Effect of Flower Bud Removal on Carbon Dioxide Exchange Rates of Cotton

Abstract

Numerous fruit removal studies have demonstrated that reproductive sink removal enhances cotton (Gossypium hirsutum L.) vegetative growth and development. Few studies, however, have examined changes in CO2 exchange rates accompanying fruit removal. The objective of this study was to establish the effect of early season flower bud removal on whole plant CO2 exchange rates of cotton. The effect of flower bud removal on the CO2 exchange rates of cotton was investigated in a 31-day study conducted in a controlled environment. Differences in net photosynthesis, dark respiration, daily carbon gain, and carbon use efficiency were not observed in this study with flower bud removal. However, the rate of increase (or decrease in dark respiration) for these parameters was greater with flower bud removal with their maxima occurring later in the study period. All selected photosynthetic parameters also increased steadily with time for both treatments.