Factors Influencing Absorption of Phosphorus and Zinc by Grain Crops and the Responses of Pea and Wheat to Phosphorus and Zinc Fertilisation

Abstract

The initial experiment was designed to compare the responses to P and Zn fertilisers of 'Pisum sativum' L. var. Dundale and 'Triticum aestivum' var. Sunco grown on a grey clay of low P status. P was applied at four rates (0, 10, 20 and 40 kg P/ha) and Zn at two rates (0 and 5 kg Zn/ha). For peas, there was a significant response in shoot dry weight and P concentration when P was applied at 20 and 40 kg/ha whereas wheat responded at 10 kg/ha and above. Zn fertiliser increased the node number in peas and Zn concentration in both peas and Wheat. Any phosphorus-zinc interaction effects were small and variable compared to the main P and Zn effects. Following this experiment a sequence of experiments was conducted to compare the responses of pea to P fertiliser application under field and glasshouse conditions. Since the response of wheat to P application in Australia is well recognised, unlike that of peas for which little data is available, it was decided that further experiments be pursued only with peas.