Abstract:
Basal stem rot (BSR) caused by basidiomycotina fungi, Ganoderma is one of the most
devastating diseases of numerous perennial, coniferous and palmaceous plants. In forest
systems, Ganoderma has an ecological role in the breakdown or delignificat ion of woody
plants. Symptoms of BSR disease can take several years to develop, and the presence of
the pathogen (such as indicated by fruiting bodies) is often only visible when the fungus is
well established and more than half of the bole tissue has been decayed, leaving no chance
for the grower to cure the infected palms. A limiting factor in controlling the BSR disease
is the lack of reliable diagnostic method(s) for early diagnosis. The present study was aimed
to evaluate the occurrence and incidence of basal stem rot disease and identify its causal
organism and to perform a bio-control based in-vitro management practices. The survey
study was conducted in three selected coastal districts viz. Patuakhali, Barishal and Pirojpur
during January 2018 to October 2019. The in-vitro management study was conducted in
Molecular Biology and Plant Virology Laboratory under the Department of Plant
Pathology, Sher-e-Bangla Agricultural University, Dhaka . The disease incidence of basal
stem rot was measured 69.33%, 68.33%, 57% and the disease severity was 36.89%,
30.79%, 29.5% in Pirojpur, Patuakhali and Barishal respectively. The highest disease
incidence (29.5%, 35.75% and 36.75%) was found in loamy soil, at 6 to 7 pH and in plant
age group 36-40 years respectively. In total 45 root samples, 14 sporophore and 12 disease
stem bits/barks were collected for aseptic isolation. Diseased root bits and sporocarp were
good source(s) for isolation of Ganoderma with Potato Dextrose Agar and Potato Sucrose
Agar that supported the highest radial growth and biomass production. The isolated
pathogens from root samples were identified as Ganoderma applanatum and Ganoderma
lucidum. The bio-control based management practices like Trichoderma suspension as bioagent,
Cattle urine as bio-product and Neem oil and Garlic extract as botanicals were
applied for controlling the basal stem rot disease studied under in-vitro condition. Among
the four bio-control agents cattle urine gave the best inhibitory actions against BSR disease
under in-vitro condition which accounted lower radial mycelial growth at 9 DAI of
Ganoderma (3 mm ) with 3 ml doses of application.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka,
In partial fulfillment of the requirements for
the degree of
MASTER OF SCIENCE
IN
PLANT PATHOLOGY