Effects of growth regulators on growth and flowering in Hippeastrum hybridum hort

Soaking of bulbs in 3 concentrations of indoleacetic acid (IAA), gibberellic acid (GA₃), 2-chloroethyltrimethyl ammonium chloride (cycocel) or 2-chloroethylphosphonic acid (ethrel) showed various responses on growth and flowering. IAA increased the weight and number of bulblets, GA₃ increased bulb weight. Cycocel (1000 mg l^?1) increased the number of flowers, while GA₃ increased the diameter of the flowers.Application of IAA at 100 mg l^?1 and GA₃ at 10, 100 or 1000 mg l^?1 twice as foliar spray at an interval of 30 days promoted the number of bulblets on the treated plants, while high concentrations of cycocel and ethrel (1000 mg l^?1) increased the weight of bulblets. All concentrations of IAA, GA₃ and 1000 mg l^?1 cycocel increased the number and size of the flowers.     

Poststorage quality and rooting ability of Epipremnum pinnatum cuttings after treatment with ethylene action inhibitors

Summary

The influence of the ethylene action inhibitors STS and 1-MCP on poststorage performance and subsequent rooting of cuttings was investigated in Epipremnum pinnatum. Unfavourable storage conditions resulted in decreasing poststorage quality of single-eye cuttings, expressed as leaf drop and yellowing. 1-MCP and STS prohibited leaf drop and yellowing in E. pinnatum. STS pretreatment decreased rooting ability significantly, measured as percentage of rooted cuttings, number of roots, total root length and dry weight. STS caused severe injuries to the cuttings, which were worse if the cuttings were stored rather than propagated immediately. There was no significant difference in rooting between 1-MCP treated cuttings and untreated control in either stored or unstored cuttings. The influence of ethylene action inhibitors on rooting and a possible use of 1-MCP for practical use to increase poststorage performance in cuttings are discussed.     

Auxin synergists in the rooting of mango cuttings

Preplanting application of phenolic compounds, p-hydroxybenzoic acid p-coumaric acid and ferulic acid, in most cases promoted auxin-induced rooting on cuttings of mango, a difficult-to-root fruit plant. The ethylene-releasing chemical CEPA (ethrel, ethephon) also stimulated rooting in the presence of auxins. Synergism was more pronounced in the presence of IBA than with IAA. To a certain extent, root-promoting effects of auxins and non-auxin chemicals were related to the utilization of carbohydrate fractions from the region of root formation. Utilization of reserve polysaccharides assumed greater importance only during the root-development phase.     

糙叶杜鹃扦插技术及插条营养物质变化研究

以糙叶杜鹃半木质化茎段为材料,采用KIBA、KNAA和Hormodin对插穗进行处理并测定不同生根期内可溶性糖和全氮的含量。结果表明:快蘸液态KIBA(3 000mg/L)处理对插穗生根具有显著影响,处理后的插穗生根率为92.55%,达到极显著水平;较高的C/N比有利于插穗生根,在扦插生根过程中碳水化合物是插穗不定根形成和生长所需的营养物质,在插穗愈伤组织的形成和根原基的发生期需消耗一定的可溶性糖;高浓度的氮素不利于插条的生根。     

Mist propagation of peach and almond × peach hybrids

Several factors contributing to the successful rooting of stem cuttings of four peach clones and one almond × peach hybrid under intermittent mist were tested. With the almond × peach cross, leaf-bud cuttings were also tested.Severe cutting back of adult peach mother trees in winter favoured rooting of the cuttings, but less severe cutting back induced maximum roots per cutting.For short periods vermiculite was found to be a suitable medium. Sand alone or mixed with vermiculite or gravel gave poor results. Gravel alone or mixed with vermiculite was intermediate. For growing the rooted cuttings for a longer period, a mixture of perlite and peat was very suitable.A period of illumination of 3 h starting at midnight with incandescent light improved rooting of peach cuttings in August and October, but not in June.With cuttings obtained from old fruit-bearing peach trees highest rooting rates were obtained in July, but best root development occurred when rooting was carried out in October. In July rooting rate of basal cuttings was much higher than that of terminal ones. Success with leaf-bud cuttings (including a small branch piece) obtained from young mother trees of the almond × peach hybrid was only achieved at the end of May or in June.Dipping the base of peach cuttings in water before rooting was of advantage with one cultivar rooted in September, but of no advantage with another cultivar rooted in June.When the base of stem cuttings was dipped for a prolonged period in IBA solutions of various concentrations, highest rooting rates were obtained with 25–50 ppm IBA for peaches and with 200 ppm for the almond × peach hybrid. The addition of Phygon XL to this solution was of some advantage for peach cuttings. The concentration inducing maximum root development was higher than that required for maximum rooting and callusing. The optimal IBA concentration for rooting of almond × peach leaf-bud cuttings was 100 ppm.Penetration of the IBA into the leaf-bud cuttings reached a maximum 45 min a after floating them on a 100 ppm solution.Transplanting cuttings which had been rooted under mist was somewhat difficult; however, high rates of survival were obtained with cuttings planted in September which had developed a good root system.     

