Identification and Characterization of resistance against downy mildew in Pumpkin (Cucurbita moschata L.) and Snapmelon (Cucumis melo L. var. momordica )

dc.contributor.advisorSekhon, Parvinder Singh
dc.contributor.authorKhanal, Sita
dc.date.accessioned2017-09-29T14:18:21Z
dc.date.available2017-09-29T14:18:21Z
dc.date.issued2017
dc.description.abstractPseudoperonospora cubensis [(Berk and Curtis) Rostovez] an obligate parasite causing downy mildew of snapmelon and pumpkin, that can survive and reproduce on living host tissue resulting in significant yield losses. Fourty six and thirty three accessions of snapmelon and pumpkin were screened against P. cubensis in year 2015-2016 and 2016-2017 cropping season respectively. Plants were inoculated at optimum level of sporangial suspension (4.0 x 104 sporangia per ml) to create downy mildew. Out of fourty six accessions of snapmelon, three were resistant having incidence in the range of 20-30 per cent and rest were moderately resistant, moderately susceptible, susceptible and highly susceptible. However, in case of pumpkin, thirteen accessions were resistant having incidence in the range of 3-6 per cent and rest were moderately resistant, moderately susceptible, susceptible and highly susceptible. Significant mean maximum disease index was observed in snapmelon accession SM 2013-7 and minimum in accession MC 2013-4. Similarly, in case of pumpkin, mean maximum disease index was observed in accession BN 364 and minimum in accession P-111. Antioxidant enzymes activity was estimated spectrophotometrically from the leaf samples. The data pertaining to the activity of antioxidant enzymes revealed significant differences among the accessions showing different reaction against P. cubensis. Higher activity of antioxidant enzymes were observed in resistant followed by moderately resistant accessions whereas; activity gradually declined among susceptible and highly susceptible accessions of snapmelon and pumpkin. Negative correlation was obtained between antioxidant enzyme activity and disease development suggesting possible involvement of these enzymes in imparting disease resistance against downy mildew in sanpmelon and pumpkin. Improving the genetic resistance of snapmelon and pumpkin to downy mildew through introgressive breeding could be an effective way to control this disease. The narrow genetic base of modern snapmelon and pumpkin accessions and a few sources of resistance make downy mildew resistance an important objective in snapmelon and pumpkin breeding programs. Therefore, the identification of new sources of resistance is desirable.en_US
dc.identifier.urihttp://krishikosh.egranth.ac.in/handle/1/5810031980
dc.keywordsPseudoperonospora cubensis, snapmelon, pumpkin, downy mildew, resistance, antioxidant, Cucurbita moschata L., Cucumis melo L. var. momordicaen_US
dc.language.isoenen_US
dc.pages74en_US
dc.publisherPunjab Agricultural University, Ludhianaen_US
dc.research.problemIdentification and Characterization of resistance against downy mildew in Pumpkin (Cucurbita moschata L.) and Snapmelon (Cucumis melo L. var. momordica )en_US
dc.subPlant Pathologyen_US
dc.subjectnullen_US
dc.themedowny mildew in Pumpkin and Snapmelonen_US
dc.these.typeM.Scen_US
dc.titleIdentification and Characterization of resistance against downy mildew in Pumpkin (Cucurbita moschata L.) and Snapmelon (Cucumis melo L. var. momordica )en_US
dc.typeThesisen_US
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Sita Final Thesis CD.pdf
Size:
1.72 MB
Format:
Adobe Portable Document Format
Description:
M.Sc.
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Collections