Study on the Biology and Epidemiology of Uncinula necator---The Causal Agent of Grape Powdery Mildew Disease

This study was carried out during 2007-2009 in the vineyards of Ardebil province of lran to study the biology and the epidemiology of Uncinula necator--the causal agent of grape powdery mildew disease. The study concentrated on the survival and the initiation of primary inoculum of the fungal causal agent. Results of histopathological experiments indicated that U. necator survived as mycelium in the dormant buds of the grapes during winter season. Results of study on the effect of environmental factors on fungus biology showed that the pathogenic activity of the fungus began when the temperature was between 16-19 ℃ with a relative humidity more than 50%. It was also found that optimum temperature and relative humidity for the sporulation of U.necator was 20-25 ~C and 50%-100% respectively. According to the results, fungal conidia were trapped during formation of 5-6 true leaves and first disease symptoms were observed on the clusters on late June after fruit formation. Fungal cleistothecia were observed abundantly at the end of season on the leaves, petioles and twigs but they were not able to survive during winter. Formation of ascospores on young leaves was proved but their role as the primary inoculum was not supported by the results of this study. Results of this study and the new findings on the biology and epidemiology of U.necator may be of national and international interests for the management of powdery mildew disease which is one of the most destructive diseases around the world including Iran.

Morphometric discrimination between females of two isomorphic sand fly species, Phlebotomus caucasicus and Phlebotomus mongolensis(Diptera:Phlebotominae) in endemic and non-endemic foci of zoonotic cutaneous leishmaniasis in Iran

Objective: To delineate reliable morphological characteristics for identifying and separating female Phlebotomus caucasicus and Phlebotomus mongolensis which exist sympatrically in the main foci of zoonotic cutaneous leishmaniasis in Iran.Methods: Sand flies were collected using sticky trap papers from active colonies of rodent burrows installed from 16 catching sites. Morphometric measurements were analyzed of 87 Phlebotomus caucasicus and 156 Phlebotomus mongolensis. Univariate and multivariate analysis were carried out to determine significant morphometric variables for discrimination of the two species. Finally, seven morphological characteristics of 65 female Phlebotomus caucasicus and 124 female Phlebotomus mongolensis were described.Results: Univariate and multivariate analyses of 10 morphometric variables via Discriminant Function Analysis(DFA) and Principal Component Analysis(PCA) showed that five morphometric variables had an accuracy of 100% for discriminating female Phlebotomus caucasicus and Phlebotomus mongolensis. Moreover, PCA revealed that the five morphometric variables with the highest loadings separated these two species. Morphological studies on antennal flagellum(and its associated structures) and mouth-parts of female specimens demonstrated significant differences in several structures.Conclusions: The results show that morphological and morphometrical features can be used to discriminate two female isomorphic species, Phlebotomus caucasicus and Phlebotomus mongolensis accurately.

Effect of Different Bioassay Methods on Enzymatic Characteristics of Cotton Aphid, Aphis gossypfi Glover （Hemiptera：Aphididae）

In this study, the susceptibility of three populations of cotton aphid, Aph＆ gossypii Glover （Hemiptera：Aphididae） was assayed to imidacloprid （35SC） and thiametoxam （50WG）. The involvement of metabolic enzymes in the resistance strain of cotton aphid to the neonicotinoids was determined by the biochemical biomarkers and the resistance mechanism was determined as CaE. In another study, three different bioassay experiments were designed for detecting the susceptibility of cotton aphid to imidacloprid and thiametoxam and the effect of these two insecticides on the enzymatic activity of cotton aphid was assessed in the adult aphids treated with three different bioassay methods using a modified version of the FAO dip test, residue bioassay procedure and starvation method. Our findings suggested that the type of bioassay methods is very important when aphids＇ populations assess for the resistance against the neonicotinod insecticides. It has shown the starvation method is the most reliable method compared with other methods.

Molecular Study of a New Disease of Peach in Iran Associated with a Phytoplasma

In recent years, a disease has been reported to affect peach trees in Kurdistan province of Iran causing serious losses to the production. Main symptoms of disease include leaf stunting and yellowing, which lead to failure in fruit production at harvest. For diagnosis of disease and identification of the causal agent, symptomatic leaf samples were collected in Kurdistan orchards during summer 2010 and were carried to the laboratory. Total DNA was extracted from plant samples according to the standard procedures and indexed by grafting and nested PCR using phytoplasma generic primers, P1/P7 and R16F2n/R2. PCR products were characterized by RFLP technique and direct sequencing. The 16S rDNA sequences were compared with those of other phytoplasmas in GenBank. Phytoplasma rDNA was amplified from 20 out 35 samples. The 16S rDNA sequences of the phytoplasma were identified in Peach samples which showed 98% similarity to that of “Candidatus Phytoplasma phoenicium” which is considered to be the causal agent of Almond witches’ broom. Phylogenetic analysis of 16S rDNA sequences placed peach strains in Almond witches broom isolate as a member of pigeon pea witches broom (PPWB) group. Further studies on the epidemiology of “Ca. Phytoplasma phoenicium” and its vector(s) in Iran are recommended in order to identify new natural hosts and develop successful disease management programs.

