THE GROWTH, NICOTINE AND PHOSPHORUS CONTENT OF TOBACCO GROWN AT DIFFERENT SOIL TEMPERATURE, MOISTURE AND PHOSPHORUS LEVELS

Abstract

Growth, nicotine and phosphorus content of tobacco, as influenced by soil temperature, soil moisture and soil phosphorus levels, were investigated by growing the flue-cured variety Hicks in a combination of three soil temperature, four soil moisture, and three soil phosphorus treatments.Soil temperature of 22 °C. and soil moisture of 75 per cent of available moisture appeared to be the best for the over-all growth of tobacco. The over-all growth was a little lower at the 30 °C. soil temperature than at the 22 °C. temperature while at the 14 °C temperature it was very poor. Nicotine and phosphorus content in leaf tissue decreased with decreasing soil temperature. A decrease in soil moisture decreased the growth but increased the nicotine content of tobacco. Phosphorus content was influenced little by soil moisture treatments. Low soil moisture treatments were more detrimental to growth of tobacco at the low soil temperature than at the higher ones. Phosphorus produced growth responses at the low soil temperature only. Nicotine content was not influenced by soil phosphorus treatments. Phosphorus applications increased the leaf phosphorus content. At the 14 °C. soil temperature there was an increase in leaf and stalk weight and leaf area with added phosphorus while at the 22° and 30 °C. increases with soil temperature were very small. Stalk weights increased with increasing phosphorus applications at the higher but not at the lower soil moisture levels. The growth was decreased more at the soil temperature of 14 °C. and soil moisture treatments of 25, and near 0 per cent of available moisture than at the soil temperature of 22° and 30 °C. At the low soil moisture phosphorus applications decreased root growth while at the higher soil moisture treatments this phosphorus effect was reversed.