10 research outputs found
Not Available
Not AvailableFungicides of demethylation inhibitor (DMI) group are used worldwide for the management of Erysiphe necator but are
associated with medium to high risk of development of resistance in the pathogen. Till date there was no report on the presence of DMI resistance in E. necator isolates from the major grape growing regions in tropical India, though there were instances of DMI fungicides providing less than accepted levels of powdery mildew control. In this study, 54 E. necator isolates were collected during 2015–2017 from vineyards located in different geographical regions of India. The isolates were tested for their sensitivity to the commonly used DMI fungicide, myclobutanil, using leaf disc bioassay. Four isolates were sensitive (MIC 10 μg/ml) to the fungicide myclobutanil. The resistance factor (RF) ranged from 1.5 to 295. In PCR amplification of a specific allele, the product specific for A495T mutation was produced only in the 43 isolates with RF > 4. The CYP51 gene sequence analysis confirmed A495T mutation leading to Y136F change associated with high levels of resistance to DMI fungicides. Cross resistance studies among the DMI fungicides showed that 11 out of 13 myclobutanil resistant isolates were also resistant to difenoconazole and tetraconazole. Three myclobutanil sensitive isolates were also sensitive to difenoconazole and tetraconazole. Detection of resistance in E. necator isolates from the major grape growing region of tropical India stresses on the need for developing resistance management strategies.Not Availabl
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Not AvailableQuinone outside inhibitor (QoI) fungicides are used worldwide for the management of Erysiphe necator but with associated problem of resistance development in the pathogen. Twenty ninr E.necator isolates were collected during 2015-2016 from different geographical regions of India. In leaf disc bioassay using azoxystrobin, the EC50 of four isolates from research farms was <1 ug/ml while 25 isolates from commercial vineyards had produced a 100 bp PCR product with G143A mutant allele specification of cytochrome b gene (Cyt b) and used for amplification of the gene from two resistant and two sensitive isolates. Alignment of amino acid swquences showed that the QoI resistant isolates harboured a G143A mutation, which was absent in the sensitive isolates. The two haplotypes of Cyt b gene from a resistant isolate, SAA2, and a sensitive isolate, HP1, have been deposited in GenBank under accession numbers KY418049 and KY418048, respectively. This is the first report of presence of QoI resistant isolates of E.necator from India. Studies point out the need for developing resistance management strategies by interspersing bio-control ahents with judicious use of fungicides.Not Availabl
First record of occurrence of Dervishiya cadambae on grapevine, Vitis vinifera, along with its morphological and molecular identification and pathogenicity evaluation potential of Metarhizium brunneum as its biocontrol agent
Not AvailableIncreasing demand for grapes (Vitis vinifera L.) worldwide makes it a high-value crop and also an important, valuable export
commodity for India. In February 2016, a vineyard from Maharashtra, India was identified with entirely new insect damage symptoms from those observed earlier. After, further inspection, a new type of wood borer was noticed which was later identified as
Dervishiya cadambae (Moore) (Lepidoptera Cossidae). D. cadambae is known as a major pest of Tectona grandis L.f. plantations
in Kerala, Karnataka and Tamil Nadu states of India and causes extensive damage to the timber. Surveys were conducted in affected
vineyards to assess the extent of infestation from 2016 to 2018. In 20 infested vineyards located in Sangli and Nashik districts of
Maharashtra, 12-72% of grapevines were found to have active infestations. Young larvae fed under the bark and later instars bored
inside and made galleries. D. cadambae caused extensive damage to the sapwood and heartwood of grapevine stem and reduced
both vitality and productivity of the vines. Deoxyribonucleic acid (DNA) barcode for this new pest of grapevines was also provided.
