Survey of Rhizome Rot and Wilt Disease Incidence of Ginger in Major Growing Area of Darjeeling Hill, India

Abstract

Ginger production in major growing areas of Darjeeling hills, West Bengal, India during recent years has suffered tremendously. As it is annual crop and needs very less care with high economic return, it is popular among low income group of farmers. Rhizome rot disease caused by fungi (Pythium spp., and Fusarium oxyporium f. sp. zingiberi) and bacteria [Pseudomonas (Ralstonia) solanacearum] are the major problems all over ginger growing areas of India. The main reason being the occurrence of disease having complex etiology and so far a very little work has been done in this regards. The basic information viz. quantification of disease incidence in the region, symptoms type and its distribution, cropping patterns and other agronomic practices, time of initiation of the disease etc. The key information for formulating effective management strategies are lacking. So, a survey was undertaken during the year 2005 and 2006 in ginger growing area to gather the basic information as well as to collect plant and soil samples from ginger fields for further study. About 80-84 % of the plots suffered from the disease severely during both 2005 and 2006 ginger growing season. From the survey, it was observed that June- July was the most vulnerable period for initiation and spread of the disease and the less incidence of the disease were noticed if the disease initiates after the second fortnight of July. Further, it was also observed that more than 3-4 years crop rotation coupled with cultivation of buckwheat, coarse cereals and cruciferous crops as preceding crop was found to be a better option for management of rhizome rot and wilt disease complex of ginger.