Variability among the isolates of Fusarium spp. causing chickpea wilt in Maharashtra
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Author:V.K. MANDHARE, A. V. SURYAWANSHI AND B.M. JAMADAGNI
p-ISSN:0024-9602, e-ISSN:2582-5321, Vol:94, Issue:jan-jun
DOI: https://doi.org/10.29321/MAJ.10.100651
Abstract
Chickpea (Cicer arietinum L.) is one of
the major pulse crops grown in India and
other semi-arid regions of the world. Chickpea
is reported to be affected by more than 52
pathogens (Nene et al., 1984). Among these,
Fusarium oxysporum Schl. emend Snyd. Hans.
f. sp. ciceri (Padwick) Snyd. and Hans, is
a wide spread soil borne disease and is reported
from many parts of India with intensity ranging
from 10 to 100 per cent (Singh et al., 1986).
The chickpea varieties resistant to Fusarium
wilt is now becoming susceptible. It is,
therefore, necessary to see the pathogenic
variability so as to find out strategies for
management of Fusarium wilt. Chickpea plants
infected with Fusarium wilt were collected
from 66 locations in 19 districts of Maharashtra
at flowering to pod formation stage. Isolations
from infected roots were made on potato
dextrose agar. The isolates of Fusarium spp.
were identified (Booth, 1971; Padwick, 1940).
The isolates were categorized into different
groups based on morphological, cultural
characters and pathogenecity. Variations in the
growth of mycelium, colour / pigmentation
of mycelium and sporulation among the isolates
were recorded by growing on agar medium
(Om Gupta et al., 1986). The size of micro
and macro conidia were measured with the
help of binocular. Pathogenecity test on
chickpea cultivar JG 62 a highly susceptible
to Fusarium wilt was conducted by adapting
pot culture technique (Hawre and Nene, 1982).
For this purpose, the Fusarium isolates were
mass multiplied on sterilized crushed cotton
seed separately which was then mixed in the
sterilized soil (soil + FYM, 3:1) at the rate
of 1 kg Fusarium inoculum per 10 kg of
sterilized soil. It was kept for 15 days so
as to multiply. Water was given as and when
required. The earthen pots of 10 cm diameter
were filled with this wilt sick soil as per
the isolates. The seeds of highly susceptible
variety of chickpea i.e. JG 62 was sown in
the pots. Pot as well as water culture technique
(Nene et al., 1981, Cabrera, 1985) were adopted
for identification of highly pathogenic isolates
of Fusarium oxysporum f. sp. ciceri. The
experiment was undertaken in completely
randomized block design with five replications.
The observation on wilt incidence was recorded
at 30, 45 and 60 days after sowing in pot.
The soil temperature and soil moisture prevailed
during experimentation were in the range of
22-27oC and 12.5-20% respectively
Key words : Fusarium spp, Pathogens