长蕊杜鹃扦插内源激素变化及解剖结构观察

以野生长蕊杜鹃半木质化茎段为试材,采用植物生长激素KIBA,KNAA和Hormodin对插穗进行处理,测定不同生根期内源激素IAA、GA3、ZR、ABA含量,对扦插不同时期插穗茎段进行电镜扫描。结果表明:先快蘸液态KNAA(3 000mg·L-1),再迅速蘸取粉状Hormodin#1处理对插条生根具有显著影响,插穗生根率达到了81.25%;较高浓度的内源IAA含量有利于根原基分化形成,GA3含量上升与插穗愈伤组织的诱导、不定根的形成呈正相关性,低水平的ABA更有利于长蕊杜鹃扦插生根;插穗在根原基分化和愈伤组织形成时期消耗內源ZR,在不定根长出后自身合成ZR;通过对淀粉粒研究表明扦插期补充糖类物质是必要的,簇状晶体产生表明钙调控等生理机制形成。

Changes of Endogenous Hormones and Anatomical Structure of Rhododendron stamineum During Cutting Propagation

The semi-hardwood stems of wild Rhododendron stamineum were collected and treated with KIBA, KNAA and Hormodin. The contents of endogenous hormones IAA, GA₃, ZR, and ABA were measured and the stems were scanned with SEM during the rooting period. The results indicated that double dips (quick dipped into liquid KNAA (3 000 mg·L^-1) and then the powder Hormodin #1 (1 000 mg·L^-1)) had a significant effect on rooting and resulted in the highest rooting rate of 81.25%. During the rooting process, higher concentration of endogenous IAA contents was conductive to the formation of root primordium differentiation, GA₃ content showed a positive correlation with the cuttings callus induction and adventitious root formation, and low levels of ABA should promote rooting of cuttings. Cuttings needed endogenous ZR during root primordium differentiation and callus formation and it could synthesize own ZR after root initiated. It is necessary to supplement carbohydrate during rotting period through the research of starch grains, the emergence of cluster-like crystals indicated that the mechanism of Ca regulation has been established.