Systematic analyses with genomic and metabolomic insights reveal a new species, Ophiocordyceps indica sp. nov. from treeline area of Indian Western Himalayan region

Ophiocordyceps is a species-rich genus in the order Hypocreales (Sordariomycetes, Ascomycota) depicting a fascinating relationship between microbes and insects. In the present study, a new species, Ophiocordyceps indica sp. nov., is discovered infecting lepidopteran larvae from tree line locations (2,202–2,653 m AMSL) of the Kullu District, Himachal Pradesh, Indian Western Himalayan region, using combinations of morphological and molecular phylogenetic analyses. A phylogeny for Ophiocordyceps based on a combined multigene (nrSSU, nrLSU, tef-1α, and RPB1) dataset is provided, and its taxonomic status within Ophiocordycipitaceae is briefly discussed. Its genome size (~59 Mb) revealed 94% genetic similarity with O. sinensis; however, it differs from other extant Ophiocordyceps species based on morphological characteristics, molecular phylogenetic relationships, and genetic distance. O. indica is identified as the second homothallic species in the family Ophiocordycipitaceae, after O. sinensis. The presence of targeted marker components, viz. nucleosides (2,303.25 μg/g), amino acids (6.15%), mannitol (10.13%), and biological activity data, suggests it to be a new potential source of nutraceutical importance. Data generated around this economically important species will expand our understanding regarding the diversity of Ophiocordyceps-like taxa from new locations, thus providing new research avenues

Chemical Composition and Larvicidal Activities of the Himalayan Cedar, Cedrus deodara Essential Oil and Its Fractions Against the Diamondback Moth, Plutella xylostella

Plants and plant-derived materials play an extremely important role in pest management programs. Essential oil from wood chips of Himalayan Cedar, Cedrus deodara (Roxburgh) Don (Pinales: Pinaceae), was obtained by hydrodistillation and fractionated to pentane and acetonitrile from which himachalenes and atlantones enriched fractions were isolated. A total of forty compounds were identified from these fractions using GC and GC-MS analyses. Essential oils and fractions were evaluated for insecticidal activities against second instars of the diamondback moth, Plutella xylostella L. (Lepidoptera: Yponomeutidae), using a leaf dip method. All samples showed promising larvicidal activity against larvae of P. xylostella. The pentane fraction was the most toxic with a LC50 value of 287 µg/ml. The himachalenes enriched fraction was more toxic (LC50 = 362 µg/ml) than the atlantones enriched fraction (LC50 = 365 µg/ml). LC50 of crude oil was 425 µg/ml and acetonitrile fraction was LC50 = 815 µg/ml. The major constituents, himachalenes and atlantones, likely accounted for the insecticidal action. Present bioassay results revealed the potential for essential oil and different constituents of C. deodara as botanical larvicides for their use in pest management

Determination of chlorpyrifos 20% EC (Dursban 20 EC) in scented rose and its products

The method for determination of chlorpyrifos is validated and dissipation behaviour of residue in scented rose and percent transfer in different products is described. GC–electron-capture detection with a HP-1, 30m × 0.53 mm, 3.0 �m capillary column and nitrogen at 1 ml/min was used in the study. Plant matrices studied were: leaves, flowers, soil, rose water, absolute and concrete. Detector response linearity and sensitivity, limit of detection and determination, percent recovery were determined based on area response (mm2) of the standard. Analytical field and laboratory samples (rose water by hydro-distillation of the flowers, concrete and absolute by hexane extraction and condensation) were analysed for evaluation of the method. Samples were extracted with acetone, partitioned with water, saturated sodium chloride solution and dichloromethane. The organic layer was rotary-evaporated to 2ml for cleanup with silica–carbon column. The column was eluted with dichloromethane–toluene–acetone (10:2:2, v/v/v) and the derived solution was rotary-evaporated to 5ml for end analysis. Matrix enhancement effect was observed for leaf and soil samples for which corrective approach was followed to compensate for overestimation of the residue. Limit of detection for chlorpyrifos standard was 0.05 mg/l with good linearity of detector response (R2 = 0.99). Percent recovery ranged from 78 to 117% in different plant matrices (fortification level 1, 4 and 8 mg/l). Dissipation behaviour showed that chlorpyrifos was below detection limit by the 12th day of application on the scented rose with half life of 3.40 days on leaves and 3.10 days on flowers at 0.1% dosage. Percent transfer studies showed that 5.71, 46.91 and 38.80% of the residue from flowers was transferred to rose water, concrete and absolute, respectively. © 2004 Elsevier B.V. All rights reserved

