An Evaluation of the Effectiveness of Some Fungicides in Controlling Chickpea Blight (Kermanshah Province)

Chickpea blight caused by Didymella rabiei is considered as the most important disease of chickpea in Kermanshah province. The disease is seed borne in addition to being persistent on infected residues, secondary infection taking place through pycnidiospores. In laboratory tests, the effects of six fungicides were tested at : 0.01, 0.1, 1.0, 10.0 and 100.0 ?g.a.i.ml-1 CSMA(Chickpea Seed Meal Agar) based on radial growth rate of four isolates of D. rabiei in a factorial test under a completely randomized design. The fungicides were captan, carbendazim, mancozeb, tridemorph, chlorotalonil and carboxin-thiram. For controlling the primary seed borne infections through seed treatment fungicides and a control of the secondary infections through chemical spray of the chickpea canopy, those fungicides were employed under field conditions. In the first year the naturally infected seeds and in the second year the artificially infested seeds were sown. The experimental design was a completely randomized block design of four replications. Mycelial growth of four isolates of D. rabiei were significantly inhibited on CSMA treated with any of the fungicides at 10 ?g.a.i.ml-1 .The most effective fungicide for a control of the mycelial growth of the pathogen under In Vitro conditions was carbendazim. Results showed that: in the field tests with naturally infected as well as artificially infested seeds, carbendazim and carboxin-thiram were significantly superior to the other fungicides for a control of the primary seed borne infection of the fungus. tridemorph (EC 75%) showed some phytotoxic effects on germination and seedling growth. Foliar sprays of chlorotalonil were significantly superior to those of other fungicides in controlling the secondary infection.