Development of an organic muskmelon production system against bacterial wilt disease

Bacterial wilt in muskmelons (Cucumis melo) is caused by Erwinia tracheiphila, which is vectored primarily by spotted (Diabrotica undecimpunctata) and striped (Acalymma vittata) cucumber beetles. Organic production field trials conducted at the University of Kentucky Horticultural Research Farm in Lexington, Kentucky in 2008, 2009 and 2010 identified a method utilizing spun-bonded row covers for beetle exclusion that increased productivity despite insect and bacterial wilt pressure. The seven treatments included (1) control-no treatment, (2) organic standard, row covers over plots until anthesis, uncovered until harvest, organic pesticides applied weekly, (3) row covers over plots until anthesis, uncovered for two weeks, recovered until harvest, organic pesticides applied weekly during two weeks open, (4) row covers over plots throughout season, Bombus impatiens under cover for pollination, (5) plots uncovered throughout season, organic pesticides applied weekly, (6) row covers over plots throughout season, row ends uncovered for two weeks for natural pollinator access, and (7) row covers over plots until anthesis, uncovered for one week, recovered until harvest, organic pesticides applied weekly. Removing the row covers for two weeks and then replacing them until harvest (Treatment 3) reduced potential bacterial wilt infections and provided yields similar to removal at anthesis followed by insecticide application (Treatment 2). Treatment 3 had a lower overall cost due to reduced insecticide application.