Pathogenic and morphological variability among Fusarium oxysporum f. sp. ciceri isolates causing wilt in chickpea

Abstract

Twelve Fusarium oxysporum f. sp. ciceri isolates were isolated from chickpea infected samples collected across different states of India. Pathogenic variability of twelve isolates was observed on seven chickpea cultivars viz., JG 62, Annigeri-1, Chaffa, CPS-1, K 850, L 550 and DCP 92-3. Among the twelve isolates APFOC-1 showed lowest wilt incidence 71.43 per cent and the isolate MPFOC-9 showed 100 per cent wilt incidence in all cultivars. The variability in morphological characters like size, shape, color of conidia and size, shape, color of chlamydospore were observed in all the isolates. The size of macroconidia varied from 9.23X2.53 ìm (WBFOC-12) to 19.3X5.52 ìm (MHFOC-8) with 2-4 septation. The size of microconidia varied from 4.4X2.93 ìm (MPFOC-9) to 8.26X4.2 ìm (MHFOC-8) with 0-1 septation. Macroconidia were sickle shaped and blunt ends with hyaline color. Microconidia were round to oval with hyaline color. Size of chlamydospore varied from 2.67 (UPFOC-11) to 8.24 (JKFOC-5). Chlamydospores did not show much variation with respect to shape and color. Based on the total number of spores observed per microscopic field, the twelve isolates categorized into four groups viz., poor sporulants, moderate sporulants, good sporulants and very good sporulants.