Study on Survival and Infectivity of Faba Bean Gall (Olpidium Viciae Kusano)in Ethiopia

Abstract

Among biotic factors that attributed for low yield of faba bea, faba bean gall caused by Olpidium viciae was the newly emerged constraints of production in most faba bean growing in the country. This study was intended: to determine growth requirement, to research out survival and infectivity of faba bean gall through time. The enquiry was carried out for two consecutive years 2018 and 2019. Soil and stubble samples were collected from heavily faba bean gall infected field. Soil sample was stored dry at 4°C and residue samples was stored dry at room temperature after pulverized until the experiment has been started. The experiment was arranged in randomized complete block design with 3 replications. Treatments were evaluated to estimate the infectivity of soil and stubble infected with faba bean gall at 4 months intervals in greenhouse with the period of 4, 8,12,16,20 and 24 months after inoculum collection. Results showed that the significant variation observed between treatments and control check along with experimental time. Significantly (p≤0.05) mean maximum incidence and severity 76.67% and 23.33 recorded on infected debris followed by infected soil 40% and 20%, respectively while minimum was noted on sterilized soil with disease free seeds (control) in the first experimental time, four months after inoculum collection. In the last experimental time, 24 months after inoculum collection, the mean maximum 26.7 observed on faba bean stubble whereas the lowest 0% severity was recorded on the control. Faba bean gall might survived in infected soil and stubble up to two years. The extension of this work to know the exact pathogen remaining time in the soil, inquiry that would be answered the question whether this pathogen is air borne or not and development of management option in major growing areas were suggested.