Response of Chickpea (Cicer arietinum L.) Genotypes against Collar Rot Disease Caused by Sclerotium rolfsii Sacc.

Abstract

Aims: Collar rot is a fast spreading and destructive disease and is becoming more serious at seedling stage causing rot at collar region especially in area where paddy based cropping system is followed. Lack of sources of resistant in present cultivar against Sclerotium rolfsii cause serious threat to chickpea production. Therefore, the present study was carried out to evaluate the chickpea genotypes against S. rolfsii to the identification of resistant sources for further breeding program.
 Study Design: Randomized Block Design (RBD) with two replications were used.
 Place and Duration of Study: Regional Rice Research Station, Navsari Agricultural University, Vyara, between October 2019 to April 2020.
 Methodology: Pathogen was isolated from infected collar region of chickpea plant by directly transfer of sclerotia and infected bits on potato dextrose agar (PDA) medium. After purification, pathogen was identified by observed the colony character and sclerotia formation. The morphological characters viz., mycelial growth and mycelial characteristic were studied under high power magnification (40X) and sclerotia formation, shape and colour were studied under low power magnification (10X) from 10 days old culture. 39 chickpea genotypes were used for the studies. A field experiment was conducted during Rabi -2019-20 season. The inoculum was thoroughly broadcasted in soil @ 10g/ row. Germination per cent and disease incidence were observed.
 Results: Chickpea (Cicer arietinum L.) collar rot disease caused by Sclerotium rolfsii Sacc. was exhibited initial white fluffy mycelium appearance on potato dextrose agar medium. Microscopic view of mycelium was hyaline, branching, compact with septate and had a clamp connection. White sclerotia were formed after 4th days of incubation and later within 10 days after incubation it became mature and colour changed from brown to dark brown. Sclerotia appeared shiny due to presence of gummy material. Out of 39 chickpea genotypes only five viz., GJG-1713, GG-6, GJG-1509, Phule Vikram and JGK-1 were identified as moderate resistant against collar rot disease caused by S. rolfsii under inoculums inoculated rice fellow cropping system.
 Conclusion: Chickpea genotypes viz., GJG-1713, GG-6, GJG-1509, Phule Vikram and JGK-1 were showed moderate resistant reaction against collar rot disease caused by S. rolfsii.