Abstract: This test was carried out with three-years-old precocious walnut seedlings(Juglans regia)cultivated in soil pots.The water contents of pot soil were weighed to 100%,75%, 50%, 30% of Field Capacity (FC) respectively from two to six weeks after the pistillate flower bloom (the sib of May).After this period, the seedlings were watered nomally till fruit ripeness. The results showed that:leaf,shoot and nut growth were all best in 75% FC treatment.Water stress(50%FC,30%FC)and waterlogging(100%FC)reduced the leaf water potential and net photosythesis rate and obviously inhibited the growth of leaf,shoot and nut.This inhibition was not made up by watering or draining after this period.The leaf structure was mainly influenced by water stress.Drought resistance of walnuts was also discussed in this paper.

Key words: Precocious walnuts, Water stress, Growth and fruitage