Abstract:
A filed experiment was conducted in central farm of Sher-e-Bangla Agricultural
University and lab experiment was conducted for multiplication of selected bioagent
in lab of Department of Plant Pathology, Sher-e-Bangla Agricultural
University, Dhaka during the period from July, 2020 to June, 2021. The study was
carried out to evaluate the suppressive effects of selected endospheric bio-agents
viz. Trichoderma harzianum, Trichoderma viride, Metarizium anisopliae,
Verticilium lecanii, Bauveria bassiana and botanicals namely Neem, Nishinda,
Bhat and Lantana leaf extracts for management of Pepper leaf curl virus (PeLCV).
In response to different selected treatments, percent disease incidence and disease
severity on the basis of visible symptoms, analysis of chlorophyll contain in
diseases and healthy leaves, yield and yield attributes were recorded. An
encouraging performances was observed in reducing the disease intensity in terms
of plant infection and appearance the visible symptoms in leaves in comparison
to manage at 25, 55, 85 days after transplanting (DAT) which was after 7 days of
treatments application. Among the selected endospheric bio-agents, the lowest
disease incidence and severity was found in T
7
(Verticilium lecanii) treatment
followed by T
9
(Bauveria) and the highest in T
6
(T. viride) treatment. Among the
selected botanicals, the lowest disease incidence and severity was found in T
1
(Neem leaf extract) and the highest was found in T
4
(Lantana leaf extract). The
chlorophyll contain was tested based on visible symptoms in the field conditions.
From the results, it was found that among the treatments, the highest chlorophyll
contain was recorded in T
4
treatment (Lantana, 2.23 X 10
-03
and 5.52 X 10
) and
the lowest chlorophyll contain in T
1
treatment (Neem, 0.51 X 10
-03
03
) in case of both types of samples. The effect of different treatments on yield and
yield contributing characters also studied and significance variation was observed.
From the findings of the present study, it may be concluded that bio-agent,
Verticilium lecanii or Bauveria and botanical, Neem or Bhat leaf extracts can be
used as ecofriendly approach for management of Pepper leaf curl virus (PeCLV).
However, further investigation is needed to justify the present findings.
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
