Cultural, Morphological and Molecular Characterization of Fusarium verticillioides causing Maize Ear Rot under Punjab Condition

Abstract

Maize ear rot caused by F. verticillioides which is prevalent on maize under Punjab conditions. The symptoms appear as white-pink fungal growth and causes “starburst” pattern of white streaks on the kernels. Thirty Fusarium isolates were isolated from the infected maize plant from different agro-chemical zones of Punjab. They are characterized on the basis of morphological, cultural characters and growth rate on Potato dextrose agar (PDA). The isolates produced micro-conidial 4.0-33.0 µm x 2.4-3.3 µm on PDA and macrocondia of 37.0-55.0 µm x 4.0-4.2 µm on Carnation leaf agar (CLA). Formation of sporodochia was observed on the Carnation leaf agar (CLA). The production of chalmydospores was not observed in any of the isolates. Isolates were grouped into three categories based on colony color and conidial size. The micro-conidial chains production was also observed on water agar infused with 0.2 perent KCl. Genomic DNA was extracted and was subjected to Polymerase chain reaction (PCR) by using species specific primers (PRO 1 PRO2, VER 1 VER2, VERT 1 VERT 2 and SUB1 SUB2). Out of thirty 27 isolates were confirmed as F. verticillioides as they gave single amplicon of 800 bp with primer pair VERT 1 & VERT 2 specific for F. verticillioides.