Abstract: The research has compared the influences of different B fertilizers，sorbitol-boric acid（SB）and boric acid（BA），on citrange rootstock growth and physiology characteristics by means of solution culture. Both fertilizers increased the fresh weight，dry weight and plant height of various parts of the rootstock seedling，and SB played a prominent role in underground growth. The transfer of SB in blades or other parts of the ground was easier than BA. There was no significant difference between the B content of SB and BA in roots and stems，but B content and B accumulation in leaves were significantly higher than BA，and the total B content proportion was significantly higher than BA. Various parts of potassium，calcium and magnesium content in SB were higher than that in the control，while the content of element in different parts of BA was higher than SB. Boron deficiency can lead to carbohydrate accumulation in leaves，and SB was more effective than BA in promoting the transport of polysaccharide substance in leaves. The soluble sugar contents in SB treatment were decreased separately by 26.3% and 11.8% than in the control and BA treatment，and the starch content decreased by 43.5% and 26.1%. SB was better than BA in raising resistance ability. Two B fertilizers were significantly lower than the control in Pro and the damage rate of leaves，SB and BA treatments were decreased separately by 20.6% and 19.6% than the control，and the damage rate was decreased separately by 13.3% and 16.5%，MDA content of SB leaves significantly decreased by 19.4% than BA. SB was better than BA in improving the growth and development of root of trifoliate orange rootstock. Besides，SB can effectively reduce the content of carbohydrates in leaves，and help the transfer of photosynthetic products. However，SB and BA had the same effect on reducing the accumulation of harmful substances，protecting the plasma membrane of leaves.

Key words: citrus, rootstock, boric, element content, polysaccharide, proline