FRUIT AND VEGETABLE QUALITY AS AFFECTED BY THE USE OF COMPOST AND OTHER ORGANIC AMENDMENTS

Abstract

The horticultural literature shows that there are two pre-harvest factors that can reduce fruit and vegetable quality, i.e., nitrogen and water. An excess of either soil nitrogen or water can increase harvestable yield but it will decrease post-harvest quality. Compost and other organic amendments, e.g., mulch, green mulch, biogas slurry and biofertiliser, and compost tea, affect soil properties that in turn affect soil nitrogen and water availability. The effect of compost and other organic amendments on soil nitrogen will be explained in terms of their effect on the soil nitrogen cycle, especially N mobilisation and immobilisation and the carbon/nitrogen (C/N) ratio which is an important determinant of the available soil nitrogen. The research on the effects of compost and other organic amendments on post-harvest quality will be summarised. In general, the published research shows that compost and other organic amendments can improve post-harvest quality parameters but not always. Recent research is showing that integrating various composting strategies and combining with other crop management factors, e.g., water management, improves post-harvest benefits more than just implementing composting alone.