Plant Nutrition for Sustainable Food Production and Environment

Abstract

The crop species canola, narrow-leaf lupin, pigeon pea, soybean, sunflower, wheat and white lupin were grown in an Oxisol low in plant-available phosphorus (P), but high in total P, to investigate their capacities to access poorly-available soil P. The soil was labelled with 32p, and the plants were grown in a phytotron glasshouse. Values for specific 32p activity in plant tops were: white lupin < pigeon pea and narrow-leaf lupin < soybean and wheat < sunflower < canola. Values for isotopically exchangeable P (L-values) were white lupin» pigeon pea> canola, sunflower and wheat> narrow-leaf lupin and soybean. The results show that white lupin and, to a lesser extent, pigeon pea obtain P from a soil pool not available to the other species, particularly canola.