Oral Technical Session: Disease Diagnosis and Detection

8-O

SCAR assay as a versatile diagnostic tool for detection of Macrophomina phaseolina in cluster bean.
A. CHAUDHURY (1)
(1) Department of Bio & Nano Technology, GJUS&T Hisar, Hisar, India

Macrophomina phaseolina is an opportunistic phytopathogenic fungus infecting major food, fiber, legume crops species including cluster bean, cotton, okra, soybean, rice in Africa, Australia, Brazil, India, North and South America; parts of Europe. Incidence of Charcoal rot results in significant yield loses and decline in galactomanan gum production in an industrially important crop cluster bean. Traditional culture-based and morphometric approaches are often time consuming, laborious and require extensive knowledge of classical taxonomy. Rapid detection tool is a prerequisite to decipher the in depth understanding of pathogenesis and disease management strategies for controlling infestation. Limitations have lead to development of alternative molecular approaches with improved accuracy and reproducibility such as SCAR as a diagnostic tool. 82 isolates from cluster bean and a range of other host plants habituating wide eco-geographic locations of India were employed for RAPD. Conspicuous RAPD monomorphic fragments specific to Macrophomina phaseolina were sequenced in order to develop SCAR diagnostic tool. Consensus sequences from selective RAPD markers were employed for designing SCAR. Results of SCAR diagnostic tool were validated and found to be highly reproducible and the diagnostic tool was very rapid and inexpensive. This is the first report for cluster bean and work clearly demonstrates that SCAR can readily be applied for detection of Macrophomina phaseolina.