Abstract:
ABSTRACT
Powdery mildew of bottle gourd is one of the important disease responsible for lower
yield of bottle gourd in many countries. Management of powdery mildew disease is
required to maintain the quality and quantity of the fruit. Different management
approaches have been led to control the disease. In this experiment, we evaluated
silica and salicylic acid-based fungicide, Peak Performance Nutrient (PPN),
Potassium silicate, Phosphorus silicate and sulphur-based fungicide (McSulphur 80
WP) against control. The experiment was conducted from November 2019 to May
2020. BARI Lau-4 variety was selected for the present experiment. In the present
POinvestigation the highest reduction of disease incidence (36.89%) was recorded by
the application of potassium silicate (T₂). The nearest reduction of disease incidence
was found in Peak Performance Nutrient (T₅) (24.18%) followed by Silica (T₁)
(20.49%) and Phosphorus silicate (T₃) (20.08%). At 107 days after transplanting, the
PDI (Percent Disease Index) values were observed and it was found that the
maximum PDI was calculated from the control (64.17%). At 107 DAT, potassium
silicate (T₂) showed the highest performance (60.52%) in reduction of disease
severity. The second highest reduction of disease severity was recorded in case of
Peak Performance Nutrient (T₅) (38.06%) followed by Silica (T₁) (31.82%),
Phosphorus silicate (T₃) (30.74%), McSulphur 80 WP (T₆) (21.04%) and Salicylic
acid (T₄) (3.90%). The maximum number of fruit (10.00) was recorded from
application of potassium silicate (T₂) followed by McSulphur 80 WP (T₆) (9.67) and
Silica (T₁) (8.33). In case of weight, the maximum average weight of bottle gourd
fruit (2.52 kg) was recorded from application of potassium silicate (T₂) followed by
McSulphur 80 WP (T₆) (1.99), Phosphorus silicate (T₃) (1.87 kg) and Peak
Performance Nutrient (T₅) (1.85). Potassium silicate (K₂SiO₃) was found effective
against powdery mildew disease of bottle gourd. It also gave the best result in giving
large sized and heaviest fruits. Potassium silicate may be used as an alternative of
‘sulphur containing fungicide’.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfilment of the requirements
for the degree of
MASTER OF SCIENCE (M.S.)
IN
PLANT PATHOLOGY
SEMESTER: JANUARY–JUNE, 2021
