STUDIES ON BACTERIAL BLIGHT OF POMEGRANATE CAUSED BY Xanthomonas axonopodis pv. punicae (Hingorani and Singh) Vauterin et al.
KrishiKosh
View Archive InfoField | Value | |
Title |
STUDIES ON BACTERIAL BLIGHT OF POMEGRANATE CAUSED BY Xanthomonas axonopodis pv. punicae (Hingorani and Singh) Vauterin et al.
|
|
Creator |
KATWAL, VINAY SINGH
|
|
Contributor |
SHARMA, R.C.
|
|
Subject |
---
bacterial blight,pomegranate,Xanthomonas axonopodis pv. punicae |
|
Description |
ABSTRACT The present investigation entitled “Studies on bacterial blight of pomegranate caused by Xanthomonas axonopodis pv. punicae (Hingorani and Singh) Vauterin et al” was conducted in the laboratories of Department of Plant Pathology and experimental farm of Department of Fruit Science during the year 2012 to 2014. Considering the magnitude and losses due to bacterial blight in pomegranate, investigations were undertaken on cause of the disease, variability, epidemiological factors and management aspects. Survey revealed that disease was prevelant in nine districts of Himachal Pradesh with highest incidence and severity in Jachh in Kangra district. The bacterium was rod shaped, gram negative and non-spore forming. It was positive to starch hydrolysis, gelatin, liquefaction and H2S production. Yeast extract dextrose broth was found superior in supporting the growth of the pathogen at a temperature of 28±1oC with a pH range of 6.5. Study on 20 different bacterial isolates revealed variations in growth and colour in cultural studies, size in morphological and appearance of symptoms in pathogenic studies. The isolates exhibited 100 per cent polymorphism for OPA-2, OPB-1, OPF-7 and OPF-10 primers showing significant molecular variability. The infection rate increases as rainfall, temperature and relative humidity favours the disease development and spread, in 2012 and 2013 on both leaves and fruits. The AUDPC was maximum on leaves as compared to fruits in both the years. None of the tested weeds were found as collateral host of the pathogen. All the pomegranate germplasm was moderately to highly susceptible against the disease. Salicylic acid (100 ppm) was effective under pot and field conditions to reduce the disease severity. Pseudomonas fluorescens and cow urine (5%) were significantly effective in reducing the disease severity under in vitro, pot and field conditions. Clove oil, eucalyptus oil and neem oil reduced the disease severity under in vitro, pot and field conditions, respectively. Among chemicals streptocycline (100 ppm) and Bordeaux mixture 1% spray was very effective in reducing the disease severity under in vitro and field conditions. COC (0.25%) + streptocycline (0.01%) as paste treatment was highly effective in managing the disease. Application of Bordeaux mixture (1%) + bleaching powder (100g/plant) reduces the initial inoculum in the field. Pruning in the month of December and January reduces the disease severity to some extent. Application of NPK and multinutrients lowers severity of the disease under field conditions. The IDM strategy evaluated was found successful and feasible in managing the disease than individual treatments for disease control. |
|
Date |
2016-06-02T15:22:03Z
2016-06-02T15:22:03Z 2015 |
|
Type |
Thesis
|
|
Identifier |
http://krishikosh.egranth.ac.in/handle/1/66650
|
|
Language |
en
|
|
Format |
application/pdf
|
|