芥兰营养生理的研究：Ⅰ.养分吸收特性

芥兰对氮磷钾的吸收以钾最多,氮其次,两者差异不大,磷最少。钙的吸收比氮、钾少而比磷、镁多。镁的吸收比磷少。氮磷钾的吸收比例因生长期而不同。花芽分化前氮钾比例较高,且钾明显大于氮,菜薹形成期间氮钾比例缩小,采收时氮磷钾比例为5.3:1:5.5,植株的氮磷钾含量随着生育过程逐渐降低。吸收量则随着生育过程而逐渐增加,菜薹形成期间的吸收量占总吸收量的3/4以上。氮磷钾等养分的分布随生育过程而变化。花芽分化前95％以上的养分分布在茎叶,花芽分化后的菜薹形成期间分布在茎叶的养分比例逐渐减少,而菜薹占的养分比例则迅速增加,采收时占氮3/4,占磷、钾、钙和镁的2/3左右。

STUDIES ON THE NUTRIENT PHYSIOLOGY OF THE CHINESE KALE (Brassica alboglabra Bailey) I. CHARACTERISTICS OF NUTRIENT ABSORPTION

In the amounts of NPK absorbed by the Chinese kale plant, K was greatest, N next and P Leart. The absorption ratio of NPK changed with the growth stage, NK level in the plant was higher, and K uptake was obviously greater than N before flower bud differentiation, thereafter, NK became proportionally less during flower stslk formation, the ratio of N, P2O5, K2O being 5. 3 : 1 : 5. 5 al harvesting.The contents ( % ) of N, P and K in the Plant decreased gradually, bnt the amounts absorbed increased gradually with growth. The uptake during flower stalk formation constituted 3/4 of the total amount.The distribution of N3 P and K changed with growth, and more than 95% of them were distributed to stems and leaves before flower bud differentiation. The proportion of nutrients in stems and leaves decresed rapidly during flower stalk formation. At harvesting, the proportion of N, P, K, Ca and Mg in the flower stalk reached 3/4 of total N, 2/3 of total P, K, Ca and Mg, respectively.