Nutrition management of tropical fruits grown in North Queensland, Australia

Abstract

The wet tropical coast and drier elevated tablelands of tropical north Queensland are major production areas for tropical and sub tropical fruits including durian, longan, lychee, mangosteen and rambutan, offering important economic diversification opportunities for sugar cane and tobacco farmers. An understanding of nutrition management and its effects on production has been a key area of research over the last five years. Yield versus fertiliser inputs were examined and the use of nutrient budgets to manage fertiliser inputs is discussed. The project was unable to identify any direct links between tree nutritional status, fertiliser inputs and yield. This suggests that within the range of nutrient status observed, other factors than fertilisation, such as pruning practices and climate, play a more important role in flowering and subsequent yield and/or that the method for measuring nutrient status does not reflect nutrient supply mechanisms appropriately. Leaf and soil nutrient concentration guidelines have been developed to assist growers to manage fertiliser inputs appropriately. This paper describes the grower survey methods used to quantify the guidelines.