EVALUATION OF NUCLEAR AND MITOCHONDRIAL RIBOSOMAL PHYLOGENETIC MARKERS FOR THE TAXONOMIC CLASSIFICATION OF ENTOMOPATHOGENIC FUNGI: A COMPARATIVE STUDY BASED ON ISOLATES FROM UZBEKISTAN
Authors: Anaida G. Guzalova, Kakhramon Ergashev, Erkin N. Abdullaev, Zafar F. Izmailov, Andreas
Abstract: Five ribosomal phylogenetic markers – an internal fragment of the mitochondrial small rDNA, an internal fragment of the nuclear 18S rDNA, the complete nuclear 5.8S rDNA and both internal transcribed spacer (ITS) elements of the nuclear rDNA cluster - were compared for their respective suitability to provide the basis for a rapid and reliable taxonomic screening of filamentous fungi isolated from insects, with a particular focus on a generic and specific classification of entomopathogenic hyphomycetes belonging to the form-genera Beauveria, Metarhizium, Paecilomyces and Lecanicillium. While a low density of phylogenetically useful information made both nuclear coding sequences unlikely candidates for the purpose in question, the mitochondrial marker proved appropriate for strain assignments at the genus level; both ITS elements were found to allow for a generic as well as specific classification. The markers were subsequently used to classify entomopathogenic fungal strains isolated from insects in Uzbekistan that turned out to belong to the species Beauveria bassiana and Metarhizium anisopliae as well as to the genera Aspergillus, Fusarium and Trichoderma.
Key words: phylogeny, taxonomy, Beauveria, Metarhizium
FUNCTIONAL RESPONSE OF HIPPODAMIA VARIEGATA (COL.: COCCINELLIDAE) ON APHIS FABAE (HOM.: APHIDIDAE) IN LABORATORY CONDITIONS
Authors: Reza Jafari
Abstract: Functional response is one of the most important behavioral characteristics that reveal different aspects of prey-predator interactions. In this study, functional response of the amber ladybird, Hippodamia variegata (Goeze) attacking the black bean aphid, Aphis fabae (Scopoli) were investigated. Different level of aphid densities as: 20,40,60,80,100,120,140,160 and 180 were used. Each density was placed in a test cage (6×11×23 cm) and then exposed to a 24h adult. The experiments were carried out at 25±1°C, %60±5 r.h. and 16:8 (L:D) photoperiod. Logistic regression was used to distinguish the shape of the functional response (type п or ш). Nonlinear least-square regression was used to estimate the attack rate (a) and handling time (Th ). Nicholson model was used to determine per capita searching efficiency. Logistic regression suggested a type п response on A. fabae adults. Searching efficiency, handling time and estimated maximum percent of consume preys were 0.00078, 0.1774 and 135.29 respectively.
Key words: Functional response, Hippodamia variegata
STATUS OF NEW ACARICIDES VIS-A-VIS CONVENTIONAL ACARICIDES AGAINST THE RED SPIDER MITE, OLIGONYCHUS COFFEAE (ACARINA: TETRANYCHIDAE) IN TEA PLANTATIONS OF DARJEELING PLAINS, INDIA
Authors: Somnath Roy, G. Gurusubramanian, Ananda Mukhopadhyay
Abstract: The Red spider mite, Oligonychus coffeae (Acarina: Tetranychidae), is the most destructive pest of tea. In the present experiment, the status of new acaricides vis-à-vis conventional acaricides in Darjeeling plains population of O. coffeae was estimated. The LC50 (expressed in ppm) values of ethion, dicofol, profenofos, propargite, fenpropathrin, fenpyroximate, fenazaquin and abamectin were 687.18, 534.04, 241.684, 90.256, 12.549, 6.196, 4.319 and 2.405 respectively. Of all the acaricides tested abamectin is the most toxic and ethion was the least toxic. The LC95 (ppm) values were also calculated. This kind of study would serve as ready-reckoner of the selection of acaricides for the management of field strains and also helpful in development of resistant management strategies for this important polyphagous mite pest.
Key words: Oligonychus coffeae, acaricides, Darjeeling plains population.
DISTRIBUTION AND OIL CROPS ASSOCIATION OF PLANT PARASITIC NEMATODES IN EGYPT
Authors: A.M. Korayem, M.M. Ahmed, M.M.M. Mohamed
Abstract: Eleven genera of plant parasitic nematodes associated with rapeseed, peanut, soybean and sunflower oil crops were recovered from ten governorates in Egypt. Helicotylenchus, Hoplolaimus Meloidogyne, and Pratylenchus were the most frequent nematodes occurring with high population densities, frequency of occurrence and prominence values.