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.     

不同基质对聊红槐扦插生根的影响

以细河沙、草炭、珍珠岩:草炭=1∶1为扦插基质,用400 mg/L的IBA和NAA处理聊红槐插穗,进行春季硬枝扦插,测定其生根指标,筛选出适合生根的扦插基质.结果表明:以河沙为基质,经过IBA处理过的插穗的生根率较NAA处理的好;以草炭为基质,经过NAA处理过的插穗较IBA处理的好;以珍珠岩:草炭=1∶1为基质,经过IBA处理过的插穗较NAA处理的好;同一激素处理的根系效果,浸泡时间3h的优于1h处理的.     

A simple method for large-scale propagation of Dendrocalamus asper

The influence of position of cuttings, auxin treatments and seasonal variation on adventitious rooting of Dendrocalamus asper, a multipurpose edible bamboo of horticultural value, was examined. Single node proximal (culm) and distal (culm-branch) cuttings were collected during the months of April–June and treated for 24 h with water or 2 mM auxin (indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA)). The treated cuttings were planted horizontally in sand beds and maintained under misting conditions for 2 months. Culm cuttings exhibited better adventitious rooting than culm-branch cuttings and the month of May proved to be the best for rooting of both types of cuttings. Auxin treatments also influenced adventitious rooting and their effectiveness was in the order: NAA>IBA>IAA. The interaction among auxin, position of cuttings and month of collection was also found to be significant on root induction and differentiation. Single node culm cuttings, without auxin treatment, resulted in 98% plantlets in May and 67% plantlets in June, and emerged as a suitable material for large-scale vegetative propagation. Administration of IAA or NAA to abundant culm-branch cuttings of low commercial utility (collected in May) also produces ≥50% plantlets.     

Cloning of Ceylon olive (Elaeocarpus serratus L.) using conventional methods

Ceylon olive (Elaeocarpus serratus L.; family Elaeocarpaceae) is an under-utilised edible fruit tree that is sparsely distributed in the southern peninsula of the Indian sub-continent. Fresh and ripened fruit are edible and are used to prepare value-added products such as squash, jams and pickles. Methods to produce clonal E. serratus plants using softwood cuttings, air-layers, and grafts were investigated. Softwood cuttings were collected during the wet summer season (June–August) and showed 96.7% rooting success following 2.5 mM indole-3-butyric acid (IBA) treatment for 3 h. Hardwood cuttings collected during the wet summer season and subjected to IBA treatment failed to root. The duration of the auxin treatment significantly influenced the rooting percentage of softwood cuttings. Seasonal variations in the rooting response of softwood cuttings was also noted. The wet summer (June–August) was the best season for rooting softwood cuttings. Air-layers of hardwood branches, prepared during the wet summer season by pre-treating with 7.5 mM IBA resulted in 87.1% rooting. The spliced grafting technique could be applied also to elite Ceylon olive clones, with 70% and 50% survival rates of softwood and hardwood grafts, respectively. Ceylon olive could therefore be cloned by adopting these methods. Propagation based on softwood cuttings would facilitate moderate-scale cloning of this valuable, elite germplasm.     

三种生长调节剂对金边虎尾兰、月季与天竺葵扦插生根的影响

以金边虎尾兰、月季与天竺葵为试材,研究不同生长调节剂及其浓度对3种园林植物扦插生根的影响。结果表明:金边虎尾兰叶基段以100mg/L浓度的IBA或NAA扦插效果较好,叶尖段以IBA 100～200mg/L或NAA 200mg/L扦插效果较好,生根率均达到100%;100～200mg/L浓度的IBA与100mg/L浓度的NAA对月季茎插生根效果较好,生根率达75.6%～77.8%;天竺葵茎插各处理的生根率均达到100%,但从平均生根数上比较,100mg/L NAA或25mg/L IBA对其扦插生根效果最佳,25～300mg/L的IAA对其生根数有抑制作用。     

Effect of nitrogen nutrition of stock plants of Justicia gendarussa L. on the rooting of cuttings

The effect of the nitrogen nutrition of stock plants of Justicia gendarussa L. on the rooting of cuttings was studied in sand culture under high, medium and low levels of nitrogen.

