Plant adaptation to heat stress may involve changes in C allocation within the plant. The objective of this study was to determine whether heat tolerance of C3 perennial grass species was associated with the alteration of C allocation to proteins and lipids under heat stress. We study the patterns of allocation of newly fixed C through photosynthesis to proteins and lipids of heat-tolerant thermal Agrostis scabra Willd. and heat-sensitive creeping bent grass (A. stolonifera L. ‘Penncross’) exposed to high soil temperatures at 37°C or control temperature at 20°C. The allocation patterns of newly fixed C during heat stress into proteins and lipids in various plant organs (shoots, crowns, and roots) were examined using the14CO2 pulsechase labeling technique. High soil temperature reduced the allocation of newly fixed C into proteins and lipids in shoots and roots, resulting in a lower protein and lipid content than control plants for both grass species. The decline in the protein and lipid content and the decrease in the14C allocation were less pronounced in thermal A. scabra than in A. stolonifera. The more efficient incorporation of newly fixed14C into lipids and proteins could support the superior tolerance of thermal A. scabra to prolonged periods of high soil temperatures.
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science