Rooting stem cuttings of Chinese chestnut

Rooting of Chinese chestnut (Castanea mollissima Blume.) stem cuttings following treatment with indole-3-butyric acid (IBA) was investigated. Tip and basal cutting from vigorous epicormic shoots and terminal shoots with 2–3 cm of the previous year's wood were taken from mature regions of trees approximately 40 years of age. Cuttings were dipped for 5 s in an aqueous solution of either 3 or 6 g l^?1 IBA. Rooting occurred only in the basal softwood cuttings. Average rooting of 33.5, 5.0 and 1.6% for ‘AU-Leader’, ‘AU-Homestead’ and ‘AU-Cropper’, respectively, was obtained using the 3 g l^?1 IBA solution, and 35.0, 6.7 and 3.3%, respectively, using the 6 g l^?1 IBA solution.     

Vegetative propagation of spice-plants: Root formation in oregano stem cuttings

Stem cuttings of oregano (Origanum vulgare L.) with pre-formed roots responded to a range of IBA and IAA concentrations with increased root emergence and without damage to the cuttings. No similar promotion of rooting was observed in cuttings lacking pre-formed root primordia. The data are discussed with respect to the differentiation and elongation phases of adventitious root formation. Root emergence from oregano cuttings and the continuity of stem vessels into the growing root are described.     

Rooting of peach hardwood cuttings for the meadow orchard

In order to make peach meadow orchard systems feasible, the possibility of propagating peaches by hardwood cuttings and thus reducing the establishment cost of this extremely high-density planting system was examined.A medium temperature of 25°C was harmful to auxin-treated peach cuttings, but excellent rooting could be obtained at a temperature as low as 12°C. Further trials conducted under outdoor conditions in winter in the coastal plain of Israel, with a soil temperature of 12–14°C, did not show any effect of timing on rooting, providing the cutting was taken mature enough (after mid-November) and not later than about 6 weeks prior to bud break. In 30 days root initiation started. Although variations were found between cultivars, 1500 mg/l of indole butyric acid in a 5-second base-dip was found to act well with most cultivars. Good aeration was shown to be critical for good root formation. Leaving the cutting for 1 month in damp sand prior to planting in orchard soil was satisfactory. An area of a few hectares of commercial meadow orchards has already been established with this method.     

Rooting of chrysanthemum cuttings. Influence of irradiance during stock plant growth and of decapitation and disbudding of cuttings

Stock plants of Chrysanthemum morifolium Ramat. cultivar ‘Improved Mefo’ were grown in a controlled-environment room at different levels of irradiance (9, 23, 53 or 90 W m^?2). After 3 weeks, cuttings were excised and rooted for 3 weeks at an irradiance of 16 W m^?2. Cuttings from stock plants grown at the highest irradiance had the highest number of roots, while cuttings from the lowest irradiance had the lowest number of roots.The importance of the presence of shoot meristems for root formation was investigated through disbudding and decapitation at different times after the excision of the cuttings. Removing the buds on the day of excision had no effect on the number of roots formed, while the removal of the buds on day 2 to day 5 after excision had a promotive effect. Removal later than 7 days after excision had no effect at all.The results are discussed from the point of view that an interaction between nutritional and hormonal factors regulates the process of root formation.     

Rooting response of shoot cuttings from three peach growth habits

Current year shoot cuttings were collected in October and August from three growth habits of peach (Compact, Pillar, and Standard) and treated with one of four concentrations of indole butyric acid (0, 250, 1250, and 2500 mg L⁻¹ IBA). Rooting response was measured after 5 weeks in the greenhouse. Little or no rooting occurred with cuttings from any growth habit that was collected in October or in August when treated with 0 and 2500 mg L⁻¹ IBA. In August, the number of shoots that rooted was greater in cuttings from Pillar (79 and 45%) than Compact (13 and 3%) treated with 250 and 1250 mg L⁻¹ IBA, respectively. Cuttings from Standard trees had intermediate rooting of 56 and 6% at 250 and 1250 mg L⁻¹ IBA, respectively. Pillar trees consistently grew more roots with greater root length per cutting than the other growth habits. It is proposed that differences in rooting response among the growth habits may be associated with differences in endogenous auxin concentration that had been found in previous studies. Within peach and possibly other fruit trees, the capacity of shoot cuttings to develop adventitious roots can vary by cultivar and successful root induction with exogenous plant growth regulators may depend, in part, on endogenous hormone levels.     

