Journal of Plant Pathology & Microbiology

Abstract

Efficacy of Water Extracts of Some Mangrove Plants for Eco-friendly Management of Root Rot Disease of Groundnut

Arjunan Muthukumar, Ramasamy Naveenkunar and Arjunan Venkatesh

Root rot of groundnut caused by Macrophomina phaseolina causes significant losses in groundnut growing areas of Tamil Nadu. Hence, the present study was conducted to assess the prevalence and incidence of dry root rot of groundnut in different district of Tamil Nadu, India during 2013-14, assess the cultural characters and pathogenic variability among the isolates of M. phaseolina and to test the antifungal activity of water extracts from mangrove plants against pathogen. The results revealed that the maximum root rot incidence was observed (30.33%) in Sivapuri village of (I3) Cuddalore district. The disease incidence was more in, VRI2 variety and incidence was found to be more in sandy loam soils. Regarding the cultural characteristics revealed that the isolates I2 and I3 significantly recorded the maximum (90 mm) mycelial growth of M. phaseolina and the isolate I3 was found to be more virulent when compared to other isolates tested. Water extracts of nine mangrove plant species were screened against the root rot pathogen, M. phaseolina. Of these, Salicornia brachiata (21.33 mm), Rhizophora apiculata (23.00 mm) and Suaeda maritima (26.33 mm) were found to be highly effective against the test pathogen