Energy Intensity and Fitness Cost of Cotton aphid Exposure to Neonicotinoids

Three populations of Aphis gossypii of distinct susceptibility to neonicotinoids show differences in the accumulation and mobilization of energy reserves, what may allow the production of their defensive tools against two neonicotinoid insecticides without impairing their reproductive performance. Bioassays were also carried out for these aphid populations. According to the results obtained, the Ag-R population showed resistant rate significantly higher than the other two populations. Levels of some biochemical characteristics were determined in the resistant, susceptible and semi susceptible populations of cotton aphid. The results obtained in the assays with biochemical parameters indicated significant differences in activity among the populations, with higher activity in using glycogen in the Ag-R population. The inverse activity trends oft （generation time） and DT （doubling time） in both resistant and susceptible populations, one showing fitness disadvantage without insecticide exposure and the other not showing it, may underlay the mitigation of insecticide resistance physiological costs observed in the Ag-R population.

Nanoemulsified Mentha piperita and Eucalyptus globulus oils exhibit enhanced repellent activities against Anopheles stephensi

Objective:To formulate nanoemulsion from essential oils of Mentha(M.)piperita L.and Eucalyptus(E.)globulus L.and to compare their repellant activity with normal essential oils and N,N-diethyl-m toluamide(DEET)as a standard chemical compound.Methods:In this study,protection time of essential oils and DEET was evaluated on four human subjects using test cage,and their values were determined against Anopheles stephensi.Furthermore,ED50 values for the above essential oils were determined using the ASTM E951-94 method.The compositions of essential oils were determined using GC-MS,and droplet size and zeta potential of the nanoemulsion were measured with dynamic light scattering.Results:The results(expressed as mean±SD)showed that protection time of M.piperita 50%,M.piperita Nano 50%,E.globulus 50%,E.globulus Nano 50%,and DEET 25%was(2.89±0.45)h,(4.17±0.28)h,(0.96±0.27)h,(5.51±0.02)h,and(6.10±0.47)h,respectively.ED50 values were 29.10(95%CI:23.36-36.06)μg/cm^2 for Mentha,19.39(15.35-23.99)μg/cm^2 for Mentha Nano,36.10(28.70-48.01)μg/cm^2 for Eucalyptus,18.50(14.65-23.23)μg/cm^2 for Eucalyptus Nano,and 3.62(2.68-4.55)μg/cm^2 for DEET,respectively.E.globulus Nano and M.piperita Nano provided significantly longer protection than normal essential oils E.globulus and M.piperita(P<0.01).Conclusions:The preparation of nanoemulsion from the essential oils of M.piperita and E.globulus,significantly increases the protection time and reduces ED50 values of these essential oils,hence,M.piperita Nano and E.globulus Nano can be good alternatives to DEET and other chemical compounds.

茚虫威和六伏隆对小菜蛾卵、幼虫和成虫的药效(英文)

化学防治是世界各地防治小菜蛾Plutella xylostella(L.)的主要方法。选择对小菜蛾各发育阶段高效的杀虫剂有助于很好地控制这一害虫。本研究用浸叶法测定了茚虫威和六伏隆对小菜蛾卵、幼虫和成虫的毒性。茚虫威和六伏隆对小菜蛾卵的LC50值分别为201.40和37.32mg/L。茚虫威和六伏隆对3龄幼虫也有很好的毒性(茚虫威的LC50为4.82mg/L;六伏隆的LC50为1.48mg/L)。对成虫的毒性结果表明,这两种杀虫剂对成虫均没有理想的毒性(茚虫威的LC50为845.20mg/L;六伏隆的LC50为3438mg/L)。根据计算的LC50值,六伏隆对小菜蛾卵和幼虫的毒性比茚虫威高,但是茚虫威对成虫的毒性更高。

新烟碱类杀虫剂对麦扁盾蝽若虫和成虫的毒效(英文)