The DNA barcode grouped D. cadambae in the clade of Cossidae samples supported with a bootstrap value of 85% in phylogenetic
analysis. To our knowledge, this is the first record of D. cadambae occurrence on V. vinifera. A green muscardine fungus was isolated from the field infected larvae of D. cadambae. The pathogenicity test confirmed Koch’s postulates. The fungus was identified
as Metarhizium brunneum (Petch), which proved to be an efficient antagonist of this pest in laboratory bioassays.Not Availabl
Not Available
Not AvailableDeoxyribonucleic acid barcoding, using mitochondrial cytochrome c oxidase-1 sequence, is an accurate and rapid identification method for insect-taxa and independent of life-stages, sex and polymorphism. The present study aimed at providing deoxyribonucleic acid barcode for the correct identification of Stromatium barbatum (Fabricius), a new pest of grapevines in India. Morphometric analysis and pictorial illustrations of important morphological features and life-stages were also documented for future reference. Average length and breadth (in mm) were 1.012 ± 0.10 and 0.49 ± 0.07 for egg, 1.52 ± 0.15 and 0.50 ± 0.04 for neonate-grub, 35.12 ± 0.47 and 7.08 ± 0.12 for fully matured grub, 26.0 ± 0.25 and 8.64 ± 0.12 for pupa, 21.20 ± 2.51 and 6.02 ± 0.62 for adult-male, and 22.47 ± 2.26 and 6.67 ± 0.75 for adult-female, respectively. Antennae was filiform which was longer in males (30.63 ± 5.89 mm) than females (22.55 ± 4.84 mm). The barcode showed 86% match with closely related S. longicorne and in Neighbor Joining analysis formed monophyletic clade with S. longicorne suggesting correct genus-level identification. Specimens used for sequencing were morphologically identified by an expert taxonomist and compared with type specimens before barcoding and sequences were submitted to National Center for Biotechnology Information. The barcode was put to test for confirmation of size-polymorphism. Cytochrome c oxidase-1 regions were sequenced for morphologically identified S. barbatum large male (2.6 cm), large female (2.9 cm), small male (1.6 cm) and small female (1.8 cm). These sequences showed B2.5% divergence among each other and B2.5 divergence with the DNA barcode confirming that the four specimens of different sizes belonged to same species and variation was due to size-polymorphism.Not Availabl
Not Available
Not AvailableDeoxyribonucleic acid barcoding, using mitochondrial
cytochrome c oxidase-1 sequence, is an accurate
and rapid identification method for insect-taxa and independent
of life-stages, sex and polymorphism. The present
study aimed at providing deoxyribonucleic acid barcode
for the correct identification of Stromatium barbatum
(Fabricius), a new pest of grapevines in India. Morphometric
analysis and pictorial illustrations of important
morphological features and life-stages were also documented
for future reference. Average length and breadth (in
mm) were 1.012 ± 0.10 and 0.49 ± 0.07 for egg,
1.52 ± 0.15 and 0.50 ± 0.04 for neonate-grub,
35.12 ± 0.47 and 7.08 ± 0.12 for fully matured grub,
26.0 ± 0.25 and 8.64 ± 0.12 for pupa, 21.20 ± 2.51 and
6.02 ± 0.62 for adult-male, and 22.47 ± 2.26 and
6.67 ± 0.75 for adult-female, respectively. Antennae was
filiform which was longer in males (30.63 ± 5.89 mm) than females (22.55 ± 4.84 mm). The barcode showed
86% match with closely related S. longicorne and in
Neighbor Joining analysis formed monophyletic clade with
S. longicorne suggesting correct genus-level identification.
Specimens used for sequencing were morphologically
identified by an expert taxonomist and compared with type
specimens before barcoding and sequences were submitted
to National Center for Biotechnology Information. The
barcode was put to test for confirmation of size-polymorphism.
Cytochrome c oxidase-1 regions were sequenced
for morphologically identified S. barbatum large male
(2.6 cm), large female (2.9 cm), small male (1.6 cm) and
small female (1.8 cm). These sequences showed B2.5%
divergence among each other and B2.5 divergence with the
DNA barcode confirming that the four specimens of different
sizes belonged to same species and variation was due
to size-polymorphism.Not Availabl
Not Available
Not AvailableDeoxyribonucleic acid barcoding, using mitochondrial
cytochrome c oxidase-1 sequence, is an accurate
and rapid identification method for insect-taxa and independent
of life-stages, sex and polymorphism. The present
study aimed at providing deoxyribonucleic acid barcode
for the correct identification of Stromatium barbatum
(Fabricius), a new pest of grapevines in India. Morphometric
analysis and pictorial illustrations of important
morphological features and life-stages were also documented
for future reference. Average length and breadth (in
mm) were 1.012 ± 0.10 and 0.49 ± 0.07 for egg,
1.52 ± 0.15 and 0.50 ± 0.04 for neonate-grub,
35.12 ± 0.47 and 7.08 ± 0.12 for fully matured grub,
26.0 ± 0.25 and 8.64 ± 0.12 for pupa, 21.20 ± 2.51 and
6.02 ± 0.62 for adult-male, and 22.47 ± 2.26 and
6.67 ± 0.75 for adult-female, respectively. Antennae was
filiform which was longer in males (30.63 ± 5.89 mm) than females (22.55 ± 4.84 mm). The barcode showed
