RESISTANCE BETWEEN TURFGRASS SPECIES

A FUNGUS ENDOPHYTE ACREMONIUM COENOPHIALUM, COLONIZING PERENNIAL RYEGRASS SPECIES IN NATURE, CONFERS INSECT RESISTANCE UPON THE HOST PLANT AGAINST SEVERAL INSECT PREDATORS. THE FUNGUS PROPAGATES ITSELF BY COLONIZING THE SEED, WITHOUT HAVING ANY ADVERSE EFFECTS ON THE PLANT. THE OBJECTIVES OF THIS PROPOSAL ARE TO ISOLATE AND MASS PRODUCE THE ENDOPHYTE IN PURE CULTURE; TO STUDY THE NUTRITIONAL REQUIREMENTS OF THE FUNGUS; TO DEVELOP METHODS TO INFECT TURFGRASS SPECIES OF COMMERCIAL IMPORTANCE; TO CHECK IF THE ENDOPHYTE/GRASS ASSOCIATION ALSO EXHIBITS RESISTANCE TO FUNGUS PATHOGENS. A LARGE NUMBER OF ENDOPHYTE ISOLATES WILL BE COLLECTED AND MAINTAINED AS STOCK CULTURES. METHODS USING SURFACE INOCULATION IN DUAL CULTURE AND POT CULTURE AS WELL AS INJECTION INOCULATIONS WILL BE DEVELOPED TO INITIATE ENDOPHYTE COLONIZATION IN DIFFERENT GRASS SPECIES. IF THE PLANT BECOMES COLONIZED AND THE FUNGUS IS TRANSMITTED TO THE SEED THE PROGENY WILL BE TESTED FOR INSECT RESISTANCE AT A LATER TIME. PLANTS DERIVED FROM GRASS SEED THAT ALREADY CONTAIN THE ENDOPHYTE, WILL BE CHALLENGED WITH PATHOGENIC FUNGI TO DETERMINE IF COLONIZATION BY ENDOPHYTE ALSO CONFERS PROTECTION AGAINST FUNGAL PATHOGENS. IT IS ANTICIPATED THAT OTHER TURFGRASS SPECIES WILL BE COLONIZED BY THE ENDOPHYTE AND THAT THE INSECT RESISTANCE WILL BE TRANSFERRED TO THE NEWLY COLONIZED GRASS SPECIES.