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81.
光皮桦组织培养技术研究 总被引:3,自引:1,他引:3
对光皮桦带芽茎段组织培养技术的外植体启动培养、丛生芽增殖以及试管苗生根和炼苗移栽等方面开展研究,结果表明,外植体灭菌最优流程:经75%酒精1~1.5 min处理后转入0.1%HgCl2溶液消毒处理7 min;在改良MS+6-BA5.0mg.L-1+NAA 0.01 mg.L-1的培养基上,外植体启动速度最快;在改良MS+6-BA 4.5 mg.L-1+蔗糖40 g.L-1+NAA0.01 mg.L-1的培养基上,外植体增殖系数最高可达6.9倍;在改良WH+IBA 3.0 mg.L-1+NAA 1.5 mg.L-1培养基中,继代苗的生根率最高;试管苗移栽的最佳基质为沙∶田园土=1∶1。 相似文献
82.
The literature on rootstock effects (on scions) in conifers was reviewed, specifically: graft success, compatibility, size, reproduction, phenology, crown and needle characters, mineral contents, organic compounds, water relations, disease resistance and wood properties. Scions usually had higher graft success and less incompatibility on more closely related rootstocks although there were exceptions. Even intergeneric grafts have succeeded on occasion. Although there were marked rootstock effects on growth and reproduction, the effects did not follow a pattern with increasing relationship. It is also likely that some crown characters and the nutrient content of scions can be manipulated by the use of rootstocks. For many characters, a specific rootstock may give a desired result only for a limited number of scion types (species, cultivars or clones). With some exceptions, the review shows that the subject has not been comprehensively studied. Many of the studies were either short-term, inadequately replicated, or poorly designed to allow firm conclusions about rootstock effects. The physiological and biochemical mechanisms, which cause the changes seen in morphology, are not well understood. Further research and more comprehensive study of rootstock effects on scion biology are recommended. 相似文献
83.
福建山樱花扦插繁殖及其影响因子研究 总被引:13,自引:2,他引:13
在塑料拱棚下进行福建山樱花半木质化枝条扦插繁殖试验,分别进行了不同扦插繁殖时间、不同浓度的ABT1号和IBA处理、不同扦插基质和添加钙镁磷对生根促进剂提高福建山樱花扦插生根的影响试验及综合试验。结果表明,福建山樱花半木质化枝条扦插繁殖以冬末春初为适宜时期,以2份素沙+1份粘性黄土为扦插基质,插穗经IBA 2 500 mg.L-1+钙镁磷沾根I、BA 3 750 mg.L-1+钙镁磷沾根或IBA 5 000 mg.L-1浸泡处理均有良好的促进生根效果,平均插穗生根率和平均一级不定根数最高分别可达86.67%和4.68条。 相似文献
84.
研究不同植物生长调节剂及质量浓度对带芽茎段分化、继代和生根的影响.结果表明:月季芽的分化培养基为M S+BA 1.0 m g.L-1+NAA 0.1 m g.L-1,不定芽的诱导率为80%;在M S+BA 1.0 m g.L-1培养基上继代增值的效果较好;NAA的生根效果优于IBA,以1/2M S+0.5 m g.L-1NAA最佳. 相似文献
85.
以虎眼万年青的叶片为外植体,对不同激素浓度的愈伤组织和不定芽的诱导情况以及再生芽的无糖培养情况进行了研究.结果表明:适于愈伤组织诱导及不定芽分化的培养基为MS+BA1.0mg/L+NAA0.1mg/L,适宜的继代培养基为MS+BA0.5mg/L+NAA0.1mg/L;用无糖培养体系进行生根培养时,基质中NAA浓度为0.1mg/L时,再生芽的生根率达94%,种苗质量优于常规组培. 相似文献
86.
87.
毛白杨,河北杨多代循环繁殖方法的研究 总被引:3,自引:1,他引:3
从1983年起,对毛白杨、河北杨的扦插繁殖育苗及其机理进行了研究,研究出“多代循环繁殖新方法”,无需任何处理,也无需地膜覆盖,使大田育苗成活率稳定在80%左右;同时研究出快速、简便、繁殖系数高的优树根萌条培育新技术,为毛白杨、河北杨优树的无性系测定、无性系育种和无性系造林创造了条件。 相似文献
88.
Rooting of baldcypress cuttings 总被引:6,自引:0,他引:6
A test of the rooting performance and growth of cuttings from 1-year-old and 25-to 50-year old baldcypress (Taxodium distichum L.) branch tips is reported. Rooting of cuttings from one-year-old trees averaged 75% (0.1% IBA treatment) and 88% (control), cuttings from 25 to 50-year-old trees averaged 12% in both the IBA treatment and the control treatment. Indole-3-butyric acid at a 0.1% concentration did not enhance rooting, but resulted in a significant increase in shoot dry weight on cuttings from one-year-old trees. The results of this experiment suggest that cuttings from mature baldcypres trees have the potential to root, thereby, additional rooting techniques such as girdling and stump sprouts is worthy of pursuing. 相似文献
89.
Immature female gametophytes and enclosed zygotic embryos of slash pine (Pinus elliottii Engelm.) collected at various developmental stages were cultured either on eight initiation media supplemented with different plant growth regulator (PGR) combinations or on LPM medium solidified with two brands of agar. Embryonal-suspensor cell masses extruded from gametophyte explants infrequently produced white or translucent mucilaginous embryogenic cultures. Variation in extrusion frequency was observed across seed sources (families), explant collection dates, agar types and culture media. Increased explant maturity (as related to collection dates) reduced cell extrusion rates. Four types of extrusions were grouped according to their morphology. One type of extrusion produced the greatest number of established and long-surviving embryogenic cultures. This extrusion type (type I) was associated with an extrusion condition termed empty in which the entirety of the embryonal-suspensor mass was extruded out of the gametophyte. Three other extrusion types (types II, III and IV) showed less culture establishment and survival. 相似文献
90.