Studies on the Use of Fungal Plant Pathogens for Control of Hydrilla verticillata (L.f.) Royle
ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
Pagination or Media Count:
A survey was conducted in populations of Hydrilla verticillata L.f. Royle growing in lakes and rivers of the southeastern United States for the purpose of identifying plant pathogens with potential biocontrol use. An isolate of the fungus identified as Macrophomina phaseolina Tassi Goid. was collected from the foliage of hydrilla growing in Lake Houston, Texas. In repeated laboratory, greenhouse, and field tests, this fungus was pathogenic to hydrilla. Inoculum concentrations of between 10,000 and 1,000,000 colony forming units per milliliter were sufficient to kill hydrilla test plants over a 3- to 4-week period. In a field of 46 species and subspecific taxa within 22 families,this fungus was pathogenic only to hydrilla and duck lettuce Ottelia alismoides L. Pers.. This fungus may be useful as a biocontrol agent of hydrilla. Under severe infestations, hydrilla will impede navigation, clog drainage and irrigation canals, reduce recreation activity, and disrupt wildlife habitats.
- Agronomy, Horticulture and Aquiculture