Humic acid-mediated chemical processes in citrus fruit growth: A comprehensive review

Abstract

Humic acids, complex organic compounds derived from the decomposition of plant and animal matter, are widely recognized for their positive effects on plant growth and development. This review explores the role of humic acid-mediated chemical processes in citrus fruit growth, with a particular focus on its effects on soil chemistry, nutrient uptake, and plant metabolism. Citrus cultivation, which is economically significant globally, faces numerous challenges, including nutrient deficiencies, soil degradation, and environmental stressors. Humic acids, as a natural soil amendment, offer a sustainable solution to enhance soil fertility, improve water retention, and promote plant health. Through mechanisms such as enhanced nutrient availability, hormonal regulation, and improved microbial activity, humic acids facilitate improved citrus yield and quality. Various studies have demonstrated that humic acid applications can influence key growth parameters, such as fruit size, sugar content, and resistance to abiotic stress. Furthermore, humic acids have been shown to mitigate the harmful effects of chemical fertilizers by promoting more efficient nutrient utilization, thereby reducing environmental pollution. This review synthesizes the findings of recent studies on the effects of humic acid on citrus fruit growth, providing a comprehensive analysis of its potential as a sustainable agricultural input. The goal is to offer a clear understanding of the chemical processes involved in humic acid-mediated growth enhancement and to outline future research directions for optimizing its use in citrus farming.