The experiments were carried out with yangmai 158 on the experiment farm and steel shed of Anhui Agricultural University for two years from 2001 to 2004. The pot experiment was originally designed with four different water application treatments. The CK(check) treatment was 75~80% of maximum field capacity. The light water stress treatment (T1) was 65~70% of maximum field capacity. The medium water stress treatment (T2) was 55~60% of maximum field capacity. The heavy water stress treatment (T3) was 45~50% o...