Soil-borne pathogen new to chickpea growing regions in India detected
File photo of Dr Mamta Sharma and her team at work in the pathogen lab. Photo: S Punna, ICRISAT
A soil-borne pathogen, new to chickpea growing regions in India, was detected during a real-time survey being conducted regularly to study the spike in soil-borne diseases. After intensive morphological and molecular characterization, the pathogen was identified as Ectophoma multirostrata – which to the best of our knowledge, this is the first report of E. multirostrata causing root rot of chickpea worldwide. The sequence of this new pathogen was submitted to the National Center for Biotechnology Information GenBank database and the findings were published in Plant Disease , a leading international journal for rapid reporting of research on new, emerging, and established plant disease.
Infected chickpea samples were collected from 300 different fields in five states — Madhya Pradesh, Maharashtra, Andhra Pradesh, Telangana, and Karnataka — spanning a diverse range of climates. An average incidence of soil-borne pathogens in the surveyed tracts was 25-30%. Of the 150 symptomatic root samples, most of the fungal colonies obtained were identified as Macrophomina phaseolina (syn. Rhizoctonia bataticola) causing dry root rot in chickpea, while isolations from 10-15% samples recurrently yielded the new pathogen closely resembling Macrophomina phaseolina.
Previous reports of E. multirostrata causing root rot were from Australia in coriander. Studies are underway to examine if this new pathogen has a climate change aspect to it. Since the disease symptoms are very similar to dry root rot and hard to differentiate visually, molecular characterization is needed for identification.
Due to soil-borne nature of this pathogen, field practices like deep summer ploughing, cultivation of alternative crops and soil solarization can reduce this disease severity to some extent.
The ongoing survey in major chickpea growing states in India is being conducted under the aegis of the Department of Science and Technology, Government of India and the Center of Excellence on Climate Change Research for Plant Protection in partnership with National Agricultural Research Systems.
This work was undertaken as part of the CRP Grain Legumes and Dryland Cereals (CRP-GLDC)
(L-R) Root Rot Symptoms, Pycnidia on host tissue and colony containing conidia. Photo: ICRISAT
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