Abstract
The objective of this investigation was to determine the diffusion coefficients of phosphorus in soils and relate the diffusion coefficients to the uptake of phosphorus by sorghum plants grown on the same soils. Four soils, namely Miller, Norwood, and two intergrades of Norwood and Miller were used. All four soils are calcareous and have about the same pH. These soils differ mainly on the basis of texture. The clay percentages are 12.5, 25.0, 36.0 and 59.0 for the Norwood soil, Intergrade I, Intergrade II and the Miller soil, respectively. The following determinations were made: (i) The diffusion coefficients of P in the soils; (ii) The uptake of P by sorghum plants grown for a period of thirty days; (iii) Solution P concentration in the soils; and (iv) The labile P in the soils. The four levels of P used were 0, 25, 50 and 100 ppm. The three moisture levels used were 100, 60 and 35% of available water at field capacity. The P uptake by sorghum plants increased with increasing additions of P and water, and with increasing clay content of the soil. No significant difference was found between uptakes from Intergrades I and II. The regression of P uptake on applied P, clay, and water 2 content was significant beyond 1% giving an R² value of 0.91. ...
Mahtab, Samuel Kallan (1969). Plant uptake vs. diffusion of phosphorus as related to texture, applied P and water content of soil. Doctoral dissertation, Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -174761.