Crop Responses to Elevated Carbon Dioxide and Interactions with Temperature

Abstract

SUMMARY Carbon dioxide concentration [CO2] and temperature are major environmental factors that affect plant growth, development and yield. Increases in [CO2] above present levels will improve productivity of cotton crop because of improved carbon exchange rates, vegetative growth and number of reproductive organs (bolls). In contrast, increase in temperatures above optimum decrease cotton yield due to increased boll abscission and smaller boll size. Doubling of [CO2] did not ameliorate the adverse effects of high temperature on reproductive growth (boll abscission or boll size) or fiber quality. Thus, it is concluded that in future climates, if increases in [CO2] are associated with higher temperatures, cotton yield and quality will decrease particularly in regions where present temperature are near to optimum.