Morphological variations in Alternaria spp. isolated from different parts of Indian mustard entries

Abstract

A comparative study of conidia and conidiophores of Alternaria brassicae and A. brassisicola on the basis of mean morphology and per cent frequency was done in fourteen entries of Indian mustard namely, NDYR32, NDRE8-16, NDRS2010, PRB2004-3, Ashirwad, NDRE8213, NDR8501, NDRE4, NDYR8, JD6, NDRE7, NDRE22, NDRE2011 and Varuna. Both the species i.e. A. brassicae and A. brassicicola were isolated from infected leaves, stems and pods. A. brassicae and A. brassicicola isolates obtained from leaves, stem and pods showed variability in colony diameter, size of conidiophores and conidia, septation in conidiophores and conidia. On mean basis, the maximum colony diameter of 35.00 mm in NDRE8-16 and 35.33 mm in NDRE4 were noted with A. brassiceae and A. brassicicola isolates, respectively. The maximum length (160.45 mm) and width (21.48 mm) were noted in Ashirwad with conidia of A. brassicae as compared to A. brassicicola isolate. In conidia, higher number of transverse (15.00) and longitudinal septa (4.00) and maximum per cent frequency (73.33) were also recorded in Ashirwad with A. brassicae while in case of conidiophores, the maximum number of septa (7.00) found in Ashirwad and NDR8501.