The relative cold hardiness of 8 bermudagrass Cynodon sp. and 2 Paspalum vaginatum Sw. cultivars was evaluated in growth chamber by dry weight of regrowth obtained from these turfgrasses. Samples of the turfgrasses which were cold stressed in the field were taken into the greenhouse at regular intervals from fall through winter to spring. The degree of injury of samples subjected to low temperature in the laboratory was estimated via conductivity measurements. The field study related closely to laboratory analyses. There were significant differences between cultivars with respect to cold hardiness. The bermudagrasses appear to be more cold hardy than P. vaginatum cultivars. Of the turfgrasses studied, Brookings appears to be the most cold hardy followed by NEJC, Tifgreen, Pee Dee 102, Tifdwarf, LaJunta, Santa Ana, Tifway, Futurf and Adalayd in decreasing order of cold hardiness. All the cultivars tested were chilling sensitive, but Santa Ana and Tifway were less so than the other grasses tested. The results of the field and chilling injury tests suggest that Brookings is photoperiod sensitive and that it breaks dormancy later than the other cultivars tested.

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