Management of chickpea wilt (fusarium oxysporum f.sp. ciceris) using trichoderma spp.

Thirty-eight Trichoderma isolates were collected from fields grown with chickpea in six districts of Northwestern Ethiopia in 2007 and 2008 and purified. Some isolates were identified to be Trichoderma harzianum, T. koningii and T. pseudokoningii. In in vitro tests the effect of Trichoderma isolates on colony growth of Fusarium oxysporum f.sp. ciceris and effect of seed treatment with Trichoderma isolates against chickpea wilt in glass house were studied at Amhara Region Agricultural Institute. In glasshouse experiment the treatments were arranged in randomized complete block design in three replications. Data on colony diameter in vitro tests and seedling emergence, wilt incidence, fresh and dry shoot weight in the glass house experiment were collected and were analyzed using the SAS system for windows V8 in ANOVA. In the in vitro tests Trichoderma isolates showed differences in their colony growth and antagonistic potential. Sixteen isolates showed competition potential, seventeen mycoparasitic and five lysis effects on F. oxysporum f.sp. ciceris. In glasshouse experiment, five Trichoderma isolates, two of which had shown mycroparasitic effect, two competition effect and one lysis effect were tested as seed treatment on two chickpea varieties namely Adet local and Shasho against fusarium wilt as compared with untreated control. Significant differences were observed among the treatments in reducing wilt incidence on Adet local and Shasho varieties. However, Shasho showed low levels of disease incidence compared to the Adet local. Lower incidence was recorded on Adet local with Trichoderma isolate Tr6 (mycoparasitic ability) and for Shasho with Trichodrema isolate Tr5 (competition ability), respectively. Significant differences were recorded in fresh and dry weight of shoots in the Trichoderma treated Adet local over the control. Trichoderma isolates improved the plant growth also. Highest fresh and dry shoot weight of Adet local was recorded with the isolate Tr3 (competition ability) followed by Tr6 (mycoparasitic). Significant differences were also recorded in fresh and dry shoot weight in the Trichoderma treated Shasho variety over the control. However the highest record was for Tr6 (mycoparasitic) followed by Tr7(mycoparasitic). The result showed that the potential of Trichoderma in reducing wilt incidence, delaying disease onset. Our study revealed that biological control agents such as Trichoderma can be a useful component of integrated chickpea fusarium wilt management and further study is also important under field conditions.