Freezing tolerance and nonstructural carbohydrate composition of carpetgrass (Axonopus affinis chase)

Abstract

An experiment to determine the nonstructural carbohydrate composition and nodal survival (LT50) of common carpetgrass was conducted between 1993 and 1994 at Baton Rouge, La. Nonstructural carbohydrates in stolons were primarily sucrose [70-130 mg · g-1 dry weight (DW)] and starch (8-33 mg · g-1 DW). Total nonstructural carbohydrate (TNC) composition of stolons ranged between 30 to 165 mg · g-1 DW. Node survival following exposure to 2 °C ranged from 0% in August-sampled grass to 48% in December. The LT50 following acclimation under field conditions was -2 to -4 °C. Environmental factors influenced nonstructural carbohydrate composition, partitioning, and node survival. No relationship between TNC concentration and low-temperature tolerance was found. This research confirms previous reports that low-temperature tolerance of carpetgrass is very poor, and its culture may be limited to geographical areas having moderate winter temperatures.