Molecular Characterization of coat protein gene of Tospovirus isolate from vegetable cowpea and tomato (Record no. 289736)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 05021nam a22001577a 4500 |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 632.3 |
| Item number | NEE/MO |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Neeraja R |
| 245 ## - TITLE STATEMENT | |
| Title | Molecular Characterization of coat protein gene of Tospovirus isolate from vegetable cowpea and tomato |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc | Vellayani |
| Name of publisher, distributor, etc | Department of Plant Pathology, College of Agriculture |
| Date of publication, distribution, etc | 2022 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 131p. |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | MSc |
| 520 ## - SUMMARY, ETC. | |
| Abstract | The study entitled “Molecular characterization of coat protein gene of Tospovirus isolate from vegetable cowpea and tomato” was carried out at College of Agriculture, Vellayani during 2019-2021 with the objective of symptomatology, serological diagnosis and molecular characterization of Tospovirus causing necrosis disease in vegetable cowpea [Vigna unguiculata subsp. Sesquipedalis] and tomato [Lycopersicon esculentum Mill]. Plant samples showing the typical symptoms of Tospovirus were collected from two taluks of Thiruvananthapuram (Thiruvananthapuram and Chirayinkeezhu) district of Kerala during December to September, 2020-21. A higher incidence of Tospovirus (90%) on cowpea was recorded in Kalliyoor, in a commercial cowpea variety Badari. 100% disease incidence by Tospovirus was observed on tomato variety Vellayani Vijay at College of Agriculture, Vellayani. The study on the disease incidence (DI) of infected crops in most of the fields showed more than 25 per cent DI. From the study it was also observed that there is variation in disease severity with age of crops. Weed plants Ageratum conyzoides (F: Asteraceae) and Ludwigia perenis (F: Onagraceae) found to be associated with Tospovirus infection. The virus was sap transmissible and was maintained in local lesion host, Chenopodium amaranticolor and cowpea assay variety, Pusa Komal by mechanical inoculation using potassium phosphate buffer. In the present study virus was mechanically inoculated to different varieties of cowpea and tomato. Both mechanical as well as graft inoculation was tried in tomato varieties. From the mechanical inoculation studies, the vegetable cowpea variety Githika was tolerant compared to Lola and Vellayani Jyothika based on number of days taken for symptom development and nature of symptoms and among the bush varieties, Co-6 found to be tolerant. While in tomato, Variety Arka Rakshak found to be tolerant as compared to Vellayani Vijay and Manuprabha.Successful graft transmission of Tospovirus observed in tomato and it can be used as a reliable method for screening for disease resistance against Tospovirus in tomato. No seed transmission was recorded in Tospovirus isolate of cowpea and tomato and the seeds obtained from infected plants of tomato showed less germination percentage. The virus causing bud necrosis disease in cowpea and tomato was serologically detected using ELISA and DIBA and found that Tospovirus isolate from both cowpea and tomato showed close relationship with WSMoV. The virus was also detected using RT-PCR and an amplicon of size 1000bp was obtained using primer specific to coat protein of GBNV 207 and WSMoV. The studies on cross infectivity indicated possible transmission of Tospovirus isolate from cowpea to tomato and vice versa. Activity of defense related enzymes such as peroxidase, polyphenol oxidase and phenylalanine ammonia-lyase was more on inoculated plants than healthy control plants. The activity was higher in tolerant variety of cowpea (Co-6) and tomato (Arka Rakshak).The Protein and isozyme profile of both tolerant and susceptible cultivars of cowpea and tomato showed higher protein and isozyme production in tolerant varieties pointing towards a positive correlation of disease resistance to PR proteins and defense related enzymes. Thus the present study revealed disease incidence due to tospovirus on cowpea and tomato was more prevalent in Thiruvananthapuram (Thiruvananthapuram and Chirayinkeezhu Taluks) district of Kerala. The serological and molecular characterization of cowpea Tospovirus confirmed that virus belongs to serogroup IV which is Watermelon silver mottle orthotospovirus. One of the tomato sample reacted positive to Tospovirus of serogroup I which is Tomato spotted wilt virus indicating the presence of serogroup I and IV in tomato. Association of Tospovirus in symptomatic weed plants seen in fields of both cowpea and tomato can be positively correlated to the high disease severity in these areas. Mechanical inoculation, enzyme activity studies, SDS protein and isozyme profiling indicated that vegetable cowpea variety, Githika and tomato variety, Arka Rakshak have tolerance to Tospovirus infection. Hence on the basis of present investigation, it can be concluded that usage of tolerant genotypes like Githika in cowpea and Arka Rakshak in tomato along with management of weeds like Ageratum and Ludwigia can reduce the disease severity to some extent. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Plant Pathology |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Aisha R (Guide) |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Item type | Theses |
| Not for loan | Collection code | Permanent location | Current location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| Not For Loan | Reference Book | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2022-07-21 | 632.3 NEE/MO | 175399 | 2022-07-21 | Theses |