Nitrogen starvation induced rooting. Exogenous application of the auxins IAA (indol-3yl-acetic acid), IBA (indol-3yl-butyric acid) and NAA (naphth-lyl-acetic acid) greatly increased the rooting response of cuttings from-stock plants grown with small amounts of nitrogen.

The root-promoting effect of a low nitrogen supply was associated with a retardation of growth in the stock plants from which the cuttings were made. High C/N (total available carbohydrates/total nitrogen) and P/N (total phosphorus/total nitrogen) ratios increased anthocyanin pigmentation in the shoot, and increased rooting cofactor activity in the tissues of cuttings. The phenolic compounds, ferulic acid, p-hydroxybenzoic acid and p-coumaric acid were present in the shoots of all three nutritional treatments and acted as important cofactors in the cuttings. In general, rooting cofactor activity was inversely related to nitrogen supply and the activity was highest under low nitrogen.

The cuttings taken from plants grown under different levels of nitrogen interacted differentially with the exogenously applied auxins.     

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。     

5个矮生牡丹品种黄化嫩枝扦插技术研究

 研究了牡丹矮生品种‘银粉金鳞’、‘蓝田玉’、‘金玉交章’、‘小胡红’和‘石原白’黄化嫩枝扦插繁殖的关键环节和影响因素。结果表明, 该5 个品种黄化嫩枝生根率依次为91.0%、80.9%、78.6%、40.6%、20.0%; 于10月中旬截取长4～6 cm、基部直径0.5 cm以上的黄化嫩枝, 将形态学下端浸泡在20～25℃的IBA 100 mg/L或‘ABT 2号’150 mg/L中16 h, 扦插于粒径3～4 mm的蛭石基质里,‘银粉金鳞’插穗的生根率最高, 达93% , 且不定根健壮、上盆栽培生长良好。     

A comparison of conventional cloning options for annatto (Bixa orellana L.)

Summary

Annatto (Bixa orellana L.) is a tree indigenous to tropical America that has been naturalised throughout the Indian sub-continent. The plant is chiefly valued for its carotenoid pigments, annatto. Methods for the clonal propagation of hardwood and softwood cuttings, air-layering, budding, and grafting of annatto were investigated. Hardwood cuttings collected during the wet Summer months (June-July) were treated with indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), or naphthaleneacetic acid (NAA) at varying concentrations. The highest percentage rooting (63.4%), along with highest number of roots (8.33 per cutting) were achieved by hardwood cuttings after 12 h of 2.5 mM IAA treatment. Among the various auxin treatments of softwood cuttings, 5.0 mM IBA in combination with 5.0 mM NAA for 5 min resulted in a significant (P < 0.05) rooting percentage (56.7%). The responses of softwood cuttings to an auxin analogue (boric acid) and/or to thiamine hydrochloride (vitamin B) were inferior to synthetic auxins. When subjected to air-layering, hardwood branches gave 100% rooting without any application of hormone. Among the different types of budding methods attempted (patch, T, or I), patch budding produced the highest efficiency (78%) of propagation. Splice-grafting could also be used for conventional propagation of annatto, with a 50% survival rate. Annatto can therefore be cloned by adopting these methods. Propagation based on softwood cuttings facilitated moderate-scale cloning of this valuable, elite germplasm.     

The Influence of Source and Growth Substance on the Behaviour of Apple and Plum Cuttings

The behaviour of hardwood cuttings is influenced by factors that have operated upon the parent plant. A comprehensive study, not only of such " source ” effects but also of their interaction with growth substance treatment and subsequent environment, aims to extend this method of propagation. Patterns of behaviour of varieties of very different rooting capacity are clearly related, layer cuttings being better than hedge, with a declining gradient from the base of the shoot. The etiolated basal cutting from a layer shoot normally roots well whenever planted, but non-etiolated cuttings derive considerable benefit from over-wintering in soil.

With the readily rooting Myrobalan B, growth substance application in the autumn is not essential ; such treatment is advocated for the moderately rooting Brompton plum while, with the shyly rooting Crab C, accelerative influence has, so far, proved inadequate. Success with Crab C could derive from the ability of the cutting to survive, though unrooted, into the second year when rooting normally follows. Spring planting and absence of growth substance stimulation enhance this chance.

