Yield of Flue-Cured Tobacco and Levels of Soil Oxygen in Lysimeters with Different Water Table Depths1
- R. B. Campbell and
- G. T. Seaborn2
Flue-cured tobacco (Nicotiana tabacum L.) was grown in lysimeters with static water- table levels at $0, 45, 60, and 90 cm below the soil surface to more clearly define the level at which a favorable balance between soil aeration and water supply is attained. The oxygen and CO2 content of the soil air was determined periodically at various depths. Water-table treatment effects were evaluated in terms of root and shoot growth, yield, and quality of tobacco.
Dry leaf yields for the 90-, 60-, and 45-cm water-table treatments were all significantly (P≥0.05) greater than that for the 30-cm treatment. Yields for the 60- and 90- cm water-table levels were larger, but not significantly (P≥0.05) larger than the 45-cm treatment. The yield difference between the 60- and 90-cm treatments was not significant (P≥0.05). Roots of tobacco recovered from soil above the 60- and 90-cm water tables weighed only 10% more than roots recovered from soil above the 30- cm water table. Average CO2 and O2 gradients in the soil above the water table were nearly equal but of opposite sign. Soil environmental conditions imposed by the 60-cm water-table treatment of this study provided the most favorable balance between aeration and water supply for tobacco.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .