Evaluation of biological and chemical seed treatments to improve stand of snap bean across the southern United States

Thirteen bacterial, four fungal, and four chemical fungicide seed treatment s were evaluated one or more years in multiple field locations across the s outhern United States. Snap bean seed was treated in bulk with fungicides a nd most biocontrol agents, shipped to individual locations, and stored unti l planting or treated on site immediately before planting. Populations of b iocontrol agents on seeds were assayed after seed treatment and planting. A nalysis of variance of percent plant stand at 28 days after sowing revealed highly significant (P < 0.01) effects of location and treatment in 1996, 1 997 and 1998, A treatment by location interaction also occurred in 1996 and 1997. When treatments tested in two or three years were analyzed together, no biological seed treatments significantly affected percent stand. Carbox in significantly increased percent stand compared with nontreated seed in d ata sets combined from 1997 and 1998 and 1996 to 1998; captan and carboxin plus metalaxyl also increased stand in 1997 and 1998. Improvements in effic acy and consistency of biological seed treatments are necessary before they can be recommended for use in Snap bean production. (C) 2000 Elsevier Scie nce Ltd. All rights reserved.