The influence of biological and fungicidal seed treatments on chickpea (Cicer arietinum) damping off

Damping off of chickpea (Cicer arietinum) can lead to stand loss and yield reduction. Fungicide seed treatments are able to Successfully control chickpea damping off, but the effectiveness of many commercially available biological seed treatments has not been well tested. The objective of this study was to test the effect of commercially available biological and fungicide seed treatments on damping off of cultivars of kabuli and desi chickpea types. The biological seed treatments Bacillus pumilus GB34 (Yield Shield), Bacillus subtilis GB03 (Kodiak), B. subtilis MBI 600 (Subtilex), Streptomyces lydicus WYEC 108 (Actinovate), Streptomyces griseoviridis K61 (Mycostop), Trichoderma harzianum Rifai strain KRL-AG2 (T-22 Planter Box), the fungicide treatments fludioxonil (Maxim) and mefenoxam (Apron XL LS), as well as combined biological and fungicide seed treatments were tested in greenhouse and field experiments. The desi cultivar exhibited lower incidence of damping off in greenhouse and field trials than the kabuli cultivar. Several biological seed treatments inhibited germination and growth of the kabuli cultivar in the absence of pathogens in greenhouse experiments but not in field trials. In greenhouse experiments where soil was artificially infested with the damping off pathogen Pythium ultimum, the kabuli cultivar emergence was increased by the application of mefenoxam but not by biological seed treatments. Mefenoxam was the most effective seed treatment in field trials at three locations in Montana in the spring of 2007. Biological seed treatments were ineffective for reducing damping off and increasing plant growth measurements above untreated controls, even in combination with fungicides. These results indicate the use of mefenoxam is critical for controlling Pythium damping off in Montana and that biological seed treatments are not effective.