Effects of different organic nutrient solution on the growth of lettuce
Using Italian bolting-tolerant lettuce as material,we studied the effects of organic nutrient solution formula with different organic substances(urea,humic acid,potassium fulvic acid,EDTA-2Na)on the growth and quality of lettuce by soil-less cultivation.The results showed that nutrient solution containing low concentration of urea could effectively increase the fresh weight of lettuce root,but nutrient solution containing higher concentration of urea could reduce it.Besides,adding 50 mg·L-1 and 100 mg·L-1 EDTA-2Na to the nutrient solution can obviously increase the soluble sugar content in lettuce.Both humic acid nutrient solution and urea replacing 40%nitrate nitrogen treatment can effectively increase soluble protein content in lettuce.To sum up,the best treatment is urea replacing 40%nitrate nitrogen in the nutrient solution with urea.
NETL
NSTL
万方数据
维普
