根区温度对水培生菜生长和矿质元素含量的影响

摘要

The plant growth and mineral elements content were studied in hydroponically-grown lettuce (Lactuca sativa L.)under five different root zone temperatures.The results showed that with the increase of root zone temperature,the lettuce yield per plant increased first and then decreased,reaching the maximum value at 25 ℃,and the dry matter content was the highest.Effects of root zone temperature on lettuce leaf net photosyn-thetic rate and the content of mineral elements were similar to the yield.Under the treatment of 35 ℃ root zone temperature,the lettuce growth and mineral elements accumulation were significantly inhibited,and the nitrate content decreased significantly.The results indicated that the most suitable root zone temperature was 25 ℃ for the growth and mineral elements absorption of hydroponically-grown lettuce.%在水培条件下，研究了5个根区温度对生菜（Lactuca sativa L.）生长和矿质元素含量的影响。结果表明：随着根区温度的升高，生菜单株产量呈先增加后减少的趋势，在25℃时达到最大值，且干物质含量最高；根区温度对生菜叶片净光合速率和矿质元素含量的影响与对产量的影响相似，即在25℃时达到最大值。35℃根区温度处理下，根叶生长和地上部矿质元素的积累受到严重阻碍，生菜叶片硝酸盐含量显著下降。在5个根区温度处理中，25℃对水培生菜的生长及矿质元素的吸收最为适宜。