Effect of Environmental Stress on the Growth and Amounts and Forms of Phosphorus in Plants¹

Abstract

The effects of applied fertilizer P and soil‐water stress on the growth and amounts and forms of plant P were investigated to provide further information on the potential of plant material to contribute P to runoff. Cotton [Gossypium hirsutum (L.)], little bluestem (Andropogon scorparius Michx.), sorghum [sorghum sudanense (Piper) Stapf.], and soybean [Glycine max (L.) Merr.], plants were grown in the field on Durant loam, a member of the fine, montmorillonitic, thermic Vertic Argiustolls. Fertilizer P additions of 0, 50, 100, and 200 kg/ha were made and a water‐stress treatment initiated by applying only one‐third the amount of water lost as evapotranspiration. Plant growth and P content were determined at weekly intervals following plant emergence. Growth and total P content increased with an increase in applied fertilizer P for all plants except little bluestem. The total P and inorganic P content of the plants decreased gradually with growth. Inorganic P constituted the major proportion of plant P (approximately 80, 70, 70, and 80% for cotton, little bluestem, sorghum, and soybean, respectively), and remained constant during plant growth. A three‐fold reduction in soil‐water content (60‐fold increase in soil‐water suction) resulted in a decrease in plant growth and total and inorganic P content. The effect of the soil‐water stress was reduced by increases in applied fertilizer P. It was calculated, however, that the addition of fertilizer P was not a viable economic method of increasing crop yields to negate any drop in yield due to drought conditions.

Growth conditions impact 2,2-bis (p-chlorophenyl)-1,1-dichloroethylene (p,p′-DDE) accumulation byCucurbita pepo

“…The observed effect of soil moisture content on pollutant uptake was generally consistent with those seen by Sharpley and Reed (1982) and Angle et al (2003), who each noted a direct relationship between moisture content and the uptake of inorganic phosphate and metals, respectively, by plants. However, in the earlier studies, biomass increased with increasing moisture.…”

Cell membrane stability and leaf water relations as affected by phosphorus nutrition under water stress in maize

“…Phosphorus concentration in the leaf tissues increased with increasing P levels in both the treated plants and control and it was lower in the treated plants than in the control (data not presented), as in the results of cell sap analysis. Sharpley and Reed (1982) observed increased P concentrations in leaves, with increased application of P in cotton, sorghum (Sorghum sudanense Stapf.) and soybean (Glycine max L.).…”

“…The values of those parameters increased with increasing P level in both tlae treated plants and control (Table 5). Sharpley and Reed (1982) observed that the reduction of plant growth due to water stress was less pronounced when the plants received larger amounts of P fertilizer in cotton, sorghum, and soybean. The total plant dry weight increased at the highest P level (compared to the lowest P level) by 59.6, 97.2, and 115.5% in cultivars G-4578, K-8388, and P-3358, respectively, in the water stress treatment.…”

Freeze–Thaw Effects on Phosphorus Loss in Runoff from Manured and Catch‐Cropped Soils

“…The basis for this opinion is that catch crops concentrate P above ground, some of which may become available to runoff. Under field conditions, annual ryegrass, a common catch crop in northern agroecosystems, contains 1.7 to 7 kg ha −1 of total P (TP) (Ulén, 1997; Molteberg and Tangsveen, 2002), with 60 to 80% of plant P in inorganic form (Jones and Bromfield, 1969; Sharpley and Reed, 1982). Annual ryegrass contains more P than other less common catch crops, like white clover ( Trefolium repens L.) and fescue grass ( Festuca pratensis Huds.)…”