The Mineral Nutrition of Developing Fruits of Kennedia prostrata R. Br. Ex Ait., A Perennial Australian Legume

Abstract

The nutrition of developing fruits of K. prostrata was studied in natural habitat near Perth, Western Australia. Changes in the contents of specific nutrients in pods and seeds are described. Seeds accumulated > 80% of the N and P of the fruit, 36-58% of its K, S, Ca, Mg, Fe and Zn but < 25% of its Na. Pods lost 77-87% of their N and P, 20-39% of their Mg, Zn, Mn and Cu, and 9-15% of their K, S, Ca and Fe during senescence. Na was not withdrawn from pods. Retranslocation from pods were considered to be capable of providing > 50% of the N and P accumulated by seeds, although the values for most nutrients and DM ranged from 16 to 35%. Fruit-tip exudate had some characteristics of phloem sap (e.g. alkaline pH, 15-2096 sucrose, a high level of K^-), but contained 2 . 5 mg/ml Mg²⁺ and appeared to be contaminated with mucilage. The testa contained 75% of the seed's dry matter and the major part of its K, Ca, Mg, Mn and Ca; the embryo most of the seed's N, P and S. Information for Kennedla is discussed in relation to data for cultivated legumes as there is no comparable study on another native legume.