Freezing Sensitivity of Leaf Tissue of C4 Grasses

Eight C*4-photosynthetic pathway grasses were compared for freezing sensitivity and hardening ability. A temperature-gradient bar was used to freeze leaf samples, and the resulting damage was assessed by measuring electrical conductance of the electrolytes leached from injured tissues. Paspalum dilatatum and Eragrostis curvula were least sensitive to freezing and both exhibited considerable ability to harden. Setaria anceps cv. Narok and Digitavia sp. cv. Slenderstem were the most sensitive, and showed little or no ability to harden under the growing conditions used.