from 30.27% to 44.19% in dual culture, from 79.40% to 90.57% in the volatile metabolite test, and from 72.99% to 88.77% in the cell-free metabolite test. Calcium chloride (2% w/v) significantly inhibited the growth of the pathogen P. expansum, but did not affect the colony-forming units (CFU) of the yeasts C. membranaefaciens and P. guilliermondii in potato dextrose broth. The concentration of yeast suspension influenced spore germination and germ tube growth of P. expansum in vitro, as well as disease incidence and lesion development in fruits. There were significant negative relationships between the suspension concentrations of the yeasts and the growth as well as infectivity of the pathogen. The addition of calcium resulted in lower spore germination rates and slower growth of germ tubes in vitro, as well as in lower disease incidences and smaller lesion diameters compared with treatments with yeast antagonists alone. When yeast cell suspensions reached a concentration of 10⁷ CFU ml^-1, growth of the pathogen was completely limited in vitro, and no infection was found in apple fruits treated with or without calcium. This article has been retracted because part of the data shown has already been published before, by different authors. An erratum to this article can be found at     

Native and exotic coniferous species in Europe – possible host plants for the potentially invasive Siberian moth,Dendrolimus sibiricus1 Tschtv. (Lepidoptera,Lasiocampidae)

The performance of young larvae of the potentially invasive Siberian moth Dendrolimus sibiricus Tschtv. has been studied for the first time on the native and exotic coniferous species which are widely distributed and of considerable commercial value in Europe. Picea, Abies, the introduced Pinus species (five‐needle pine only), and species from the exotic genera Pseudotsuga and Cedrus (all Pinaceae) are found to be suitable hosts for pest development. Two‐needle pines and species from non‐native Tsuga (also Pinaceae) are poor hosts in terms of larval performance though they may support growth of neonates (most sensitive to food quality). Coniferous species from other families: Taxaceae and Cupressaceae are inedible for the pest. The fact that the Siberian moth is able to survive and develop on all the tested genera of Pinaceae and that some of them constitute two thirds of the European forests underline how harmful this defoliator could be in the case of its introduction into European countries.     

Plant parasitic nematodes associated with olive1

Over 70 species, belonging to 33 genera, of plant parasitic nematodes have been reported in association with olive. Several species of Helicotylenchus have been observed to cause root necrosis and considered capable of affecting olive tree growth. Three species of Meloidogyne (M. incognita, M. lusitanica and M. javanica) were responsible for heavy galling and growth retardation in inoculation trials and natural infestation. Pratylenchus vulnus has been demonstrated in inoculation trials as a potential pathogen of olive. Xiphinema species commonly occur around olive roots and X. elongatum has been shown to affect olive plant growth. Several sedentary plant nematodes attack olive. Tylenchulus semipenetrans infects olive in California (US) and Italy. Trophotylenchulus saltensis was described from olive roots in Jordan and a cyst nematode, Heterodera mediterranea, was shown to feed and multiply on olive roots. The cortical feeding cells of roots fed upon by Gracilacus peratica showed thickened and lignified wall near the penetration points of the stylet and those exposed to Ogma rhombosquamatum also presented hypertrophic nuclei and nucleoli. Rotylenchulus macrodoratus induces the formation of an enlarged mononucleate stelar or cortical ‘nurse cell’ with dense cytoplasm and hypertrophic nucleolus.     

