Analysis of diversity of Phytophthora species prevalent on some common economically important crops through morphological and molecular methods.
Journal of Mycopathological Research ; 2007 [Vol.1] Pages:-
Abstract
Phytophthora, an oömycetous organism with ~70 recognized species, is one of the most destructive of plant pathogens affecting a wide host range consisting of economically important crops having a widespread occurrence in the wet tropical regions; and as a result, almost a third of the Phytophthora species reported worldwide are from India. Identification and taxonomy of Phytophthora is still acknowledged to be 'difficult' primarily due to its morphological plasticity. An attempt was made, therefore, to identify and characterize the Phytophthora population prevalent on some of the common high value economically important crops grown in this region; brinjal [aubergine], betel vine (Piper betle), guava, sesame, roselle, chilli (Capsicum annuum), black pepper (Piper nigrum), pointed gourd [Trichosanthes dioica] and taro [Colocasia esculenta] both through molecular methods such as restriction fragment length polymorphism of the internal transcribed spacer (ITS) region of rDNA, sequencing of the ITS region and also morphological parameters. The Phytophthora species prevalent on these crops, which were identified by these mentioned molecular methods, were P. melonis, P. nicotianae, P. colocasiae and P. capsici. Multiple occurrences of different Phytophthora species on a single crop were also observed. Data on all of the mentioned aspects of the isolates, twenty-six in number, under accession at the World Phytophthora Collection, USA, are discussed.
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