Light Requirement for Emergence of Turf-Type Bermudagrass Seed.

In the transition zone, improved cultivars of seeded bermudagrass (Cynodon dactylon) are becoming increasingly popular.  Recent studies suggest that competition for light can significantly reduce germination, but there has been limited work on the light requirements for emergence of seeded bermudagrass. The objective of the present study was to determine how reduced light affected germination and emergence of three bermudagrass cultivars, including Transcontinental, Riviera, and SR-5994.  Twenty-five seeds of each of the three cultivars were planted into two-inch diameter plastic pots and placed in a growth chamber set to either 15 or 30 °C.  Three different types of shade cloth (30, 60, and 90% shade) were placed on top of each pot to reduce light, and were compared to a non-shaded control. Emergence of seedlings was monitored for a 3-wk period to determine the effects of shading on germination and emergence at the two temperatures. Shade significantly reduced the emergence of all cultivars at both temperatures. However, the emergence of Transcontinental was greatly inhibited by shade, especially at the lower temperature.