The Role of Boron in Plant Growth

Abstract

The relation of boron to vegetative growth and seed production of Trifolium pratense L. and Vicia faba L. has been studied using sand and water culture techniques. It was found that the addition of a very small quantity of boron was sufficient to restore deficient plants to normal growth and it would appear that boron fertilizers will only be beneficial where deficiency symptoms have been shown. The rapid cessation of cell division under conditions of boron deficiency was demonstrated and was responsible for a decrease in both vegetative and seed yields through reduced branching and flower differentiation. No special association of boron with the functioning of pollen or with chromosome behaviour was found. The cessation of cell division is responsible for the abnormalities associated with boron deficiency but the cellular reactions involved remain unknown. Previous suggestions of the role of boron in plant metabolism are discussed in the light of the conclusion that boron is essential for the maintenance of meristems.