刺五加根际效应和土壤环境因子对土壤跳虫群落结构的影响

为明确刺五加根际效应和土壤环境因子对土壤跳虫的影响,于2019年6-8月在中国科学院辽河源农业生态研究与示范基地调查刺五加根际和非根际土壤的跳虫总属数、个体数、功能性状参数以及群落特征参数,同时利用Pearson分析法和冗余分析法研究刺五加根系分泌物和土壤环境因子对跳虫群落结构的影响。结果表明,6-8月在根际土壤中捕获棘?属跳虫176头,所占比例为34.37%,为优势属,捕获钩圆?属、球角?属、长脚?属、德?属跳虫分别为26、37、32和31头,所占比例分别为5.08%、7.23%、6.25%和6.05%,均为常见属;在非根际土壤中,捕获棘?属跳虫91头,所占比例为17.77%,为优势属,捕获钩圆?属、球角?属、长脚?属、德?属跳虫分别为28、33、19和39头,所占比例分别为5.47%、6.45%、3.71%和7.62%,均为常见属;6月,刺五加根际土壤的跳虫总属数、个体数、Pielou均匀度指数分别为3.50、14.92和0.72,非根际土壤的跳虫总属数、个体数、Pielou均匀度指数分别为2.83、8.83和0.87,与根际土壤的差异显著;根际土壤跳虫的体宽、体长、触角与体长的比值、栖息环境功能性状值分别为0.73 mm、4.4 mm、0.19和0.18,显著低于非根际土壤跳虫的0.79 mm、5.58 mm、0.32和0.40;根际土壤pH与土壤跳虫群落的总属数、个体数呈正相关,与Pielou均匀度指数呈负相关,非根际土壤pH与土壤跳虫的个体数呈正相关;德?属、球角?属跳虫与土壤丁香酸含量、水杨酸含量、没食子酸含量呈负相关,长?属跳虫与土壤丁香酸含量、水杨酸含量和没食子酸含量呈正相关,棘?属和钩圆?属跳虫与土壤丁香酸含量呈负相关。表明土壤环境因子和刺五加根际效应对土壤跳虫群落有影响。     

Note: Survey of seedborne fungi of sudanese cultivars of onion,with new records

Through incubation of onion (Allium cepa L.) seed samples on potato dextrose agar and moist filter papers at 28±2°C, 32 species and four varieties belonging to 19 genera of fungi were determined as seedborne in this crop. Among them, 23 species are new reports to the mycoflora of onion seeds.Aspergillus (11 species and three varieties, ∼42.1% of the total colony count of fungi) was the most prevalent genus:A. niger (∼19.7%) was found at the highest rate in the seeds, followed byA. parasiticus (∼17.3%,A. oryzae (∼17.3%) andA. flavus (∼14.5%). The genusAspergillus was followed byPenicillium (∼12.4%),Sclerotium (∼7.1%),Fennellia, Rhizopus, Chaetomium, Drechslera andAlternaria (∼12.4%),Fusarium, Emericella andByssochlamys (∼7.1%), whereas the remaining eight genera displayed a low level of infection (∼10%). Twenty-seven species, three varieties and 12 genera represent Hyphomycetes; four genera, three species and one variety — Ascomycotina; one genus and one species — Zygomycotina; two genera and two species — other Deuteromycotina; and one genus — Oomycetes. Some species, which are known to cause devastating pre- and postharvest diseases to onion crops, were recovered from the seeds of this crop, suggesting the high possibility of their transmission by seed. http://www.phytoparasitica.org posting July 14, 2004.     

新疆盐碱地区盐爪爪内生菌群落组成与分布格局研究

为揭示盐碱环境下盐爪爪内生菌群落结构组成及其多样性，以新疆5个典型盐碱地区的盐爪爪为研究对象，采用高通量测序技术分别对其根部和地上部分样品的内生菌进行分析。结果表明：获得的366个细菌操作分类单元(Operational taxonomic units, OTUs)共涉及16个门，70个目，321个属；以变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)为主要菌门。获得的869个真菌OTUs共涉及14个门，86个目，291个属；以子囊菌门(Ascomycota)、担子菌门(Basidiomycota)、油壶菌门(Olpidiomycota)为主要菌门。其中，嗜盐单胞菌属(Halomonas)和链格孢属(Alternaria)占绝对优势。不同地区和不同组织的内生细菌群落和内生真菌群落组成及群落丰富度差异显著。土壤中的钠离子(Na⁺)、氯离子(Cl^-)和电导率(EC)与内生菌主要门的分布呈显著正相关关系，表明不同地区内生群落的构成差异主要与土壤盐碱化相关。研究初步揭示了新疆盐碱地区...     

