Vol. 10, Issue 6 (2021)

Author(s):
Sunna Deepti, Mudadla Hareesh and Dr. HC Lal

Abstract:
The present investigation was carried out in the research farm as well as laboratory of Birsa Agricultural University, Kanke, Ranchi on variability in Fusarium oxysporum f.sp. udum causing wilt of Pigeonpea and its management. The systematic investigation revealed that wilt disease in Pigeonpea was found to be infected with Fusarium oxysporum f.sp. udum at all ten locations surveyed in 2015-16 and 2016-17. Maximum wilt percentage was found at Bukru (32.14%) followed by Kanadu (29.40%) and Ranchi BAU (28.63%). After conducting elaborate survey at 10 locations, forty isolates were collected for studying variations among isolates characters. To identify Fusarium pathogen as it’s actual casual agent for the disease pathogenicity test was conducted by using different effective isolates (Isolate-1, 14, 35). It clearly revealed that Fusarium oxysporum f.sp. udum is the cause for wilt disease in Pigeonpea. Morphological studies of Fusarium oxysporum f.sp. udum revealed that the dimensions of macro condia, micro conidia and chlamydospores shows larger variations among different isolates. Among four liquid media, maximum and fastest mycelial growth was obtained in PDA medium followed by Richards medium, Czapeks medium, & Martins medium. In PDA liquid media isolate Fou-Ran-1 given maximum mycelial dry weight that is 470 mg. After in detailed study of all forty isolates regarding their cultural, morphological studies these isolates are grouped into different categories based on criteria like size of macro and micro conidia, septation of macro condia, their growing speed on different semi solid mediums and number of spores under 10x microscopic field.