Brompton cuttings have medium power to survive, whereas Myrobalan B cuttings have only low, so that they are liable to succumb when conditions are adverse. The survival factor may contribute considerably towards the rooting gradient and must be distinguished from inherent rooting capacity.

When the rooting of non-etiolated cuttings is satisfactory the relative disparity of hedge compared with layer cuttings diminishes, and hedge culture is highly favoured for supplying cuttings.

Elevation of hitherto shy-rooting varieties to high levels depends upon further adjustment both of growth substance treatment and subsequent environment.     

Interaction of stock plant irradiance and auxin in the propagation of apple rootstocks by cuttings

The purpose of the investigation was to examine the effects of different irradiances (light intensities: 8, 16, 38, 54 W/m²) to stock plants on the subsequent rooting of cuttings taken from these stock plants.If the cuttings were rooted without treatment with auxin (indole butyric acid), there was no difference in rooting attributable to the irradiance pretreatments. Auxin treatment of the cuttings was most effective in increasing root numbers and rooting-percentage in cuttings taken from stock plants grown under 8 W/m².     

三唑酮与乙蒜素混剂对变叶木插穗生长的影响

用三唑酮6．25％＋乙蒜素93．75％混合配制成160mg／L至1600mg／L10种不同浓度的药剂，分别对变叶木插穗浸泡处理后扦插。试验结果表明，最佳处理的插穗生根数、根长、根径的平均值和最高成活率分别为45．2、31．8、1．47、80％，分别比对照提高了9．6、7．4mm、0．36mm、46．67％，所测指标均与对照的差异极显著（P〈0．01）。在160-400mg／L范围，处理浓度与插穗的生根数、根长、根径以及成活率的关系符合二次曲线模型（R2〉0．97）；统计分析结果，处理3h的最佳浓度为291mg／L。     

Contributions of the leaves and axillary shoots to rooting in Eucalyptus granáis Hill ex Maid,stem cuttings

In one-node stem cuttings of Eucalyptus granáis the absence of leaves was fatal. The optimum leaf area per leaf for rooting was 2-5 cm2, and in this range rooting was higher in one-leaf than in two-leaf cuttings. Axillary shoots started to develop soon after the cuttings were set and their growth was promoted by the presence of the subtending leaf. Thus, in one-leaf cuttings the shoot in the leafy axil grew, at the expense of the shoot in the defoliated axil, while in two-leaf cuttings the shoot in the upper (sub-opposite) axil tended to grow more quickly. Axillary shoots were also vigorous in cuttings from decapitated and disbudded mother plants. Rapid shoot growth was associated with low rates of abscission of the subtending leaf and relatively high rooting ability. Removing axillary shoots from cuttings accelerated leaf abscission and reduced rooting. The stem of the cutting often swelled and discoloured from the base, apparently due to the demand of the cutting for water. Additional leaf wounds had no effect on rooting (but increased mortality), while immersing cuttings in water before setting, or leaving them in a loose heap on the propagation bench, promoted rooting.     

Stock plant shading and rooting of dahlia cuttings

The effect of shading dahlia mother plants on rootability of cuttings was studied with three cultivars: ‘Choot Hashani’, ‘Orpheo’ and ‘Lavender Perfection’. Reducing natural light intensity by approximately 50% increased rooting percentage of ‘Orpheo’ cuttings, but did not affect rooting of the harder cuttings of ‘Lavender Perfection’. Shading stock plants during midday hours only caused internode elongation in ‘Orpheo’, but did not increase rooting. In ‘Choot Hashani’ the same shading treatment promoted rooting. Shading only the base of the cutting when still on the mother plant greatly promoted rooting percentage and mean number of roots per cutting. The reason for the variability in the response to shading is discussed and it is concluded that the shading effect is limited to the root initiation region. It is assumed that shading improves rooting by promoting the herbaceous character of the rooting region. Shading did not affect rooting of cuttings which remained woody in spite of shade.     

Effect of acid or base pretreatment on auxin response of Damask rose cuttings

Hardwood stem cuttings of Damask rose (Rosa damascena Mill.) were dipped in H₂SO₄ or NaOH prior to application of 0, 1000, 2000 or 3000 mg l⁻¹ indolebutyric acid (IBA) or naphthaleneacetic acid (NAA). Acid pretreatment significantly increased root number, root length and root dry weight per cutting, but did not affect rooting-percentage. Rooting was significantly enhanced by auxin pretreatment, and NAA was superior in increasing root length and root fresh weight; 2000 mg l⁻¹ of auxin was the most suitable concentration for promotion of rooting under the conditions of the study.