MOLECULAR CHARACTERIZATION OF BEGOMOVIRUS INFECTING ABUTILON GLAUCUM IN SOUTH GUJARAT REGION

Weeds are potential sources of primary inoculum of viruses and play an important role in their persistence and spread. During the rainy season of 2010 - 2012, several plants of Abutilon glaucum in and around Navsari Agricultural university have been found with vein yellowing symptoms. In severe cases, the chlorosis extends into interveinal areas, resulting in complete yellowing of the leaves. Leaf samples from different plants showing severe symptoms were collected and tested for the presence of begomoviruses using PCR assay with the sets of degenerate primers designed to amplify part of the DNA-A strand. A PCR product of the expected sizes (750bp) was obtained with all infected samples. A 696 bp sequence of DNA-A molecule was obtained and submitted to GenBank (Accession Nos. JX258326). The highest nucleotide identity of 93% (BLASTn, NCBI) was obtained with Kenaf leaf curl virus-[India:Kaisarganj:2007]. The phylogenetic reconstruction were done by comparing sequence with other begomovirus AV1 gene. A survey of literature revealed that there is no record of a viral affecting this weed and, therefore, this is the first report of a viral disease affecting this weed plant

MOLECULAR CHARACTERIZATION OF BEGOMOVIRUS INFECTING ABUTILON GLAUCUM IN SOUTH GUJARAT REGION

Weeds are potential sources of primary inoculum of viruses and play an important role in their persistence and spread. During the rainy season of 2010 - 2012, several plants of Abutilon glaucum in and around Navsari Agricultural university have been found with vein yellowing symptoms. In severe cases, the chlorosis extends into interveinal areas, resulting in complete yellowing of the leaves. Leaf samples from different plants showing severe symptoms were collected and tested for the presence of begomoviruses using PCR assay with the sets of degenerate primers designed to amplify part of the DNA-A strand. A PCR product of the expected sizes (750bp) was obtained with all infected samples. A 696 bp sequence of DNA-A molecule was obtained and submitted to GenBank (Accession Nos. JX258326). The highest nucleotide identity of 93% (BLASTn, NCBI) was obtained with Kenaf leaf curl virus-[India:Kaisarganj:2007]. The phylogenetic reconstruction were done by comparing sequence with other begomovirus AV1 gene. A survey of literature revealed that there is no record of a viral affecting this weed and, therefore, this is the first report of a viral disease affecting this weed plant

IDENTIFICATION OF RAPD AND ISSR MAKERS FOR RESISTANCE AGAINST MUNGBEAN YELLOW MOSAIC VIRUS IN MUNGBEAN (VIGNA RADIATA L.) UNDER SOUTH GUJARAT AGRO CLIMATIC CONDITION OF INDIA

The present study was undertaken to identify genetic variation and tightly linked marker associated with mungbean yellow mosaic virus (MYMV) resistance from different mungbean lines. Out of 200 RAPD markers, OPG-5, OPJ- 18 and OPM-20 were proved to be the best markers for the study of polymorphism as it produced 28, 35, 28 amplicons respectively with overall polymorphism was found to be 70.17 %. Out of 17 ISSR markers used, DE- 16 proved to be the best marker as it produced 61 amplicons and 15 scorable bands and showed highest polymorphism among all. The combined dendrogram obtained from these RAPD and ISSR indicated two clearly visible clusters where all resistant lines viz., NAUMR1, NAUMR2, NAUMR3 and MEHA clearly separated from susceptible GM4. Here validation of these data could be compare with phenotypic character in the field. Once these markers are identified, they can be used to detect the QTLs linked to MYMV resistance in mungbean breeding programs, as a selection tool in early generations and further use in developing segregating material

Evaluation of Botanicals against Powdery Mildew (Oidium mangiferae Berthet) of Mango (Mangifera indica L.)

Mango (Mangifera indica L.) belongs to the family Anacardiaceae and is a native of the Indo-Burma (now Myanmar) region. The fungal diseases occur in higher proportions leading to huge economic losses for the growers. Out of various fungal diseases, powdery mildew (O. mangiferae) is the most destructive malady encountering almost all the commercial cultivars. In the present study total eight botanicals were tested against powdery mildew under field. Minimum powdery mildew severity (10.83 %) and maximum disease reduction (76.67 %) over control were recorded in treatment      with Neem leaf extract at 10 per cent concentration. The next best treatment was Garlic clove extract at 10 per cent concentration which was found on par with Onion bulb extract, Zinger clove extract and Turmeric rhizome extract in per cent disease severity and per cent disease reduction respectively

Abiotic stresses alter expression of S-Adenosylmethionine synthetase gene, polyamines and antioxidant activity in pigeon pea (Cajanus cajan L.)

Expression of S-Adenosylmethionine synthetase (SAMS) gene in pigeon pea (Cajanus cajan L.) was analyzed by qRT PCR during abiotic stresses viz., drought, heavy metal (CdCl2) and cold. Maximum expression of SAMS gene in the leaves were observed at 3 days after drought stress with 15% PEG. Conversely, its expression was not detected in leaves and roots at cadmium stress but transcripts were down regulated as compared to the control. After 6 days of stress expression of SAMS gene was increased in leaves and roots as compared to the control but it was lower than its expression at 3 days after stress. The activities of antioxidative enzymes like glutathione reductase, glutathione-s-transferase, ascorbate peroxidase and metabolite constituents like polyamines and glycine betaine were also analyzed. The activities of antioxidative enzymes and concentration of glycine betaine showed remarkable increase in response to all stresses, except ascorbate peroxidase in heavy metal stress.</jats:p