银杏硬枝插穗不同处理方法生根成活率试验

试验设5个处理,采用春采和冬储两种采穗方式,用自制高分子.激素水凝胶生根膜和ABT1号生根粉100mg/kg溶液对银杏硬枝插穗进行处理。试验结果表明银杏春采插穗涂自制高分子.激素水凝胶生根膜露地与地膜覆盖扦插育苗生根成活率无显著差异,较冬储插穗浸ABT生根粉100mg/kg溶液露地、地膜覆盖扦插可显著提高插穗生根成活率。     

Rooting of shoot cuttings of ornamental shrubs after immersion in auxin-containing solutions

Shoot cuttings of Berberis, Cotoneaster, Lavandula, Prunus, Pyracantha and Viburnum were immersed in a solution of auxin in water. In general, this treatment gave better rooting than the commonly used method of dipping the basal part of the cutting in a powder mixture containing auxin.     

Rooting potential in plum hardwood cuttings: II. Relationships between shoot variables and rooting in cuttings from different sources

There was a positive correlation between shoot length and the proximal diameter of the prepared cutting in stockplant sources of Prunus insititia ‘Pixy’ that had different rooting potential. The precise relationship depended on source, with shoots from a severely pruned micropropagated source, and those developing from the trunks of various stock- plants, usually being thinner for any given length than normal distal cuttings from pruned and non-pruned conventional source stockplants. To a large extent rooting percentage, root numbers and root length increased between sources as the overall ratio of proximal stem diameter to shoot length decreased. Cuttings from the relatively thick, short shoots of the unpruned source were among the poorest rooting, while those from the relatively thin, long shoots from the trunk, and from the micropropagated source, rooted best. This between-source effect reflected the fact that within the less ready rooting sources there was also a negative correlation between the proximal diameter of the cutting and its rooting ability. This relationship was lost progressively as the rooting potential of sources increased, thus giving no opportunity for a trend to occur in the trunk-derived cuttings from the micropropagated source where virtually all cuttings rooted.     

Contributions of the stem to rooting in Eucalyptus grandis Hill ex Maid,stem cuttings

An additional wound at the base of one-node stem cuttings of Eucalyptus grandis increased rooting. Girdling intact shoots reduced rooting in cuttings harvested from them, while girdling cuttings at setting had little effect, suggesting that the internal phloem was active in basipetal transport in the stem. The vertical distribution of roots in additionally wounded cuttings also suggested a changed pattern of efflux from the internal phloem, as well as an increase in water uptake. In one-leaf cuttings more roots emerged from the leaf trace sector of the stem than from the trace of the absent leaf. In two-leaf cuttings the circumferential distribution of roots was uniform except in cuttings (a) reduced to a half-round cross-section at the base, in which rooting was more profuse at the lower of two sites of root emergence, and (b) from lateral coppice shoots whose stems were red-pigmented above with anthocyanins, in which there was less rooting than expected in the red sector. Stem volume was well related to rooting ability, largely explaining variation due to the original position of the cutting within the shoot and crown.     

Rooting response of plum hardwood cuttings to IBA in relation to treatment duration and cutting moisture content

The rooting response of plum rootstock hardwood cuttings to 50, 500 and 5000 ppm IBA was influenced by the duration of treatment in the auxin solution, 18 min, 30 sec and 5 sec being needed to achieve similar levels of rooting at the respective concentrations.

A delay between collection and IBA treatment of cuttings, resulting in a partial water deficit, caused an increase in IBA uptake which was associated with increased rooting. For Myrobalan B a delay of 22 hours at 60 °F (15.5 °C) and 50% RH, leading to a 10% moisture loss, was optimal.     

