Evaluation of Wheat Cultivars for Phosphorus Efficiency on Acid Soils and in Nutrient Solution
1994
Camargo, C.E.O. | Felicio, J.C. | de Freitas, J.G. (Campinas Agronomic Institute, Sao Paulo (Brazil))
Phosphorus deficiency is one of the major limiting factors for wheat production under acid soil conditions. P deficiency can be overcome by: (a) the application of phosphorus fertilizer, and (b) the exploitation of genetic variability in the crop. Genetic manipulation of segregating populations to obtain cultivars adapted to medium or low soil phosphorus content, and with better P uptake efficiency and use is possible. The field screening of wheat cultivars under different levels of phosphorus fertilization permits the selection of genotypes which are more efficient at low levels of phosphorus, and also facilitates the evaluation of their response to higher levels of applied phosphorus. The efficiency of phosphorus utilization can be determined by weighing the aerial portion of 30 plants grown for 15 days in nutrient solution containing different concentrations of phosphorus. The Phosphorus Efficiency Ratio (PER) is calculated by dividing the shoot weight (Mg) by the content of phoshorus of the shoot (mg). The relationship between field experimentation and the nutrient solution technique to identify genotypes with higher phosphorus uptake efficiency is discussed.
显示更多 [+] 显示较少 [-]