云南省不同海拔区草地贪夜蛾幼虫肠道与粪便细菌多样性

为探明草地贪夜蛾Spodoptera frugiperda不同海拔种群的幼虫肠道及粪便细菌组成,采用分离培养法、形态特征及16S rDNA测序分析法对云南省5个海拔22个草地贪夜蛾种群的幼虫肠道及粪便细菌进行分离培养、鉴定。结果表明,从不同海拔种群的幼虫肠道和粪便中分别获得可培养细菌4门15科22属45种和4门13科18属36种,优势菌门均为变形菌门和厚壁菌门。不同海拔种群的幼虫肠道和粪便细菌组成均不同,500 m以下、1 001～1 500 m、1 501～2 000 m和2 000 m以上4个海拔种群的幼虫肠道细菌优势属和优势种分别为肠球菌属Enterococcus和铅黄肠球菌Enterococcus casseliflavus,500～1 000 m海拔种群的优势属和优势种分别为克雷伯氏菌属Klebsiella和变栖克雷伯氏菌Klebsiella variicola;500 m以下、500～1 000 m、1 001 m以上海拔种群的幼虫粪便细菌优势属分别为假单胞菌属Pseudomonas、克雷伯氏菌属和肠球菌属,优势种分别为韩国假单胞菌Pseudomonas koreensis...     

干旱区不同品种苹果树叶片内生真菌群落组成和功能特征

分析新疆典型干旱区轮台国家果树资源圃不同品种苹果树叶片内生真菌的分布特征及差异,为病害防治、品种选育和筛选功能微生物菌株提供参考。利用ITS基因高通量测序技术对6个品种苹果树叶片内生真菌进行测序,并比较其群落组成和功能特性。研究表明,苹果树叶片蕴含着丰富多样的内生真菌资源,共检测到真菌序列566453条,鉴定到5个门、15个纲、30个目、42个科及43个属。不同品种间内生真菌群落多样性存在一定差异,野苹果叶片内生真菌的多样性指数和丰度指数均较高。在门水平上的优势真菌菌群为子囊菌门(85.22%～98.68%),不同品种间差异不大。在纲和属上不同品种间有一定的差异,子囊菌门中的锤舌菌纲和座囊菌纲为优势纲,相对丰度分别在17.48%～69.69%和28.21%～67.59%之间;可归类的优势真菌属包括小粉孢属(17.47%～69.68%)、链格孢属(13.36%～39.35%)、枝孢霉属(2.94%～8.80%)和隐球菌属(0.20%～2.36%)。不同品种苹果树叶片真菌共有属的OTU数有42个,占各样品相对丰度的99%以上,而独有属的丰度各品种均低于1%。由于长期适应干旱区环境,在属水平...     

Electrophoretic and serological comparisons of pathogenesis-related (b) proteins from different plant species

Preparations of pathogenesis-related (b) proteins (PRs) from differentNicotiana species, tomato,Gynura aurantiaca, bean, and cowpea were compared to each other and to bean chitinase and a constitutive apple agglutinin by electrophoresis in polyacrylamide gels both in the absence and in the presence of SDS, and by serological double diffusion analysis using antisera against tobacco PRs and bean chitinase. PRs from different plant genera displayed a similar but not identical range of relative mobilities in both native and SDS gels, whereas bean chitinase and apple agglutinin were clearly different. None of the antisera reacted with any of the PR preparations from plant genera other than the one from which the antigen(s) had been derived. Whilst PRs within the genusNicotiana are serologically related and can be identical, PRs from different plant genera seem to be sufficiently different to be considered as genus-specific.     

