Cutting Edge: beer yeast biostimulants, updated nematode guide

Featured research includes a novel biostimulant and new info on nematode treatment.


Xunzhong Zhang, Ph.D.

Efficacy of decomposed yeast cell wall extract-based biostimulant, by-product of beer brewing, on physiological fitness and quality of creeping bentgrass under heat and drought stress

Creeping bentgrass (Agrostis stoloniferia) experiences quality decline during summer in the United States transition zone and other regions with a similar climate. Various bioproducts have been used to improve creeping bentgrass performance to mitigate the effects of summer stress. The yeast cell wall mainly consists of polysaccharides such as polymers of glucose (β-glucan) and polymers of mannose (mannoproteins), which are known to act as microbe- or pathogen-associated molecular patterns (MAMPs or PAMPs) and subsequently induce plant defense responses.

This growth chamber study was designed to investigate the effect of a decomposed yeast-cell-wall-based biostimulant made from a by-product of beer brewing on physiological fitness and quality of creeping bentgrass under heat and drought stress conditions. The biostimulant CW1+Fe+Mn was applied at 0.003 ounces per square foot (1 milliliter per square meter) weekly for 10 applications, and untreated grass served as the control. The treated grass was subjected to heat stress at 95/77 F (35/25 C) day/night and drought stress via deficit irrigation beginning 10 days after initial biostimulant application. Foliar application for CW1+Fe+Mn at 0.003 ounces per square foot weekly improved turf quality, photochemical efficiency, superoxide dismutase activity and proline content when compared to the control. In addition, the CW1+Fe+Mn treatment also increased root length, surface area, root volume and biomass relative to the control.

The results of this study suggest that foliar application of the decomposed yeast-cell-wall-based biostimulant could improve physiological adaptation, root growth and turf quality of creeping bentgrass under summer stress environments. 

— Xunzhong Zhang, Ph.D. (, Virginia Tech, Blacksburg, and Takashi Hamasaki, Calpis America Inc., Peachtree City, Ga.

golf course afflicted by nematodes

William T. Crow announces release of updated guide for nematodes

William T. Crow, Ph.D., University of Florida/Institute of Food and Agricultural Sciences professor of nematology, announced the release of an updated guide for nematodes for golf courses. “Nematode Management for Golf Courses in Florida” was originally published in January 2001 and has been updated several times since then.

“Golf contributes to the quality of life of many residents and visitors to the state of Florida and generates billions of dollars for our state economy. Some of the criteria that are used to designate a good course are ball speed and evenness of the playing surface and green healthy grass. Each of these quality parameters can be negatively affected by plant-parasitic nematodes,” says the introduction to the guide. “Of all the pests that commonly affect golf course turf in Florida, nematodes are probably the least understood and most difficult to manage. Nematode problems are more common and more severe in Florida than in most other states because our mild climate and sandy soils provide a perfect habitat for many of the most destructive nematode species.”

Sections of the guide include Plant-Parasitic Nematodes, Nematodes’ Effects on Turf, Symptoms of a Nematode Problem, Nematode Management Before Planting and others. Visit for the newest version of the guide.

Darrell J. Pehr ( is GCM’s science editor.