Abstract:
Three experiments were conducted to investigate the diseases of gladiolus in
Jashore, Dhaka and Manikganj districts of Bangladesh during February 2019 to
May 2019. Eighteen villages from 4 Unions of Jhikorgacha Upazila of Jashore,
two villages from Savar upazila of Dhaka and two villages from Singair upazila of
Manikganj district were selected for investigation. The disease incidence and
severity were recorded under natural epiphytic conditions. Seven diseases were
identified from cultivated gladiolus in Bangladesh viz. leaf spot, leaf blight, stem
rot, corm rot, flower rot, aster yellow and mosaic diseases. The identified causal
organisms for leaf spot, leaf blight and flower rot disease are Curvularia trifolii,
Botrytis gladiolorum and Curvularia lunata, respectively. However, stem rot and
corm rot diseases are caused by Fusarium oxysporum f. sp. gladioli. Mycoplasma
caused aster yellow and virus caused mosaic diseases of gladiolus were recorded
in the field of Jashore. The incidence and severity of diseases varied significantly
among the locations. In leaf spot disease, Incidence and severity varied
significantly from 22% to 72.67% and 2.67 % to 15%, respectively. In case of
leaf blight disease, the highest disease incidence and severity were recorded in
Dhalipara, Jashore that were 77.33% and 11.67%, respectively. Severity of stem
rot was observed highest in Nirbashkhola (11%) and the lowest in Baisha village
(2.67%). Disease incidence was varied from 10.67% to 25.33% for corm rot
disease. Incidence of flower rot disease varied significantly from 5.33% to 10%.
In case of Aster yellow disease, the highest disease incidence (9.333%) was
recorded in Mathuapara and Godkhali villages. The mosaic disease of gladiolus
was found only in Sharifpur village of Jhikargacha union of Jashore. The disease
incidence and disease severity were 3.33% and 20%, respectively. Farmer’s saved
corms of gladiolus were collected from Dhaka, Manikganj and Jashore districts
and health status was also investigated by modified blotter paper method in this
study. Five fungi viz. Fusarium oxysporum, Aspergillus flavus, Aspergillus niger,
Rhizopus stolonifer, Chaetomium sp. were isolated and identified from corm of
gladiolus. Apart from this, a survey was carried out on the socio-economic status
of gladiolus farmers and problem related gladiolus cultivation in Bangladesh.
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
