Abstract:There is certain threshold value of boron for a plant, below which a deficiency symptom will develop, and above which toxicity symptoms appear. A special attention is paid to boron among the essential mineral nutrients because the range between deficiency and excess is narrow. The proper boron input is closely related to the long-term stability of agro-ecosystems. From this perspective, the study on the input, output, cycling and balance of boron plays an important role in determining and optimizing the pro...