Zinc nutrition of onions as influenced by phosphorus

Abstract

In a field study it was found that application of high P induced Zn deficiency symptoms on onion (Allium cepa L.) plants, increased P concentration but decreased that of Zn. Conversely, application of Zn tended to increase Zn concentration of both tops and bulbs and lowered P concentration. Effectiveness of Zn varied with the amount of P applied. Evidently P and Zn are mutually antagonistic. Using sub-soil on the top of raised beds and heavy P fertilization appear to be responsible for inducing Zn deficiency in onions in northern Nigeria.