Plant Pathology & Plant Biotechnology and Organic Farming, Biodynamics

Biography

Biography: Dr. Dariusz P Malinowski

Abstract

Many cool-season grass species have evolved with asexual, nonsymptomatic fungal endophytes of the genus Epichloë (formerly Neotyphodium) of the family Clavicipitaceae. These mutualistic associations have dramatic effects on grass host chemistry, increasing the resistance of symbiotic grasses to abiotic (drought, soil mineral imbalance) and biotic (vertebrate and invertebrate herbivory, nematodes, plant pathogens, plant competition) stresses. Native endophyte strains produce a range of bioprotective alkaloid and other non-alkaloid secondary compounds, several of them known to have detrimental effects on grazing animals. In the past two decades, epichloid endophyte strains have been selected with marginal or no capacity of producing ergot and/or lolitrem alkaloids. These novel endophyte strains have been introduced to several grass cultivars with the idea to increase grass host resistance to abiotic stresses without affecting grazing livestock, and abiotic stresses to ensure the high competitive ability of symbiotic grass cultivars. This new technology is known as “Symbiotically Modified Organisms” (SMO). A number of forage grass cultivars, including tall fescue (Lolium arundinaceum syn. Festuca arundinacea) and perennial ryegrass (L. perenne), have been inoculated with novel epichloid endophytes and commercialized in the USA and New Zealand. These SMO grass cultivars have been proven superior to cultivars infected with native epichloid endophytes in terms of grazing animal performance.