在伊朗,麦扁盾蝽Eurygaster integriceps是小麦和大麦上的主要害虫。新烟碱类杀虫剂是一类具有较强活性的杀虫剂,对刺吸式口器害虫具有良好的效果。本研究应用触杀和熏蒸两种生测方法测定了4种新烟碱类杀虫剂(噻虫嗪、吡虫啉、呋虫胺和啶虫咪)对麦扁盾蝽3龄若虫和成虫的毒效。触杀法生测结果显示,各杀虫剂对麦扁盾蝽没有强烈的触杀活性,但是在高浓度下(5000mg/La.i.),可见较高的死亡率。熏蒸法生测结果显示,所有杀虫剂对麦扁盾蝽的若虫和成虫均有较好的毒性。结果提示应用熏蒸方法可能是治理这一重要害虫的新方法。

Energy Metabolism Pattern in Cotton Aphid, Aphis gossypii Glover （Hem.： Aphididae） Exposure to Neonicotinoids

This study was mainly made on the role of energy revisers in cotton aphid, Aphis gossypii Glover （Hemiptera： Aphididae） countered with imidacloprid and thiametoxam. We measured used energy, available energy and the content of total energy in three strains of cotton aphid which were from very resistant to neonicotinoid, sup to semi-sensitive and sensitive speccies, respectively. It was observed changes in energy resources rate in all of the aphid strains at which each substrate was metabolized under stress. Our findings indicated among energy sources, total lipid in susceptible strain was increased in counter of spraying and it was decreased in resistance and semi sensitive strains. Whereas, total protein was decreased in all of the strains encountering with neonicotiniod stress. Total glycogen was increased significantly in different aphid strains and sugar was decreased in countered of spraying.

Sublethal effects of hexaflumuron on development and reproduction of the diamondback moth, Plutella xylostella （Lepidoptera： Yponomeutidae）

Effects of hexaflumuron at 10% lethal concentration （LC10） and LC25 on development and reproduction parameters of the diamondback moth, Plutella xylostella （Linnaeus, 1753） （Lep.： Yponomeutidae） were investigated. Estimated LC50, LC10 and LC25 values of leaf dip bioassay of hexaflumuron on the third instar larvae of the P xylostella were 1.48, 0.59 and 0.91 mg/L, respectively. Hexaflumuron decreased pupal weight in the parent generation at sublethal concentrations but in the offspring generation, this effect was not observed. Sublethal concentrations increased egg, first and second larval instar and pupa developmental time and shortened life span of adults, but did not change the third and fourth larval instars and pre-pupa developmental period. Also fecundity of females reduced significantly but hatchability of treatments and control were similar. Survival rate of pre-adult stages declined significantly at LC25 concentration. Reproduction parameters such as reproductive rate （R0） and intrinsic rate of increase in sublethal concentrations were significantly lower compared with control, but gross reproduction rate （GRR） at the LC10 concentration was increased and it could be hormoligosis. Also hexaflumuron significantly increased doubling time （Dt）. We conclude that the sublethal effects of hexaflumuron might exhibit significant effects on the population dynamics of P xylostella.

Functional response of Chrysoperla carnea （Neuroptera： Chrysopidae） to Helicoverpa armigera （Lepidoptera： Noctuidae） Effect of prey and predator stages

Understanding predator-prey interactions has a pivotal role in biological control programs. This study evaluated the functional response of three larval instars of the green lacewing, Chrysoperla carnea （Stephens）, preying upon eggs and first instar larvae of the cotton bollworm, Helicoverpa armigera Hubner. The first and second instar larvae of C. carnea exhibited typeⅡ functional responses against both prey stages. However, the third instar larvae of C. carnea showed a type II functional response to the first instar larvae of H. armigera, but a typeⅢ functional response to the eggs. For the first instar larvae of C. carnea, the attack rate on H. armigera eggs was significantly higher than that on the larvae, whereas the attack rate of the second instar C. carnea on H. armigera larvae was significantly higher than that on the eggs. For the third instar larvae of C. carnea, the attack rate on the larvae was 1.015±0.278/h, and the attack coefficient on the eggs was 0.036 ±0.005. The handling times of the third instar larvae on larvae and eggs were 0.087 ± 0.009 and 0.071 ± 0.001 h, respectively. The highest predation rate was found for the third instar larvae of C. carnea on H. armigera eggs. Results of this study revealed that the larvae of C. carnea, especially the third instar, had a good predation potential in controlling H. armigera eggs and larvae. However, for a comprehensive estimation of the bio- control abilities of C. carnea toward H, armigera, further field-based studies are needed.