Production of high quality Ardisia plants by stem tip cuttings

To produce commercially acceptable Ardisia plants, stem tip cuttings from mature plants were rooted and forced in greenhouses. Ten centimeter long cuttings were either treated with 200 ppm 1-naphthalene acetic acid (NAA) for 2 h, 2000 ppm indole-3-yl-butyric acid (IBA) for 10 s, or 0.5 and 1.0% IBA powder prior to sticking them in the rooting medium. Rooting percentage at 45 days exceeded 76% with 2000 ppm IBA treatment which was a significant increase over non-treated control. Rooted cuttings developed into three types of plants: those forming only vegetative shoots without flowers, those forming reproductive shoots with flowers, and those forming both vegetative and reproductive shoots. The ideal plant produced only vegetative shoots when rooted cuttings were transplanted into pots. About 50% rooted cuttings were forced to finish, producing 31 or 40% of high quality plants when rooted cuttings with vegetative shoots were grown in a greenhouse (GH) at temperatures higher than 21/19 °C (day/night) in 1995 or 21/18 °C GH in 1997, respectively. This method shortened the total production time to less than 2 years as compared to 4 years when starting from seeds.     

Rooting of Berberis and Ligustrum cuttings from stock plants grown at selected light intensities

Plants of Berberis thunbergii DC., B. thunbergii DC, ‘Atropurpurea’, Ligustrum obtusifolium Seibold and Zucc. var. regelianum (Koehne) Rehd., and L. × vicaryi Beckett were grown at 37, 53, 70 and 100% full sunlight to determine rootability of cuttings. Rooting hormone levels of 0, 0.1, 0.3 and 0.8% IBA in talc were applied to the cuttings, and % rooting, root length, and fresh and dry weights were recorded. Optimum rooting of cuttings of Berberis resulted when stock plants were grown at 70% light, with 37% light being the next most successful. Optimum rooting of cuttings of Ligustrum obtusifolium var. regelianum resulted when stock plants were grown at 37% light. Rooting of Ligustrum × vicaryi did not respond to light intensity. An interaction between rooting-hormone and light intensity was noted for root length of Ligustrum species.     

The concept of a limiting rooting morphogen in woody stem cuttings

SUMMARY

A rooting morphogen, arbitrarily defined, can be assumed to induce adventitious roots in woody stem cuttings. Auxins generally promote rooting in herbaceous cuttings and are often considered to limit rooting, but they often have little or noeffect when applied to difficult-to-root woody cuttings. They can move in a polar (basipetal) pathway but the polarity of root emergence equally reflects the activity of the vascular system in general, including the phloem, whose contents have a complex composition. The interactions between a morphogen of vascular origin and potential sites for root initiation arelikely to be dynamic and variables such as flux rate or flux direction could be more relevant than static variables such as composition or concentration. The potential sites are not equally sensitive to the rooting morphogen since each cell hasa unique lineage, ontogeny and position, and a prevailing insensitivity could restrict rooting. The contents of the vascular system are inaccessible to potential sites in the stem, so factors affecting efflux and the subsequent attenuation of the efflux, which depend on activity in the whole cutting, could be critical to rooting ability. No simply defined morphogen can be said to limit rooting, and the chemical identity of the morphogen (if definable) is probably unimportant.     

The response of poinsettia cultivars to auxins in root promotion of stem cuttings

Terminal stem cuttings of 9 poinsettia cultivars were pretreated with auxin compounds either singly or in combination prior to rooting in both the winter and summer. The 9 cultivars responded similarly to the auxin containing chemicals with the dual treatment of a liquid dip into either Jiffy Grow at 1 000 ppm or Chloromone at 750 ppm followed by a powder dip with Hormodin No. 2, most effective in stimulating rooting in all cultivars studied except ‘Marble Annette Hegg’. In the winter, the combination treatment of Jiffy Grow at 1 000 ppm and Hormodin No. 2 significantly increased rooting over the separate application of these chemicals, whereas in the summer there was an increased benefit of dual treatment only with ‘C-1 Red’ and ‘Annette Hegg Supreme’. Those cultivars such as ‘C-1 Red’ and ‘Ecke White’ which produced a low number of roots and fresh weight without root promoters, responded most to auxin root promoters.     