86% match with closely related S. longicorne and in
Neighbor Joining analysis formed monophyletic clade with
S. longicorne suggesting correct genus-level identification.
Specimens used for sequencing were morphologically
identified by an expert taxonomist and compared with type
specimens before barcoding and sequences were submitted
to National Center for Biotechnology Information. The
barcode was put to test for confirmation of size-polymorphism.
Cytochrome c oxidase-1 regions were sequenced
for morphologically identified S. barbatum large male
(2.6 cm), large female (2.9 cm), small male (1.6 cm) and
small female (1.8 cm). These sequences showed B2.5%
divergence among each other and B2.5 divergence with the
DNA barcode confirming that the four specimens of different
sizes belonged to same species and variation was due
to size-polymorphism.Not Availabl
Not Available
Not AvailableIdentifying a superior bio-control strain is the first step in developing a successful bio-control strategy for any disease. Field trials were conducted to systematically screen six potential Trichoderma isolates for control of powdery mildew disease during 2013–2016. Treatments were applied as foliar sprays with a simple liquid formulation of Trichoderma containing 5 ×106 spores ml−1. The preliminary scale, small scale, and field scale trials showed that isolates NAIMCC-F-01938 and NAIMCC-F-01965 were superior to the other four Trichoderma isolates reducing disease by 43.67–50.36% and 35.71–53.40% respectively. Analysis of ITS, act, rpb2 and tef1 genes showed homology of strains NAIMCC-F-01938 and NAIMCC-F-01965 to T. afroharzianum and T. asperelloides respectively. Both isolates produced an array of enzymes implicated in bio-control activities. In coculture studies on grape leaves, Trichoderma hyphae grew towards and coiled around Erysiphe necator conidia, caused distortion of conidial structure and overgrew the powdery mildew colonies. T. afroharzianum showed higher tolerance to fungicides commonly used in powdery mildew management. In the large scale demonstration trial it showed 43% reduction in disease severity as compared to the untreated control. Furthermore, introducing two late season T. afroharzianum applications in a fungicide spray schedule, as replacement for sulphur, enhanced powdery mildew control by 31% as compared to the only fungicide schedule. The study shows that the T. afroharzianum strain NAIMCC-F-01938 can be positioned with safe fungicides for enhanced control of powdery mildew in vineyards.Not Availabl
New triazole-based Schiff base ligands and their Co(II) and Ni(II) complexes as biological potent molecules: Chemical preparation, structural elucidation and biological studies
Preparation of sequence of Co(II) and Ni(II) metal complexes (C1a - C3a and C1b - C3b) of bidentate ligands (L1 - L3) has been resulted from the condensation of substituted 1,2,4-triazole with various substituted 1,3-diphenyl-1H-pyrazole-4-carbaldehyde are described in the present study. The structures of synthesized complexes were established by elemental investigation, IR, mass spectroscopy and TGA examinations. The data confirmed that bonding through the nitrogen atom from imine group and sulfur atom of triazole, ligand get integrated with the metal ions in a bidentate nature, gave an octahedral geometry to the complexes. The antibacterial activities have been tested against S. aureus Gram-positive bacteria and E. coli Gram-negative bacteria. Further, through DPPH radical scavenging capacity assay the antioxidant activity values were quantified; all the compounds demonstrate outstanding antioxidant activities. Using molecular docking and highest binding affinities for biological targets, the ligand and complex interactions have been studied. The in vitro anti-proliferative nature of synthesized ligands and their Ni(II) and Co(II) complexes were appraised with the help of SRB assay against Human hepato carcinoma cell (Hep-G2), Lung cells (A-549), Breast cell (MCF-7), Prostate cell (PC-3). Anti-tubercular studies revealed that the complex demonstrates a greater anti-tubercular activity than the analogous ligands