Key words: distribution, plant nematodes, oil crops
PRELIMINARY STUDIES ON RHAGOLETIS CERASI L. ECOLOGICAL CONTROL
Authors: Constantina Chireceanu, Viorel Fatu
Abstract: Preliminary experiments carried out under laboratory to evaluate the effect of four Romanian isolates of the entomopathogenic fungus Beuveria bassiana upon adults of European Cherry fruit fly Rhagoletis cerasi L. (Diptera: Tephritidae) at R&D Institute for Plant Protection, Bucharest in 2007. A maxim level of 76% mortality of the flies was obtained in case of the BbOb 1\95 strain isolated from Operophtera brumata species on Acacia sp. As well as, two initial field experiments were conducted in connection with the efficiency of the covering the soil under canopy cherry trees area to prevent R. cerasi emerging adults. Percentages of 5,5 and 8,6% infested cherries by the cherry fly were obtained in plots where the ground around the cherry three were covered with mowed grass and polyethylene, respectively, comparatively with the insecticide application in commercial orchard (18,50%) and untreated control plots (24,70%).
Key words: Rhagoletis cerasi, biological method, Beauveria bassiana, cultural methods
CHARACTERIZATION OF HERBICIDAL POTENTIAL OF TENUAZONIC ACID ISOLATED FROM ALTERNARIA ALTERNATA FOR THE MANAGEMENT OF PARTHENIUM HYSTEROPHORUS
Authors: Bhagwan S. Sanodiya, Gulab S. Thakur, Mousumi Debnath, A.K. Pandey, G.B.K.S. Prasadd, P.S. Bisen
Abstract: Microbial secondary metabolites are potential herbicides with unique mode of action. Cell Free Culture Filtrate (CFCF) of Alternaria alternata was evaluated for its phytotoxicity against Parthenium hysterophorus . Shoot cut, seedling and detached leaf bioassays revealed the presence of a toxic metabolite in the CFCF. A significant reduction in chlorophyll and protein content were also noticed. Phytotoxic moiety was purified and characterized by using solvent partition, thin layer chromatography (TLC), FTIR and 1H NMR analysis. The acetone extract induced maximum phytotoxic damage at a concentration of 100 μg ml–1 and TLC purified fraction exhibited herbicidal potential. The toxic compound was identified as Tenuazonic acid on comparison with FTIR and 1 H NMR spectra. This is the first evidence of the herbicidal potential of Tenuazonic acid against Parthenium hysterophorus produced by submerged fermentation of Alternaria alternata.
Key words: Alternaria alternata, Parthenium hysterophorus, Mycoherbicide, Tenuazonic acid
ATTRACT & KILL TECHNIQUE AGAINST LOBESIA BOTRANA DEN.&SCHIFF. (LEPIDOPTERA: TORTRICIDAE) IN ROMANIA
Authors: Silvia Cazacu, Sonica Drosu, Loreta Dumitrascu, Lucia Gansca, Ion Oprean
Abstract: This paper presents the results of the studies carried out during 2006-07 in 3 vineyards situated in the representative wine growing centres of Romania (Research Development Institute for Viticulture Valea Calugareasca situated in middle of the country, Research Development Station for Viticulture Murfatlar in the South-Eastern and Research Development Station for Viticulture Iasi in Eastern part of the country) with a product PRELUDIU LB used in Attract & Kill technique. The product, obtained by Research Institute for Chemistry "Raluca Ripan" Cluj-Napoca, consists of a viscous formulation containing specific grapevine moth (Lobesia botrana) pheromone (E-9-dodecenylacetate and E,Z-7,9-dodecadienyl acetate) and a pyrethroid. The formulation was applied uniformly on the branches of the vines, by hand (400g/ha), 1-2 time in the season, depending of the infestation level. The efficacy of a Romanian product PRELUDIU LB was ranging between 61.20-81.37% in the two years study; the losses of the yield were reduced with 25-33%. The results of this strategy show that it can compete with conventional spray applications and is therefore a good alternative for grapevine moth control in integrated wine growing.
Key words: grapevine moth, pheromones, Attract & Kill technique
THE INVERTEBRATE FAUNA ASSOCIATED OF THE WHEAT AGROCENOSIS IN AMZACEA, CONSTANTA COUNTY
Authors: Constantina Chireceanu, Grigore Margarit, Vasile Jinga, Gheorghe Pascu, Dumitru Manole
Abstract: Species composition, the abundance and the domination of the invertebrate fauna associated with agrocenosis of two wheat fields in the Amzacea district, Constanta County (south-eastern Romania) in 2005y. A total of 1553 specimens of invertebrates representing 56 taxons were recorded. Haplothrips triticii Kurdj. Colembolla, Lumbricidae, Enchitreidae and Anoxia villosa were eudominants. The group of dominants consisted of Macrosiphum avenae F., Formicidae, Harpalus pubescens and Aranea, Opatrum sabulosum L., Brachycera. Anoxia villosa recorded a density of 3-16 larvae/mp. The ratio between the total phytophagous and the useful fauna (zoophagous and pantophagous) was 1. 87:1.
Key words: invertebrate fauna, wheat field, Amzacea