Soil physicochemical characteristics and leaf nutrient contents on banana farms of North Queensland, Australia

Abstract

Context Banana production in Australia is in three primary sub-regions within tropical North Queensland and the industry faces a variety of challenges including costs of production, disease and pests, and environmental impacts. The range of soil characteristics and banana leaf nutrient status on banana farms has not previously been systematically described. This knowledge gap makes it difficult to adapt research, management recommendations, and regulations to the needs of the three primary growing sub-regions. Aims In this work, we aimed to identify key soil factors that differentiate growing sub-regions, and provide context for future research and industry regulation. Methods We characterised soil and banana leaf samples from 28 banana farms on soil types accounting for >85% of Australia’s banana production. Key results and conclusions Variation in soil properties and leaf nutrient concentrations were driven largely by site- (principal component 1 in both cases) and management-related variables (principal component 2 in both cases). Management-related foliar nutrient concentrations did not differ between regions despite differences in the associated soil variables. The most important site characteristics appeared to be soil parent material and climate. The Mareeba sub-region has basaltic soils, low rainfall and temperature, whereas the other two sub-regions are hotter, wetter and have a variety of soil parent materials. Leaf nitrogen concentrations were mostly below the regulated limit for additional nitrogen fertiliser application. Implications Our findings can facilitate sub-region-specific site selection for research, extension, and monitoring and more targeted regulation of banana production- and environment-related issues.