杂种鹅掌楸扦插苗营养元素含量的分布

本文利用不同浓度的外源激素处理杂种鹅掌楸的扦插繁殖幼苗,并通过烘干法、凯氏法、原子吸收等方法,对扦插繁殖幼苗的根、茎、叶3个器官生物量及其营养元素进行测定。结果表明:不同浓度的外源激素(处理1:IBA50gkg-1+NAA300gkg-1;处理2:IBA50gkg-1+NAA300gkg-1)处理插穗后,根、茎、叶的生物量均有一定程度的提高。在所有的扦插苗中,其根、茎、叶内的含C量差异不大,但茎内的N、P、K、Ca含量较根、叶的少。方差分析结果表明:不同浓度外源激素处理的同一器官后,其C/N及P、K、Ca的含量没有明显的差异;而同一浓度外源激素处理不同器官之间的4种营养元素的含量有显著或极显著的差异。并且扦插生根苗体内营养元素含量较低,在大田栽培时,应及时施肥补充营养,以提高幼苗生长适应能力。图1表4参12。

Nutrient element contents of cutting seedlings of hybrid species (Liriodendron chinense x tulipifera)

The cutting seedlings of Liriodendron chinense x tulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 gkg-1 + NAA of 300 gkg-1; treatment2: IBA of 100 gkg-1 + NAA of 300 gkg-1). The biomass and the nutrient element contents for different organs (root, stem, leaf) of cutting seedling of Liriodendron chinense x tulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P, K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents, while there existed significant or very significant difference in contents of the four nutrient elements in different organs with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result, additional fertilizer should be applied to the seedlings when they were planted in the field.