Sorghum growth and dry matter yield as influenced by soil water, bulk density and temperature

Abstract

The influence of soil moisture, bulk density and soil temperature on root and shoot dry matter yield of sorghum ( Sorghum vulgare ) grown for 30 days in pots using sandy loam soil (available P, 3 mg/kg) was studied at different levels of applied phosphorus. The increase in each level of soil moisture tension from 33 to 100 j/kg and to 500 j/kg significantly decreased both root and shoot dry matter yield of sorghum. Phosphorus application significantly increased both root and shoot dry matter. Increase in the bulk density of soil from 1400 to 1550 kg/m 3 significantly decreased the root dry matter. But further increase in bulk density to 1700 kg/m 3 significantly decreased both root and shoot dry matter. The adverse effect of higher soil moisture tension and bulk density was less pronounced at 100 mg/kg applied phosphorus. Increase in soil temperature from 25°C to 30°C significantly increased both shoot and root dry matter of sorghum, but further increase to 35°C drastically reduced the dry matter yield.