Myco-what?

Ten years ago the mention of mycorrhizal fungi to a golf superintendent might have met with a blank stare. Today’s managers are much more knowledgeable regarding the benefits of mycorrhizae. Research studies have shown us all how these specialized fungi can improve fertilizer utilization, rooting depth, the speed of establishment, disease and drought resistance of turf. 

The golf industry and golf managers take their responsibility for managing the game and the environment seriously. New tools, such as the use of beneficial mycorrhizal fungi, allow golf managers to improve the condition of both turf and soilGolf course management is a balance between the speed of play, golfer’s desire to see perfectly manicured turf grass and the ecological concerns of frequent chemical and water use. Golf courses do not operate in a vacuum but are part of a watershed. The selection of fertilizers, pesticides and water are important not only to the "look" of the course but to the surrounding environment as well. Golf course managers have a new tool in their belt that utilizes nature’s own way for growing plants and conserving resources. Golf course managers can use a group of beneficial soil organisms, the mycorrhizal fungi, to improve the health and vigor of their turf grass. 

Resistance to disease and nematodes.

Root pathogenic fungi and parasitic nematodes can be acute problems for golf course managers. Research indicates that the mycorrhizal relationship can improve grasses resistance to the negative effects of these organisms.  Mycorrhizal fungi improve the plants resistance to soil born diseases in several ways for a wide range of host species. The literature of recent years, indicates that mycorrhizal control of plant diseases may be strongly influenced by enhanced nutrition. Other factors might also play a role, such as less availability of resources for the pathogens, physical changes in roots and root tissues, chemical changes of root and plant tissues, reduction of environmental stresses, and increased concentrations of other beneficial soil organisms around roots. 

Root infections by pathogenic nematodes are generally less severe on mycorrhizal plants than on non mycorrhizal plants, but the responses may vary, and the mechanisms involved are being studied (Linderman 1992). Symptoms of nematode infection are generally reduced, and often, nematode populations themselves are reduced (Hussey and Roncadori 1978; 1982). One reasonable proposed mechanism is the improvement in turf grass vigor as a result of the mycorrhiza relationship masks yield losses caused by nematode infection. Also, changes in root exudates by mycorrhizae may change the attractiveness of roots to nematode pathogens. Increased production of inhibitory substances by mycorrhizae may additionally affect nematode population and survival. Research has demonstrated mycorrhizal fungal species Glomus mosseae and Glomus intraradices can help control the negative impacts of parasitic nematodes

When do I use mycorrhiza? And why would I want to?

Mycorrhizal inoculum should be incorporated both spring and fall for several years until healthy populations of mycorrhizae are established. Mycorrhizal colonization assessments are simple tests now available at many soil testing laboratories. Incorporating mycorrhizal inoculum during aerification is an appropriate way of developing a mycorrhizal network in the soil even for greens not inoculated during construction 

Mycorrhiza is an ancient and widespread form of symbiosis that takes place when specialized, soil- living fungi colonize plant roots, where they exchange nutrients like nitrogen (N) and phosphorus (P) in return of carbon sugars. Besides enhanced nutrient uptake, mycorrhizal relationships often provide additional benefits like increased resistance to drought, chilling, salinity and pathogens, to the host. In this context, the golf industry, which is challenged by the need to restrict inputs of fertilizers, pesticides and energy for irrigation and mechanical maintenance, is interested in utilizing these symbiotic associations to improve green quality in a more environmentally friendly and cost-effective way. Little is known about mycorrhizal colonization in turfgrasses, but since greens are believed to be generally poor in mycorrhizal forming fungi compared to natural soil habitats, there is focus on applying commercial inocula to ‘boost’ the extent of colonization in these plants.