Chemical and genetic control of the Fusarium species complex in chickpea and their effects on stand establishment under highland subtropical conditions

Abstract

Chickpea (Cicer arietinum L.) crop is seriously affected by a range of soil-borne diseases in many production areas around the world. Fusarium oxysporum f. sp. ciceris (FOC) and isolates of the Fusarium solani complex are the two most important groups of soil-borne pathogens of chickpea, causing damping-off, collar and root rots as well as vascular wilt. Seed treatments with fungicides and the use of cultivars with genetic resistance are the two most important strategies for the management of these pathogens in chickpea. Seeds of the Fusarium-susceptible cultivar ‘Cicero’ were treated with the following fungicides: Carbendazim, Carbendazim + Thiram, Captan, Iprodione, Iprodione + Thiram, Metalaxyl-M + Fludioxonil, Pencycuron, Procymidone, and Tolylfluanid. Seedling emergence and physiological seed quality were employed as evaluation criteria in field assays conducted under natural infestation of FOC and F. solani. The seed treatments with best overall results were Tolylfluanid and Captan. In a second assay, 41 accessions of the International Center for Agricultural Research in Dry Areas (ICARDA, Aleppo - Syria) were evaluated in a field naturally infested with FOC under a central pivot irrigation system. The accession ‘ILC 1929’ was employed as the susceptible control. There were significant differences among accessions regarding the collar root incidence (frequency of symptomatic plants). The inbred line ‘35C FLIP03’ displayed the stand with the largest number of healthy plants and had the highest yield plot(‑1 )(418 g), confirming its wide spectrum resistance to FOC isolates. The genotype ‘WR 315’ was highly susceptible, producing 61 g plot(‑1). The line ‘35C FLIP03’ might represent a very important genetic material for the development of FOC resistant cultivars combined with adaptation to tropical and subtropical regions of Brazil.