INVESTIGATION AND SURVEY ON DISEASES OF MARIGOLD (Tagetes spp.) IN JASHORE DISTRICT OF BANGLADESH

Abstract

Three experiments were conducted for investigation and survey on diseases of marigold in 2019 at Jashore district of Bangladesh. Forty eight marigold fields of sixteen villages from four unions of Jhikargacha upazila were investigated for field diseases of marigold. The disease incidence and severity were recorded under natural epiphytic conditions. Seven diseases were recorded and identified in field conditions viz. leaf spot, botrytis blight, flower bud rot, stem rot, foliage blight, white mold, foot and root rot caused by Alternaria alternata, Botrytis cinerea, Alternaria dianthi, Fusarium oxysporum, Curvularia lunata, Sclerotinia sclerotiorum, respectively. However causal organism of foot and root rot was not identified. The incidence and severity of diseases of marigold varied significantly among the locations. In leaf spot disease, incidence and severity ranged from 30% to 54.33% and 9.33% to 18%, respectively. For Botrytis blight, disease incidence and severity were from 15.33% to 38.33% and 6.67% to 21%, respectively. However, incidence and severity of flower bud rot ranged from 12% to 40.66% and 6.03% to 18%, respectively. Moreover, incidence and severity of foliage blight were from 5.67% to 42% and 1% to 18%, respectively. The highest incidence and severity of stem rot disease were recorded in Nirbashkhola village (29% and 13%), respectively. In case of foot and root rot, the highest incidence and severity were recorded in Chandpur village (29.67% and 13%). Moreover the highest incidence and severity of white mold disease were recorded in Shiorda and these were 26.67% and 10.67%, respectively. Depending on the amount of disease, the major diseases of marigold were leaf spot, botrytis blight, foliage blight and flower bud rot. Farmer’s saved seeds were collected from Dhaka and Jashore districts and seed health status was investigated by blotter method following rules of ISTA. Five fungi viz. Fusarium oxysporum, Alternaria alternata, Aspergillus flavus, Aspergillus niger and Rhizopus stolonifer were isolated and identified from seed of marigold. Apart from this, a survey was carried out on the socio-economic status of marigold farmers and problems related to marigold cultivation in Bangladesh. Altogether, 48 farmers were interviewed in Jashore district of Bangladesh. Among the farmers, 91.67% were male and 8.33 % were female. As per farmer’s opinion leaf spot, botrytis blight, foliage blight and flower bud rot were major diseases of marigold.