Influence of native endophytic bacteria on the growth and bacterial crown rot tolerance of papaya (Carica papaya)

The native plant microbiome is composed of diverse microbial communities that influence overall plant health, with some species known to promote plant growth and pathogen resistance. Here, we show the antibacterial and growth promoting activities of autoclaved culture metabolites (ACM) from native endophytic bacteria (NEB). These NEB were isolated from a papaya cultivar (var. Cariflora) that is tolerant to bacterial crown rot (BCR) caused by Erwinia mallotivora. In this cultivar, bacterial colonization in tissues recovering from the disease was observed before onset of tissue regeneration or ‘regrowth’. We further isolated and characterized these bacteria and were able to identify two culturable stem NEB related to plant endophytic genera Kosakonia sp. (ex. Enterobacter sp., isolate EBW), and to Sphingomonas sp. (isolate EBY). We also identified root NEB under genus Bacillus (isolates BN, BS, and BT). Inhibition assays indicated that ACM from these NEB promptly (within 18-30 h) and efficiently inhibited (60–65% reduction) E. mallotivora proliferation in vitro. When surface-sterilized papaya seeds were soaked in ACM from isolates EBY and EBW, germination was variably retarded (20–60% reduction) depending on plant genotype, but plant biomass accumulation was significantly stimulated, at around two-fold increase. Moreover, greenhouse experiments show that ACM from all isolates, especially isolate EBW, significantly reduced BCR incidence and severity in a susceptible genotype (var. Solo), at around two-fold. In general, our observations of pathogen antagonism and plant growth promotion leading to disease reduction, suggested the influence of native endophytic bacteria to increased fitness in plants, and tolerance against the re-emerging crown rot disease of papaya.

     

Natural occurrence of citrinin in rice grains and its biocontrol byTrichoderma hamatum

Paddy rice was sampled from El-Sharkia, El-Gharbia, El-Dakahlia and Kafr El-Shekh governorates, Egypt. Of the 30 samples taken, ten were contaminated with the mycotoxin citrinin. An average of 6.79 × 10⁴ fungal spores per gram rice was found. The isolated fungi represented 47 species and 28 genera. The predominant genera wereAspergillus, Cladosporium andPenicillium. Aspergilli were represented by 22 species;Aspergillus niger andA. flavus had the highest occurrence.Penicillium viridicatum produced the highest amount of citrinin on glucose ammonium nitrate salts broth and rice grains, and hence this isolate was selected as a good producer of citrinin in this study. The presence ofTrichoderma hamatum reduced the amount of citrinin produced byP. viridicatum compared with its respective control. The excessive growth ofT. hamatum onP. viridicatum was increased with time. Viability ofP. viridicatum conidia decreased byT. hamatum with an increase in the incubation period. Chitinases and 1,3-β-glucanase enzyme activity ofT. hamatum increased with extending the incubation period onP. viridicatum mycelia up to maximum values at 72 and 84 h, respectively.T. hamatum led to a decrease in the production of citrinin byP. viridicatum on rice grains compared with the respective control values. http://www.phytoparasitica.org posting Dec. 19, 2004.     

取食不同寄主的草地贪夜蛾肠道微生物多样性分析

为绿色防控草地贪夜蛾Spodoptera frugiperda,基于16S rDNA和ITS高通量测序分析,对分别取食玉米、小麦以及田间常见杂草婆婆纳Veronica polita的草地贪夜蛾肠道细菌和真菌进行物种注释、多样性分析、物种组成分析及功能预测。结果显示,细菌注释共获得20门30纲72目106科164属214种,真菌注释共获得9门23纲46目90科154属237种。厚壁菌门、放线菌门和变形菌门为取食玉米、小麦和婆婆纳的草地贪夜蛾肠道优势细菌门,子囊菌门和担子菌门为取食玉米、小麦和婆婆纳的草地贪夜蛾肠道优势真菌门。肠球菌属Enterococcus为取食玉米、小麦和婆婆纳的草地贪夜蛾肠道细菌共同的优势属,相对丰度分别为70.86%、25.42%和72.02%;丝孢酵母属Tricho-sporon 和帚枝霉属 Sarocladium 为取食玉米的草地贪夜蛾肠道真菌的优势属,相对丰度分别为57.28%和17.38%,酵母菌目未分类属、小囊菌属Microascus和丝孢酵母属Trichosporon为取食小麦的草地贪夜蛾肠道真菌优势属,相对丰度分别为29.31%、27.01%和15.45%,双足囊菌科未分类属为取食婆婆纳的草地贪夜蛾肠道真菌优势属,相对丰度为61.79%。取食小麦的草地贪夜蛾肠道细菌群落的多样性最高,取食婆婆纳的草地贪夜蛾肠道真菌群落的多样性最高,取食婆婆纳的草地贪夜蛾肠道细菌和真菌群落的丰富度最高。取食玉米、小麦和婆婆纳的草地贪夜蛾肠道细菌群落功能主要与代谢通路相关,取食玉米、小麦和婆婆纳的草地贪夜蛾肠道真菌群落功能主要与基础代谢或生理功能相关。     

