phosphorus uptake efficiency in corn, sugar beet and groundnut

abstract plant species differ in their ability to grow at low available p soils in other words, plant species differ in p use efficiency at low p supply. this ability can be investigated by comparing p uptake efficiency of plants and relative effective factors. a pot experiment was carried out in the growth chamber and sugar beet, maize and groundnut were grown in a low available p soil in a completely randomized design with three p fertilizer levels of low, medium and high. three harvests were performed at two different growth periods. the results showed that at low p supply, sugar beet was the most efficient plant among three species as it showed the highest relative yield. the higher p use efficiency of sugar beet was due to a higher p uptake efficiency. phosphorus uptake for sugar beet was 29 mg p plant-1 while those for maize and groundnut were 19 and 0.8 mg p plant-1, respectively. the main reason for higher p uptake efficiency of sugar beet was its higher p influx as compared to maize and groundnut. under low p supply during the first growing period, p influx of sugar beet was higher than that of maize and groundnut by factor 4 and 22, respectively. finally, the higher p use efficiency of sugar beet was due to a higher p uptake efficiency which in turn was due to a high p influx.