Abstract
‘Diamond’, a new zoysiagrass [Zoyski mmrella (L.) Merr.] cultivar released from the Texas Agricultural Experimental Station, is noted for its fine texture and excellent density. To better define the utilization of this new turfgrass, more information is needed on the responses of ‘Diamond’ to variable shade levels. Greenhouse and field studies were conducted to evaluate ‘Diamond’ turf responses under different light intensities. In the greenhouse, ‘Diamond’ zoysiagrass was grown for 6 weeks under four shade treatments ranging from 30% to 90% shade levels. Soil temperature was maintained between 26° and 28°C. Turf under 30% and 60% shade had the highest turf establishment rate, as indicated by turf quality and color. Root mass and number decreased with increasing shade levels. In the field, the effects of light intensity on turf quality, carbohydrate status, and winter survival of ‘Diamond’ were examined during the growing seasons in 1995 and 1996. Well-established turf was subjected to four shade treatments (0, 47%, 73%, and 87% shade). Acceptable turf quality was obtained up to 73% shade. Shading resulted in increased clipping yield and linearly reduced total nonstructural carbohydrate (TNC) content. However, relatively stable TNC levels were maintained under 47% shade after an initial decline. Decreased TNC may have contributed to a significant reduction in winter survival of shaded ‘Diamond’ zoysiagrass observed in the field.