Follow
International Journal of Current Microbiology and Applied Sciences (IJCMAS)
IJCMAS is now DOI (CrossRef) registered Research Journal. The DOIs are assigned to all published IJCMAS Articles.
Index Copernicus ICI Journals Master List 2018 - IJCMAS--ICV 2018: 95.39 For more details click here
National Academy of Agricultural Sciences (NAAS) : NAAS Score: *5.38 (2020) [Effective from January 1, 2020]For more details click here

Login as a Reviewer

Indexed in



National Academy of Agricultural Sciences (NAAS)
NAAS Score: *5.38 (2019)
[Effective from January 1, 2019]
For more details click here

ICV 2018: 95.39
Index Copernicus ICI Journals Master List 2017 - IJCMAS--ICV 2018: 95.39
For more details click here

See Guidelines to Authors
Current Issues

Original Research Articles

PRINT ISSN : 2319-7692
Online ISSN : 2319-7706
Issues : 12 per year
Publisher : Excellent Publishers
Email : editorijcmas@gmail.com / submit@ijcmas.com
Editor-in-chief: Dr.M.Prakash
Index Copernicus ICV 2018: 95.39
NAAS RATING 2020: 5.38

Int.J.Curr.Microbiol.App.Sci.2018.7(4): 3478-3493
DOI: https://doi.org/10.20546/ijcmas.2018.704.394


Morphological and Molecular Characterization of Alternaria Isolates Causing Purple Blotch Disease of Onion
B.S. Chethana1*, Girija Ganeshan2, Archana S. Rao2 and K. Bellishree2
1AICRP, ZARS, VC Farm, Mandya, University of Agricultural Sciences,Bangalore, Karnataka, India
2Division of Plant Pathology, Indian Institute of Horticultural Research, Hessaraghatta Lake PO, Bangalore, Karnataka, India
*Corresponding author
Abstract:

Purple blotch is the most destructive disease commonly prevailing in almost all onion growing pockets except in very cool production areas of the world. The present study was carried out to understand the diversity in Alternaria population causing purple blotch disease of onion. Out of fifty six geographical Alternaria isolates of Karnataka seventeen were selected as descriptive isolates based on morphological characteristics for understanding the genetic variability. The isolates exhibited Ash, Ashy black, Ashy white, Ashy green and blackish green colour. Sabouraud dextrose agar supported the maximum growth whereas corn meal agar did not support the growth. Asthana Hawker’s medium supported the sporulation of the isolates. The isolates showed variability in shape, conidia length, width, beak length and number of septa. Sequencing and blasting of nucleotide sequence of ITS region of ribosomal DNA of isolates revealed 100% matching with five different species of Alternaria viz., A. porri, A. alternata, A. tenuissima, A. palandui and A. brassicicola. Cluster analysis of ITS rDNA sequences did not provide reliable differentiation between the species and among the isolates. The results put forward that ITS region of ribosomal DNA is inappropriate for taxonomic resolution of Alternaria species infecting onion.


Keywords: Onion, Purple blotch, Alternaria, Morphological, Molecular characterization, Diversity
Download this article as Download

How to cite this article:

Chethana, B.S., Girija Ganeshan, Archana S. Rao and Bellishree, K. 2018. Morphological and Molecular Characterization of Alternaria Isolates Causing Purple Blotch Disease of Onion.Int.J.Curr.Microbiol.App.Sci. 7(4): 3478-3493. doi: https://doi.org/10.20546/ijcmas.2018.704.394