| الوصف: |
Boron (B), which is an important micronutrient element, takes part in biochemical, physiological, and morphological progress of plants. Boron is available in the form of boric acid or borate and percolation is in the form of uncharged molecules instead of ions. To date, there are still debates on boron transportation in plant species. The assumptions are passive diffusion through plasma membrane, passive diffusion via channel proteins, and high-affinity active transport reconciled by borate transporters under low boron availability. Its deficiency and abundance in soil cause problems in plants. Low boron availability gives rise to inhibited leaf expansion, root elongation, and flower development. On the contrary, excess of boron reduces photosynthetic capacity, pollen germination, and pollen tube growth. Optimum boron supply promotes powerful root development, increases plant pigment content, reduces empty grains, and improves fruit setting and seed production. Boron requirement of plants shows diversities and may vary according to species or cultivar. Therefore, germplasm should be considered especially for the agricultural lands deficient in boron and abounded in boron. For many plant species there is a slight difference between boron requirement and boron toxicity. However, identification of germplasm for the boron deficiency and boron toxicity tolerance is crucial for agricultural planning. Furthermore, boron is in crucial position in the uptake and translocation of other micro- and macronutrients (P, N, K, Zn, Fe, and Cu) in plants. This study highlights the recent advances about the impact of B on plant growth and development under field conditions. Similarly, studies on in vitro screening of B on plant growth and physiological aspects are also summarized. |