Comparative toxicities of novel and conventional acaricides against different stages

Adulticidal, ovicidal and nymphicidal effects of different newer acaricides along with some conventional one were evaluated on the life stages of a susceptible laboratory strain of two-spotted spider mite (TSMM), Tetranychus urticae Koch (Acarina: Tetranychidae) using a spray method. Abamectin was found to be the most toxic to the adults (LC50 = 0.39 ppm) followed by fenpyroximate (5.67 ppm), spiromesifen (12.53 ppm), chlorfenapyr (32.24 ppm), propargite (77.05 ppm) and dicofol (146.65 ppm). Hexythiazox was least toxic. There was no egg hatching when eggs were sprayed with one third of the recommended concentration of spiromesifen. This was statistically significantly different from all other treatments (fenpyroximate, chlorfenapyr, propargite, dicofol and hexythiazox) which were, however, at par with each other. Based on the 10th day observations, the ovicidal activity of spiromesifen (100%) was followed by dicofol (7.78% egg mortality) and hexythiazox (6.67%). Almost no effect on hatching was observed in both abamectin and chlorfenapyr treatment (0.54%). In case of propargite, all the treated eggs hatched. Abamectin resulted in highest nymphal mortality (96.05%) followed by dicofol (94.51%), hexythiazox (90.24) propargite (90.00), chlorfenapyr (89.33) and fenpyroximate (86.84%) and all the treatments were at par with each other and statistically different from the control. The present study revealed that abamectin, spiromesifen, hexythiazox, fenpyroximate and chlorfenapyr acaricides can alternatively be used for effective management of the mites

FIELD EVALUATION OF BIFENAZATE (ACRAMITE 50WP) FOR CONTROL OF TEA MITES

Insects and mites are the most damaging of arthropod pests to tea (Camellia sinensis (L.) O. Kuntze) causing yield losses of 5–55%. Various mite species are associated with tea monocultures. In the Kangra valley, Himachal Pradesh, India red spider mites (Oligonychus coffeae) and scarlet mites (Brevipalpus phoenicis) are prevalent during June-July. For mite control, various conventional acaricides are used but resistance has developed to most of them. In India, few acaricides are recommended for controlling mites in tea. However, there are many new risk reduced selective acaricides which are reported to control mites effectively on crops other than tea. Two seasons field bioefficacy trials of bifenazate (Acramite 50WP) were conducted against red spider mites at different application rates (@ 100, 125, 175, 200, 250 g/ha) and results were compared with the propargite 57 EC (@1 l/ha). In season 1, a single spray of bifenazate @250 g/ha provided 63% control up to 35 days post treatment. Acramite @250, 200, 175, and 125 g/ha provided mite control which was not significantly different from each other. In season 2, a repeat spray was made on day 14 and treatments @250 and 200 g/ha provided 91–93% control up to 35 days. Treatments @ 175 and 125 g/ha provided 84–86% control similar to propargite @1 l/ha. In view of the per cent control of the population over a period of 35 days and depending on the situations, Acramite @200 or 125 g/ha with a follow up spray after 14 days is recommended for the control of tea mites

ANALYTICAL METHOD FOR DETERMINATION OF ORGANOCHLORINE PESTICIDES IN TEA BREWS USING SINGLE-DROP MICROEXTRACTION WITH GC-ECD

The single drop microextraction method was developed for the determination of ten organochlorine pesticides in tea brews using gas chromatograph-electron capture detector. The optimized parameters for effective extraction required a 2 μL drop of n-hexane at the tip of a microsyringe immersed in 5 mL of a diluted tea brew sample for 25 min and stirred at 600 rpm. The limit of detection in the range of 0.01 to 0.025 μg/L, with relative standard deviation of repeatability and reproducibility, was in the range of 1–10 and 8–24%. The relationship of the measured signal was a linear function (>0.9863) of concentration and the recovery method ranged from 92–116%. The single drop microextraction method showed the advantage of being easy to operate, low consumption of organic solvent, and high extraction efficiency