Effects of short-term low nitrogen supply on cucumber growth,yield and quality during its fruit stage

This study was carried out to evaluate the effects of short-term(7 days)low nitrogen supply(3 mmol/L,6 mmol/L)on growth,yield and quality of cucumber grown in nutrient solution during fruit stage.The mail results were:Moderately low nitrgen supply(6 mmol/L)had no significant effect on net photosynthetic rate of cucumber plant;Plant height of T1 and T2 were 14.9% and 4.2% lower than control,respectively.Yet 7 days after nomal level of nitrogen supply(as control,12 mmol/L),plant height after moderately low nitrogen supply treatment recovered back to the level of control;No obvious differences on leaf eare had been observed during the treatments.However,7 days of nomal level of nitrogen supply led the plant treated by moderately low nitrogen had 12.6% higher of leaf area than control and its yield had no significant differences comparing to control;Fruit quality was improved after treatments.The content of Vc in the fruit which treated by moderately low nitrogen was 13.6% higher than that of control while the content of nitrate reduced significantly by 21.9%.The results indicated that short term moderately low nitrogen supply(6 mmol/L)could improve fruit quality while its growth and yield were not affected.