Resistance and Resistance Breeding in Ornamentals 1

Heritability studies in ornamentals with regard to Erwinia amylovora (Burrill) Winslow et al. were started shortly after the introduction of the pathogen into northern Europe. Since that time, approximately 8,000 plants from 17 genera of Rosaceae have been tested; 7 genera were reported to be susceptible: the economically important Cotoneaster, Crataegus, Cydonia, Pyracantha, Sorbus, and, in addition, Chaenomeles and Stranvaesia. Moreover, 9,000 Cotoneaster seedlings comprising 15 cultivars were tested and the surviving individuals used for breeding purposes. The variation between these first results reported in the different European countries and some American findings is considerable because of different inoculation procedures and various epidemiological conditions. However, resistance sources have been identified and it would be desirable to start co–operation in this field on an international level.     

Populations of predators and parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) after the application of eight biorational insecticides in vegetable crops

BACKGROUND: The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is an important pest of vegetables and many other crops worldwide. Eight biorational insecticides (based on oil, plant derivatives, insect growth regulator and fungus) were evaluated in the field for their influence on populations of six natural enemies of B. tabaci. Natural populations of two predators [Chrysoperla carnea Stephen (Neuroptera: Chrysopidae) and Orius spp. (Hemiptera: Anthocoridae)] and two genera of parasitoids [Encarsia spp. and Eretmocerus spp. (Hymenoptera: Aphelinidae)] were evaluated in eggplant (Solanum melongena L.). Also, augmented field populations of three predators [C. carnea, Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) and Macrolophus caliginosus (Wagner) (Hemiptera: Miridae)] were evaluated in cabbage (Brassica oleracea var. capitata L.), cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.). RESULTS: Regardless of natural enemy or crop, jojoba oil, Biovar and Neemix had the least effect on abundance of the natural enemies in comparison with the other insecticides during a 14 day evaluation period. Conversely, Admiral, KZ oil, Mesrona oil, Mesrona oil + sulfur and natural oil had a high detrimental effect on abundance of the natural enemies. CONCLUSION: These results demonstrate the differential effects of biorational insecticides for whitefly control on predators and parasitoids in the field. Published 2011 by John Wiley & Sons, Ltd.     

First report on the distribution of microsporidian infections of browntail moth (Euproctis chrysorrhoea L.) populations in Bulgaria

The distribution of microsporidian infections of browntail moth (Euproctis chrysorrhoea L.) populations in Bulgaria was studied. Of the 72 browntail moth populations in the regions of Balkan, Sredna Gora, Sakar Mountains, and Rodope Mountains, 21 were infected by Microsporidia. The Microsporidia belong to two genera – Nosema (Dihaplophasea, Nosematidae) and Endoreticulatus (Haplophasea, Encephalitozoonidae). Microsporidial infections caused by a Nosema were found in 14 populations, by an Endoreticulatus in 8 populations, and mixed infections of Nosema and Endoreticulatus were recorded from 3 populations. Endoreticulatus was present in Balkan, Sredna Gora, and the Sakar Mountains. Nosema infections were found in Sakar Mountains and Rodope, and mixed infections were recorded only from the Sakar Mountain populations.