Plants phosphorus

W. C. Plaxton, Metabolic aspects of phosphate starvation in plants. Phosphorus in Plant Biology Regulatory Roles in Molecular, Cellular, Organi.smic, and Eco.sy.s-lein Proces.ses (J. P. Lynch and J. Deikman eds.), American Society of Plant Physiologists, 1998, p. 229. 

Brandon AM, Mikkelsen DS. 1979. Phosphorus transformations in alternately flooded California soils. I. Cause of plant phosphorus deficiency in rice rotation crops and correction methods. Soil Science Society of America Journal 43 989-994. 

Phosphorus containing fertilizers Phosphates are the basic substances in these fertilizers. Phosphorus is also essential for plants. Phosphorus compounds are produced by powdering rock phosphate and adding sulfuric acid to it. The resulting products - phosphoric acid and calcium salts (from the rock) are directly applied to the soil to increase its phosphorus content. Potassium fertilizers examples Potassium chloride, Potassium nitrate etc. A complete fertilizer contains nitrogen, phosphorus and potassium in a fixed ratio. This is called NPK fertilizer. 

Phytase offers significant promise as a means to reduce phosphorus levels in animal waste by 30-35%, while also reducing the cost of phosphorus supplementation. The enzyme hydrolyzes phytate (myo-inositol hexakisphosphate), the primary storage form of phosphorus in plant seeds and pollen, in several steps into inositol and inorganic phosphorus, which is readily bioavailable to the farm animals. Phytases can also have non-specific phosphorus monoester activity. Addition of phytases to farm animals diets significantly enhances bioavailability of plant phosphorus for the animals while reducing phosphorus in the waste and simultaneously allowing a reduction of total phosphoms in the feed 500 units of phytase... 

Phosphorus in the form of phosphate is the principal source of P for plants. Phosphorus is commonly applied in fertilisers although its uptake by plants is much less than that of N and K and its availability is one of the most common nutritional limitations to crop yield (Bould etal., 1983). Some of the P in soils and soil solutions may be present in organic compounds. However, it is unlikely to be available to plants in its organic form and decomposition of organic matter releases P in its available... 

From Sec. 2 it can be concluded that, due to the highly weathered state and high phosphorus sorption capacity of many moist tropical forests soils, the level of readily plant available phosphorus is low. Discussion on whether this means that phosphorus availability actually limits productivity of moist tropical forests is reserved until Sec. 4.1. Here we limit our concerns to a discussion of the phosphorus cycle in moist tropical forests and methods by which plant phosphorus acciuisition can occur in environments characterized by low levels of available P. The main aim of this section is to cjuantify the amounts and annual input/output fluxes of P for leaves, branches, boles, and roots of moist tropical vegetation. The inputs of phosphorus into moist tropical forests from rock weathering and wet and dry deposition, as well as from leaching losses, are also considered. This information is then used for model simulations in Sec. 4.3. 

A) No consideration is given to plant phosphorus requirements (i.e., the growth rate of tropical forests is affected only by the atmospheric CO2 concentration). 

C) Plant phosphorus uptake is dependent on [Pjoi]. Sorption and desorption of P in response to changes in [Psq]] are considered (Eq. (6). 

Lambkin DC and Alloway BJ (2003) Arsenate-induced phosphate rdeasefrom soils and its effect on plant phosphorus. Water Air Soil Pollution 144 41-56. 

Recent developments in plant phosphorus nutrition have shown that roots spe-... 

Duff, S.M.C., Sarath, C. and Plaxton, W.C. (1 994)The role of acid phosphatases in plant phosphorus metabolism. Physiologia Plantarum 90, 791-800. 

Jakobsen, I., Leggett, M.E. and Richardson, A.E. (2005) Rhizosphere microorganisms and plant phosphorus uptake. In Sims, J.T. and Sharpley, A.N. (eds) Phosphorus, Agriculture and the Environment. American Society of Agronomy/Soil Science Society of America, Madison, Wisconsin (in press). 

Daroub, S.H., Cerakis, A., Ritchie, J.T., Friesen, D.K. and Ryan, J. (2003) Development of a soil-plant phosphorus simulation model for calcareous and weathered tropical soils. Agricultural Systems 76, 1 157-1 181. 

Jones, C.A., Cole, C.V., Sharpley, A.N. and Williams, J.R. (1 984) A simplified soil and plant phosphorus model. 1. Documentation. Soil Science Society of America Journal 48, 800-805. 

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