Management of bacterial wilt of ginger incited by Pseudomonas solanacearum (Smith) smith
Loading...
Files
Date
1994
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Plant Pathology, College of Horticulture, Vellanikkara
Abstract
Bacterial wilt is one of the most destructive disease of ginger in Kerala. The pathogen was isolated from wilted ginger plant and its pathogenicity established. The isolate of bacterium was characterized and identified as Pseudomonas solanacearum (Smith) Smith based on its morphological, cultural, biochemical and physiological characters coupled with its pathogenicity.
Invitro inhibitory effect of antibiotics, fungicides, botanicals and others against p. solanacearum was tested. Ambistryn- S and chloromycetin 1000 ppm exhibited maximum inhibition of bacterium. Of the two fungicides tested Bordeaux mixture one per cent gave maximum inhibition of the bacterium. Among the botanicals and others tested, water extract of ocimum spp. And garlic at 50 g/1 exhibited maximum inhibition of the bacterium.
Field experiment on the management of bacterial wilt of ginger revealed that none of the treatments gave an absolute control of the disease. However, plots treated with Ambistryn- S and Bordeaux mixture had minimum wilt incidence than the other treatments. The changes in the total rhizosphere microflora and the pathogen P. solanacearum as a result of treatments in field codition were assessed. Ambistryn- S, Bordeaux mixture and chloromycetin had effectively reduced the population of P. solanacearum. Ambistryn- S, Bordeaux mixture, Streptocycline and chloromycetin had reduced the bacterial population. The maximum reduction of fungal population was observed in Bordeaux mixture and Ambistryn-S treated plots. Actinomycetes population was minimum in plots treated with garlic. Results of the study on the in vitro effect of treatments on the soil microflora and the pathogen P. solanacearum revealed that Ambistryn-S and Bordeaux mixture had effectively reduced the P. solanacearum. There was a maximum reduction of bacterial population was recorded in soil treated with Ambistryn-S, Streptocycline, Bordeaux mixture, Chloromycetin and Terramycin. The soil treated with Bordeaux mixture and calixin had minimum count of fungal population. Ambistryn-S, streptocycline and water extract of Ocimum spp. Treated soils had minimum count of actinomycetes.
The result of the pot culture study on the management of bacterial wilt of ginger revealed that plants treated with Bordeaux mixture, Ambistryn-S, Terramycin and Chloromycetin had minimum wilt incidence.
Correlation studies were made between environmental factors and wilt incidence. There was a positive correlation between maximum air and soil temperature and wilt incidence. The colonization of VA-mycorrhiza was greater in roots of healthy plants than the roots of infected plants. The incidence of phyllosticta leaf spot was minimum in plants treated with Bordeaux mixture, Ambistryn-S, Calixin and Chloromycetin both in pot culture and field experiments.
The effect of treatments on plant height, number of tillers and yield were also recorded. Bordeaux mixture and Ambistryn-S treated plants had maximum plant height, more number of tillers and better yield than the other treatments.
Thus the present study revealed that one per cent Bordeaux mixture can be used as a prophylactic measure to reduce the incidence of bacterial wilt of ginger. The use of water extracts of botanicals for the control of the disease needs further detailed investigations.
Description
PG
Keywords
null
Citation
170706