Phenotypic and molecular characterisation of phytophthora sp. inciting leaf fall of nutmeg (Record no. 142689)
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| fixed length control field | 05276nam a22002177a 4500 |
| 003 - CONTROL NUMBER IDENTIFIER | |
| control field | OSt |
| 005 - DATE AND TIME OF LATEST TRANSACTION | |
| control field | 20220422115352.0 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION | |
| fixed length control field | 220422b ||||| |||| 00| 0 eng d |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 632.3 |
| Item number | SUM/PH |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Sumbula V |
| 245 ## - TITLE STATEMENT | |
| Title | Phenotypic and molecular characterisation of phytophthora sp. inciting leaf fall of nutmeg |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc. | Vellanikkara |
| Name of publisher, distributor, etc. | Department of Plant Pathology, College of Horticulture |
| Date of publication, distribution, etc. | 2015 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | xxvi, 129 Pages |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | PhD |
| 520 3# - SUMMARY, ETC. | |
| Summary, etc. | The study on ‘Phenotypic and molecular characterisation of Phytophthora sp. inciting leaf fall of nutmeg’ was conducted in the Department of Plant Pathology, College of Horticulture,Vellanikkara during 2014-2015. The major objectives were to study the cultural, morphological and molecular characters and variability of different isolates of Phytophthora sp. associated with leaf fall of nutmeg and also to study the host range of the pathogen and to chalkout suitable management strategies Isolation of the pathogen from 18 samples from different locations revealed the association of the fungus, Phytophthora sp. and its pathogenicity was established under lab and in vivo conditions. Inoculation of the pathogen with culture disc on injured lower leaf surface showed early infection than that with zoospore suspension. Symptoms observed on leaves, shoot and fruits were almost same under both natural and artificial conditions. Variation in virulence was noticed among the isolates collected from different locations. The isolates, PPaL-1 and PPaF-17, from Parakkadavu, Thrissur and PSrL-10 from Sreemoolanagaram, Ernakulam were highly virulent. PKoL-2, the isolate from Kodissery was less virulent and other 14 were moderately virulent. Cultural and morphological characters of the isolates of pathogen were studied with different media viz. carrot agar, potato dextrose agar, oat meal agar, coconut water agar and V8 juice agar. Variation in cultural characters among the isolates was observed only in carrot agar and the variation in growth rate was noticed among the different media. Morphologically, mycelia of Phytophthora isolates from nutmeg were branched, coenocytic and hyaline and the sporangia were borne terminally /laterally on the sporangiophore in sympodial fashion, caducous, semi papillate, ovoid/elongated-ovoid/ellipsoid in shape with average size of 31.9-49.5 x 22.3 – 27.9 μm, L/B ratio of 1.4 – 1.8 and pedicel length of 10.21 – 20.24 μm. Early sporangial production was noticed in carrot agar and potato dextrose agar and the maximum count was in oat meal agar and carrot agar. Numerous chlamydospores were observed in all media. Comparison on the cultural and morphological characters of Phytophthora isolates of nutmeg with other Phytophthora spp. such as P. meadii, P. palmivora, P. capsici, P. colocasiae, P. citrophthora and P. ramorum revealed that, Phytophthora isolates from nutmeg could not be completely fitted into the phenotypic description of any of these known Phytophthora species. However, they showed some similarity to P. meadii, P. colocasiae and P. ramorum. In molecular characterisation, out of 18 isolates of nutmeg Phytophthora, 15 showed maximum homology with P. colocasiae and three viz. PPoL-3, PMaL-4 and PVaL-15 with P. meadii. Isolates PPaL-1, PKoL-2, PVeL-5, PKtL-6, PKaL-7, PMtL-8, PThL-9, PTuL-11, PKnL -12, PPaF-17 and PMoF-18 also showed homology with P. citrophthora and PMaL-4 and PSrL-10 with P. botryosa. Host range of Phytophthora isolate of nutmeg includes, rubber, vanilla, rose, Coreopsis, Eucalyptus and Citrus. Nutmeg is also a host of P. meadii of vanilla and P. citrophthora of Citrus and non host of P. palmivora, P. capsici, P. colocasiae, P. meadii of arecanut, rubber and cardamom. Rose is also found to be a host of P. meadii isolates of arecanut, rubber, cardamom, vanilla and P.citrophthora of Citrus. The cultural, morphological and molecular characters, host range and cross infectivity studies of various Phytophthora isolates could not revealed the exact identity of these isolates, as the distinguishing features overlapped among the various Phytophthora species. In vitro evaluation of chemicals / bioagents showed complete inhibition of the pathogen with 1% Bordeaux mixture, copper hydroxide (2g/l), copper oxychloride (2.5g/l), potassium phosphonate (3ml/l), combination fungicides, iprovalicarb + propineb (1.5 and 2.0g/l), cymoxanil + mancozeb (2g/l) and Trichoderma viride -1, T. harzianum and T. viride -2, the isolates from nutmeg and the reference cultures viz. T. viride (KAU) and T. harzianum (IISR). In in vivo experiment, all treatments were superior to control of which, spraying of 1% Bordeaux mixture + soil drenching of copper hydroxide (2g/l) and spraying of 1% Bordeaux mixture and soil application of T. viride showed maximum reduction of the disease. In addition, spraying and drenching of copper hydroxide and copper oxychloride were also found equally effective. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Plant Pathology |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | molecular characterisation of phytophthora sp. inciting leaf fall of nutmeg |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Sally K Mathew (Guide) |
| 856 ## - ELECTRONIC LOCATION AND ACCESS | |
| Uniform Resource Identifier | http://krishikosh.egranth.ac.in/handle/1/5810029638 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Koha item type | Theses |
| Withdrawn status | Lost status | Damaged status | Not for loan | Collection code | Permanent Location | Current Location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Price effective from | Koha item type |
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| Not For Loan | Reference Book | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2016-04-11 | 632.3 SUM/PH | 173619 | 2016-04-11 | 2016-04-11 | Theses |