Survival and management of Colletotrichum gloeosporioides (Penz. & Sacc.) causing mango anthracnose (Mangifera indica L.)
Loading...
Date
2017
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
Mango anthracnose caused by Colletotrichum gloeosporioides (Penz. & Sacc.) is a very
serious fungal disease and causes substantial yield losses in mango cultivars. The present investigations
were carried out on survival and viability of C. gloeosporioides fungus, evaluation of different
inoculation methods for disease development and evaluation of fungicides and botanicals for their
efficacy. The efficacy of urea was tested under in vitro conditions; urea was found effective in
inhibition of mycelial growth up to 72.8 per cent at 5% concentration. The pathogen survived for seven
month in soil as conidia or mycelium in infected debris under adverse conditions. As the depth and
duration increased, there has been a decrease in viability of the fungus indicating its long survival on
the soil surface only. The fungus could not survive at 5 cm depth after seven months of burial in
comparison to 81.6 per cent survival at same depth after one month of burial. At 5 cm and 10 cm depth
conidia or mycelium remained viable for five months at 2% urea concentration, however, fungus
remained viable up to four months at 5% urea concentrations. The fungus invaded the host tissues
through the injured as well as intact surface of leaves and fruits showing clearly its pathogenic ability.
The disease symptoms appeared on mango leaves and fruits after 36 hours of pin prick inoculation
method at 25±1˚ C. Out of five fungicides tested in vitro, carbendazim completely inhibited mycelial
growth up to 100% at 100 ppm concentration. Propiconazole at 500 ppm, while mancozeb at 1000 ppm
concentration inhibited mycelial growth up to 100%. Among botanicals eucalyptus leaf extract was
found most effective in inhibition of mycelial growth up to 70.4 per cent at 10 per cent concentration.
Under field conditions, two foliar spray with carbendazim @ 0.1% at 15 and 30 days after inoculation
disease was found most effective in controlling disease up to 71.43% and 65.22 per cent in cv. Langra
and Dashehari, respectively. Two foliar sprays with eucalyptus leaf extract @ 10% at 15 and 30 days
after inoculation was also found effective in reducing the disease severity over untreated control.
Description
Keywords
null