Fungal diversity notes 1387-1511:taxonomic and phylogenetic contributions on genera and species of fungal taxa

This article is the 13th contribution in the Fungal Diversity Notes series,wherein 125 taxa from four phyla,ten classes,31 orders,69 families,92 genera and three genera incertae sedis are treated,demonstrating worldwide and geographic distri-bution.Fungal taxa described and illustrated in the present study include three new genera,69 new species,one new com-bination,one reference specimen and 51 new records on new hosts and new geographical distributions.Three new genera,Cylindrotorula(Torulaceae),Scolecoleotia(Leotiales genus incertae sedis)and Xenovaginatispora(Lindomycetaceae)are introduced based on distinct phylogenetic lineages and unique morphologies.Newly described species are Aspergillus lan-naensis,Cercophora dulciaquae,Cladophialophora aquatica,Coprinellus punjabensis,Cortinarius alutarius,C.mammil-latus,C.quercoflocculosus,Coryneum fagi,Cruentomycena uttarakhandina,Cryptocoryneum rosae,Cyathus uniperidiolus,Cylindrotorula indica,Diaporthe chamaeropicola,Didymella azollae,Diplodia alanphillipsii,Dothiora coronicola,Efibula rodriguezarmasiae,Erysiphe salicicola,Fusarium queenslandicum,Geastrum gorgonicum,G.hansagiense,Helicosporium sexualis,Helminthosporium chiangraiensis,Hongkongmyces kokensis,Hydrophilomyces hydraenae,Hygrocybe boertmannii,Hyphoderma australosetigerum,Hyphodontia yunnanensis,Khaleijomyces umikazeana,Laboulbenia divisa,Laboulbenia triarthronis,Laccaria populina,Lactarius pallidozonarius,Lepidosphaeria strobelii,Longipedicellata megafusiformis,Lophiotrema lincangensis,Marasmius benghalensis,M.jinfoshanensis,M.subtropicus,Mariannaea camelliae,Mel-anographium smilaxii,Microbotryum polycnemoides,Mimeomyces digitatus,Minutisphaera thailandensis,Mortierella solitaria,Mucor harpali,Nigrograna jinghongensis,Odontia huanrenensis,O.parvispina,Paraconiothyrium ajrekarii,Par-afuscosporella niloticus,Phaeocytostroma yomensis,Phaeoisaria synnematicus,Phanerochaete hainanensis,Pleopunctum thailandicum,Pleurotheciella dimorphospora,Pseudochaetosphaeronema chiangraiense,Pseudodactylaria albicolonia,Rhexoacrodictys nigrospora,Russula paravioleipes,Scolecoleotia eriocamporesi,Seriascoma honghense,Synandromyces makranczyi,Thyridaria aureobrunnea,Torula lancangjiangensis,Tubeufia longihelicospora,Wicklowia fusiformispora,Xenovaginatispora phichaiensis and Xylaria apiospora.One new combination,Pseudobactrodesmium stilboideus is pro-posed.A reference specimen of Comoclathris permunda is designated.New host or distribution records are provided for Acrocalymma fici,Aliquandostipite khaoyaiensis,Camarosporidiella laburni,Canalisporium caribense,Chaetoscutula juniperi,Chlorophyllum demangei,C.globosum,C.hortense,Cladophialophora abundans,Dendryphion hydei,Diaporthe foeniculina,D.pseudophoenicicola,D.pyracanthae,Dictyosporium pandanicola,Dyfrolomyces distoseptatus,Ernakula-mia tanakae,Eutypa flavovirens,E.lata,Favolus septatus,Fusarium atrovinosum,F.clavum,Helicosporium luteosporum,Hermatomyces nabanheensis,Hermatomyces sphaericoides,Longipedicellata aquatica,Lophiostoma caudata,L.clematidis-vitalbae,Lophiotrema hydei,L.neoarundinaria,Marasmiellus palmivorus,Megacapitula villosa,Micropsalliota globocys-tis,M.gracilis,Montagnula thailandica,Neohelicosporium irregulare,N.parisporum,Paradictyoarthrinium diffractum,Phaeoisaria aquatica,Poaceascoma taiwanense,Saproamanita manicata,Spegazzinia camelliae,Submersispora variabi-lis,Thyronectria caudata,T.mackenziei,Tubeufia chiangmaiensis,T.roseohelicospora,Vaginatispora nypae,Wicklowia submersa,Xanthagaricus necopinatus and Xylaria haemorrhoidalis.The data presented herein are based on morphological examination of fresh specimens,coupled with analysis of phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their evolutionary relationships.