STUDIES ON MORPHOLOGICAL, CULTURAL AND PATHOGENIC VARIABILITY AMONG THE ISOLATES OF FUSARIUM SPP. INCITING COWPEA WILT IN KERALA

  • SREEJA, S.J. DEPARTMENT OF PLANT PATHOLOGY, COLLEGE OF AGRICULTURE, KERALA AGRICULTURAL UNIVERSITY, VELLAYANI, TRIVANDRUM- 695522, KERALA, INDIA. Corresponding author’s e-mail: sreejasj@gmail.com
Keywords: Fusarium spp., Variability, Pathogenic, Morphological, Cultural, Cowpea.

Abstract

Twelve isolates of Fusarium spp., incitant of cowpea wilt were studied for their morphological, cultural and pathogenic variability. Among the isolates, F7, F8, F10 and F11 were non – pathogenic whereas all others were wilt producing type. The growth rate of the isolates varied from 0.86-1.42 cm/day. Macro conidia produced were falcate, fusoid to sub cylindrical, mostly 3-5 septate and the size ranged from 18.8-7.9 x 3.3-1.8 µm in size. Microconidia were oval to ellipsoidal, cylindrical, straight or curved. Intercalary and terminal chlamydospores were observed among the isolates.

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