芥兰营养生理的研究——Ⅲ.氮钾营养对芥兰菜薹形成过程体内生化物质的影响

STUDIES ON THE NUTRIENT PHYSIOLOGY OF THE CHINESEKALE (Brassica alboglabra Bailey)Ⅲ. EFFECT OF N AND K FERTILIZER ON BIOCHEMICAL SUBSTANCES DURING FLOWER STALK FORMATION OF THE CHINESE KALE

试验设N_1,K_1,N_1K_1,N_1K_2,N_2K_1,和N_2K_2六个处理,研究芥兰菜薹形成过程生化物质的变化。结果表明,芥兰花芽分化前,茎中可溶性糖、还原糖、蛋白质和游离氨基酸不断积累,可溶性糖/蛋白质(SS/TP)比逐渐提高。当碳氮化合物积累至小高峰,SS/TP比达一定值时,花芽便分化。K_1处理的碳化合物含量最高,而氮化合物含量最低,SS/TP比高,花芽分化最迟,其他处理的花芽分化期差异不大。 在菜薹形成过程,叶片的叶绿素含量迅速增加,同时茎中糖和游离氨基酸逐步积累,但蛋白质含量下降,至现蕾前后叶片的叶绿素和茎中糖含量开始下降,茎中蛋白质含量则有所回升。K_1处理的可溶性糖积累最多,而蛋白质减少最明显,SS/TP比明显高于其他处理,其菜薹发育最差。 在花芽分化过程,茎端DNA含量变化不大,RNA含量在花芽分化前逐渐增加,达一小高峰后便花芽分化。菜薹形成期间,茎端DNA含量缓慢增加,而RNA含量迅速增加。各处理的变化趋势无大差异。

In this experiment was studied the effect of N and K fertilizer on biochemical substances during flower stalk formation of the Chinese kale by six fertilizer treatments designated N1, K1, N1K2, N2K1, and N2K2. The results showed that soluble sugar, reducing sugar, protein and free amino acid accumulated in the stem, and the radio of soluble sugar to total protien (SS/TP) increased gradually before flower bud differentiation. When both carbohydrate and nitrogen compounds accumulated to a little peakk and SS/TP tatio achieved a certain value, flower bud was differentiation occurred. The carbohydrate content was highest, the protein content lowest and SS/TP ratio high, but flower bud differentiation was latest in K1 treatment when compared with other treatments.During flower stalk formation, the chlorophyll content of the leaves increased rapidly, free amino acids and sugars in the stem accumulated but the protein content wad reduced. However, a chift occurred in which the chlorophyll and the sugar content decreased, but the protein content increased again at around flower bud production. The soluble sugar content was highest, the protein content in the stem lowest, so that the SS/TP ratio was high, but the flower stalk development was least in K1 treatment in comparison to other treatments.The DNA content in stem apice showed no marked change, but the RNA content increased gradually and reached a little peak before flower bud differentiation. Durinng flower stalk formation, the RNA content increased rapidly whereas the DNA content slowly. These changes did not significantly differ among all treatment.