Submitted to: Soil Biology and Biochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/29/1988
Publication Date: N/A
Interpretive Summary: Soilborne plant pathogens are major yield-limiting factors in the production of food, fiber and ornamental crops. Pythium seed rot and preemergence damping-off is one of the most important diseases of chickpea in the Pacific Northwest of the U.S. Although this disease can be controlled by seed treatment fungicides, interest in the use of biocontrol agents to suppress this disease has been stimulated by trends in agriculture toward greater sustainability, public concerns about hazards associated with the use of chemical pesticides, and the high cost of synthetic chemical pesticides. The purpose of this research was to test fluorescent Pseudomonas bacteria as chickpea seed treatments for control of Pythium and to compare the effectiveness of the bacteria to standard chemical seed treatments. The results demonstrated that the bacteria significantly controlled Pythium damping-off, and in some cases the level of control was as good as that provided by standard fungicides. Thus, biological control has good potential for use in the Pacific Northwest chickpea industry.
Technical Abstract: Seven strains of fluorescent pseudomonads were studies for their ability to suppress seed rot and preemergence damping- off of chickpea (Cicer arietinum) caused by Pythium ultimum in two naturally-infested soils in Eastern Washington. Seed treatment with two Pseudomonas fluorescens strains, Q29z-80 and M8z-80, increased emergence and yields of chickpeas as compared to nontreated controls in some but not all field trials at Central Ferry and Pullman, Wash., in 3 years of tests. In some trials, these seed treatments were equivalent to captan, metalaxyl or Penicillium oxalicum treatments. However, emergence and yields for the metalaxyl treatment were statistically equal or superior to all other treatments in all but one field trial.