Management of Soil-borne Diseases of Onion with Selected Biological Control Agents and Soil Amendments
Ohio State University
E.B. Gergon-PhilRice,R. M. Gapasin-LSU, M. B. Brown-UPLB, L.E. Padua-UPLB, D.K.M. Donayre-LSU,M. M. Antolin-PhilRice, and S.A. MillerOhio State U
This study examined the effects of vesicular arbuscular mycorrhizae (VAM) alone, in combination with organic manures, and in comparison with other growth-promoting materials on root-knot and pink root diseases, growth, and yield of onion.
1. Determine the effects of vesicular arbuscular mycorrhizae (VAM) on root-knot and pink root diseases, growth, and yield of 'Yellow Granex' and 'Red Creole' onions at seeding and transplanting at two fertilizer levels under field conditions 2. Determine the effects of VAM applied singly or in combination with animal manure on root-knot and pink root diseases, growth and yield of Red Creole 3. Compare the effect of VAM with seed and root inoculants (Vital-N® and Bion®) on root-knot and pink root diseases, growth and yield of Red Creole at different times of application 4. Evaluate the effects of VAM applied alone or in combination with organic materials on root-knot nematode under microplot condition 5. Evaluate the efficacy of four Bacillus formulations for the control of M. graminicola in Yellow Granex onion under greenhouse conditions
VAM is an economical and environment-friendly supplement that could help reduce fertilizer inputs in onion production. It also helps onion plants tolerate infection from soil-borne pathogens such as root-knot nematode and Phoma. Combining VAM with chicken manure enhanced onion yield. VAM applied singly or in combination with organic material can significantly reduce number of galls and population of root-knot nematode,and enhance more growth and development of the plant. It can serve as good alternative management for M. graminicola which is more effective, economical and environmentally safe. 'Nemaguard' formulations B and C is a potential biocontrol agent that could reduce nematode density in the roots and surrounding soil when applied a week before nematode penetration.