Nitrogen Nutrition of Fruit Trees to Reconcile Productivity and Environmental Concerns.

Although perennial fruit crops represent 1% of global agricultural land, they are of a great economic importance in world trade and in the economy of many regions. The perennial woody nature of fruit trees, their physiological stages of growth, the root distribution pattern, and the presence of herbaceous vegetation in alleys make orchard systems efficient in the use and recycling of nitrogen (N). The present paper intends to review the existing literature on N nutrition of young and mature deciduous and evergreen fruit trees with special emphasis to temperate and Mediterranean climates.

Tree size and flowering intensity as affected by nitrogen fertilization in non-bearing orange trees grown under Mediterranean conditions.

'Lane Late' orange trees. Five nitrogen (N) rates were used in a randomised block design with three replicates. The 180 g N tree(-1) over three years led to the greatest canopy width (176 cm) and volume (2,697 dm3).