| An investigation was conducted to study the effect of: different oxygen levels on cotton seed respiration and germination, interaction between carbon dioxide and oxygen on germination and radicle elongation, and soil moisture tension on soil gaseous composition and seed germination.;Seeds germinated for 48 hours were subjected to various levels of oxygen for 48 hours while their respiration and radicle elongation were monitored. A computer-controlled oxygen monitoring and control system that continuously provided respiration data was designed and successfully utilized in this experiment. Concentrations below 15% produced significantly shorter radicles and slower respiration rates. But even at 2.5% oxygen the reduction in mean radicle length, compared to the 21% O;The next experiment consisted of germinating cotton seeds in different mixtures of oxygen and carbon dioxide. Radicle elongation was much more responsive to variations in the oxygen concentration than in carbon dioxide. At oxygen levels below 5% there was pratically no germination, regardless of the CO;Three days after wetting the soil in a soil column, O... |
