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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
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Effects of genotype, collection date, auxin treatment, crown position and artificial chilling on rooting and subsequent vegetative growth of Cupressus sempervirens L. softwood cuttings taken from 13-year-old plants were evaluated. Three different clones (318, 296 and 22) previously selected for resistance to cypress cortical cancer caused by Seiridium cardinale were used. In all these clones, both the IBA treated and the untreated cuttings showed seasonal periodicity of rooting. Untreated cuttings rooted best when collected in April (up to 49% for the best clone, i.e. 296) and rooted very poorly in July and October. Auxin treatments appeared unable to overcome this periodicity, as the cuttings taken in July and October did not respond to IBA stimulation. However, in January and April, IBA treatments enhanced adventitious root formation of poorly rooting clones (318 and 22), as well as of clone 296, which performed best (89%) when cuttings were treated in April with 1.5% IBA. Cuttings of each clone collected in the lower third of the crown of the donor trees showed a significantly higher rooting percentage, when compared with those from the upper third. A 4-week post-severance chilling treatment (4°C) significantly enhanced the rooting capacity of cuttings taken in January, while a longer chilling treatment (8 weeks) had a negative effect. The subsequent growth of the rooted cuttings was not affected by either the crown position of the severed cuttings, or the genotype. 相似文献
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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
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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
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Crop productivity under differently lopped canopies of multipurpose trees in Central Himalaya, India 总被引:3,自引:1,他引:3
Ficus species are multipurpose trees well known by rural populations in Sahelian and Sudanian zones of Africa. Their uses are well documented but their amenability for vegetative propagation has not been extensively studied. This paper compares the rooting ability of stem and aerial root cuttings from thirteen Ficus species found in West Africa. It highlights the differences between species belonging to the sub-genera Sycomorus and Urostigma. The former show no capacity to propagate from cuttings whereas the latter, with epiphytic development, can be propagated by cuttings, although this capacity varies among species. Thus, F. thonningii, F. leprieurii and F. ovata are easily propagated, while F. platyphylla and F. elasticoides are propagated with difficulty. The rooting capacity also varies depending on the cutting material used. It decreases in the following order: long leafless hardwood cuttings (pole) > nodal cuttings > apical cuttings. Rooting potential increases when the cuttings are harvested towards the end of the dry season(March to May). Aerial root can be used for cuttings in all species of the sub-genus Urostigma. The capacity of root cuttings to regenerate is greatest when cuttings are collected at the beginning of the dry season (November). In this case, wound-induced adventitious roots arise at the basal end of the cutting while de novo buds are developed from the cambium at the distal end. The subsequent morphological development is identical to that of a stem cutting. These results clarify and allow the optimal use of the knowledge and methods developed by the indigenous people of the Sahel and could assist and promote fig tree (Ficus sp.) domestication in the dry tropics.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献