Identification of Races of Fusarium oxysporum f.sp. ciceris, Inciting Wilt of Chickpea in Andhra Pradesh and Parts of Telangana

Abstract

Background: Fusarium oxysporum f.sp. ciceris (Foc) is one of the most important pathogen, causing wilt of chickpea. It is soil and seed borne pathogen. A serious threat in Foc is the evolution of new races, which reduces exploitation of wilt resistance in the crop in a particular area. Eight races (race 0, 1A, 1B/C, 2, 3, 4, 5 and 6) were reported in the world and among them four races (race 1, 2, 3, 4) were from India. Race 1 was reported from Andhra Pradesh. It is very important to monitor the variation regularly in new isolates collected from different varieties or genotypes and different geographical regions to identify the racial pattern. Development of SCAR markers for identification of Foc isolates is also important as they are highly reliable. Methods: Twenty isolates of Fusarium oxysporum f.sp. ciceris were obtained from wilt infected plants of chickpea covering different places of Andhra Pradesh including two isolates from Telangana and confirmed the pathogen based on pathogenicity test. They were tested on host differentials of chickpea for races identification. Among these twenty isolates five most virulent isolates (Foc-6, Foc-10, Foc-12, Foc-17 and Foc-24) were selected for RAPD based on pathogenicity test and SCAR marker was developed based on DNA banding pattern during RAPD for one isolate.Result: Based on the disease reaction on differentials, concluded that 17 of them out of 20 were matched with race-1 reaction. Two isolates were matched with race-6 reaction and one is not matched with none of the races. An amplified product of polymorphic band of approximately 700 bp in the isolate Foc-12, obtained during RAPD analysis was selected for SCAR marker development and two SCAR markers were developed and validated. Identification of races mainly helps in development of resistant cultivars to specific races and might be contributed to development of integrated disease management practices for Fusarium wilt.

Biotic stress alleviating strategies in chickpea

“…are the major diseases of chickpeas (Rasool et al, 2015) Fusarium wilt (Fusarium oxysporum f. sp. ciceri): Using 10 chickpea lines as distinguishing factors,revealed the occurrence of four physiological races of F. oxysporum which are cicers in India (Ramanamma et al, 2020). Later, two further races (0-1) from Spain and another (race 6) from California were identified on the basis of variations in responsiveness on various host, Race 1 was subsequently split into two races, namely Race 1A (from India) and Race 1B/C (from Spain).…”