Organic Fertilization of Fruit Trees as an Alternative to Mineral Fertilizers: Effect on Plant Growth, Yield and Fruit Quality

Soil is an essential non-renewable resource for plant growth and yield; it undergoes rapid degradation rates in intensive agricultural areas but it has extremely slow formation and regeneration processes. Consequently, soils from agroecosystems are severely depleted of their nutrients and organic matter pools. The excessive use of mineral fertilizers to supply tree with macro- (N, P, K, Ca, Mg, S) and micronutrients (Cu, Fe, Mn, Zn, B) may raise a concern since they may contain potentially toxic elements, are often expensive and can have a negative impact on the environment. Furthermore, the production of urban and industrial organic wastes is increasing worldwide and environmental friendly strategies for their disposal, for example, compost production, have been developed. Consequently, the necessity to reconcile economic and ecological issues has led to the increase of the use of recycled waste organic fertilizers that can synchronize plant need with nutrient release and, at the same time, improve soil fertility.The enhancement of soil organic matter provides storage of nutrients and water, stimulates soil biological activity and improves C sequestration. Several authors reported beneficial effects of organic matter on orchard soil quality and tree performance.In the present chapter, we will discuss the use of organic matter as an alternative to mineral fertilizers evaluating the effect on plant growth, nutritional status and yield performances.