Development of an in-vitro rooting bioassay using juvenile-phase stem cuttings of Persea americana Mill.

Summary

A rooting test was developed with shoot cuttings taken from aseptically germinated avocado seed. The rooting required treatments in two steps: (1) three days in a medium containing indole-3-butyric acid (IBA) (25 mg l^?1) and (2) four to eight weeks in an auxin-free medium. Rooting was accomplished with both media containing 0.3× strength Murashige and Skoog salts, 3% sucrose, 0.4 mg l^?1 thiamine hydrochloride, 100 mg l^?1 i-inositol, and 0.8% ‘TC’ agar. The auxin-free medium also contained 1 gl^?1 activated charcoal.     

Progress in the establishment of human embryonic stem cell lines

Embryonic stem(ES) cells are derived from totipotent cells of the early mammalian embryo and are capable of unlimited, undifferentiated proliferation an vitro .The establishment of mouse ES cell lines demonstrated the unmatchable convenience for the study of mouse embryonic development and the particular gene regulation and function. It has been long expected to construct such cell line for human. Here we summarized the development in the construction of human ES cell line, its potential utilization in various fields and the possible ethical dilemmas it brought with were also discussed.     

Rhizogenesis of GF677, Early Crest,May Crest and Arm King stem cuttings during the year in relation to carbohydrate and natural hormone content

The rhizogenesis of GF677, Early Crest, May Crest and Arm King stem cuttings during the year was investigated. The results showed significant differences in the rooting percentage between different dates of cutting collection and also between the four cultivars. Among these, GF677 generally had the highest rooting percentage. Rooting of cuttings was high in October, November and February and relatively low in the periods March–September and December–January. Interactions among cultivars were also found.     

Effect of xylem blockage on stem resistance and water potential in Triplochiton scleroxylon K. Schum. cuttings

Summary

Cuttings of the tropical hardwood species Triplochiton scleroxylon K. Schum. may be extremely difficult to root, depending on the physiological status of the parent plant and propagation conditions. This study examined the importance of xylem blockage in limiting the water supply to unrooted stem cuttings. Stem resistance was greatest in Node 1 cuttings (youngest node) of stock plants, and decreased basipetally. Resistance increased to a maximum, and water potential reached a minimum, 6 d after transfer to rooting medium.The primary site of blockage occurred within 1 mm of the stem base, suggesting an excision-induced wounding response. Histological studies revealed that gums of carbohydrate origin were deposited in some protoxylem elements near the stem base. The influence of these factors in determining cutting survival is discussed.     

Propagation of Wollemi pine from tip cuttings and lower segment cuttings does not require rooting hormones

Domestication of the recently discovered and highly endangered Wollemi pine has relied almost entirely upon serial propagation of cuttings from a very small conservation collection. This study assessed the requirement for applied auxin to induce rooting in tip cuttings and lower segment cuttings of Wollemi pine. Both types of cuttings proved easy-to-root, with mean rooting of 71% for tip cuttings and 82% for lower segments. Auxin application (at 1.5, 3.0 or 8.0 g indole-3-butyric acid/L) did not accelerate root protrusion from propagation tubes or affect final rooting percentages.     

生根粉及不同基质对牡丹传统品种扦插的影响

以菏泽地区定植的29个传统牡丹品种为试材,研究了不同基质、不同浓度的ABT1号生根粉对牡丹扦插生根的影响。结果表明:牡丹属于皮部生根类型,难生根植物;不同基质、不同浓度的ABT1号生根粉对不同牡丹传统品种扦插后的生根率、根数、根长均有不同程度的影响;扦插基质采用珍珠岩纯基质扦插效果较好,ABT1号生根粉500mg/L浸泡插穗30min生根质量较好;不同牡丹传统品种间也存在很大的差异,其中‘玉板白’、‘白玉’、‘蓝田玉’、‘璎珞宝珠’、‘状元红’、‘种生红’、‘十八号’、‘青山贯雪’‘洛阳红’、‘银粉金鳞’等牡丹传统品种较易生根,而‘一品朱衣’、‘姚黄’、‘赵粉’、‘小胡红’、‘盛丹炉’5个牡丹传统品种较难生根。