Abstract

Boron (B) deficiency and toxicity are widespread problems in many agricultural crops, including citrus. Boron stresses affect the normal growth and development of citrus plants, and cause impairments of cellular functions and physiological processes in citrus plants. There has been significant progress in our understanding of the physiological responses and the tolerance of citrus plants to B stresses during the past decade. This paper reviews the effects of B stresses on citrus growth, root morphology, plant mineral nutrients, leaf structure, carbohydrates, pigments, photosynthetic enzymes, photosynthesis and antioxidant system, and the tolerance mechanisms (differences in cultivars, rootstocks and scion-rootstock combinations, root morphology, B uptake and distribution) of citrus plants to B stresses. Some aspects that need to be further studied were also discussed.

Key words: Antioxidant system, boron deficiency, boron toxicity, citrus, photosynthesis, tolerance to boron stresses.