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.     

Nitric oxide in combination with indole-3-butyric acid improves root growth in ‘Ferdor Julior’ hardwood cuttings (Prunus insistitia (L.) × Prunus domestica (L.))

The production of plants for high density fruit orchards requires a highly efficient clonal propagation method. ‘Ferdor Julior’ rootstock is well adapted to different soil conditions, but its natural rooting potential is very limited. Propagation treatments, such as bottom heat and indole-3-butyric acid (IBA) applications have previously been used to improve rooting. The aim of this work is to evaluate the effects of either IBA, or sodium nitroprusside (SNP; a nitric oxide (NO) donor), or a combination of both on the rooting of hardwood cuttings of ‘Ferdor Julior’. As metabolism markers, ascorbic acid (AA) and glutathione (GSH) were measured in adventitious roots. ‘Ferdor Julior’ hardwood cuttings were treated as follows: untreated, 0.3 mM IBA, 1 mM SNP, 1 mM SNP previously exposed to light (as a negative control), and 1 mM SNP + 0.3 mM IBA. After 4 months, the combined use of SNP and IBA had increased root growth and lateral rooting, but resulted in less shoot growth, whilst AA and GSH concentrations were also reduced. IBA and SNP individual treatments showed intermediate results, compared to untreated cuttings. According to the results obtained, there may be an additive effect of auxin and NO signaling pathways. In conclusion, this new and promising technique for ‘Ferdor Julior’ propagation could improve lateral root development and promote early lateral root growth.     

Black Currant Leaf Spot: II. Laboratory Tests of Fungicides for the Prevention of Sporing of Pseudopeziza Ribis on Overwintered Leaves

Summary

We have developed a two-step procedure for rooting of tea microshoots in vitro. The effectiveness of different auxin treatments for root formation was found to differ. Among the auxins tested, 25 μM -naphthalene acetic acid (NAA) gave the best results, with 100% rooting, compared to 25 μM indole-3-butyric acid (IBA) or 25 μM indole-3-acetic acid (IAA), which induced 17% and 58% rooting, respectively. Incubation of tea microshoots on 0.33 Murashige and Skoog (MS) medium, supplemented with 25.0 μM NAA or 175.0 μM IBA for 10 d, followed by transfer to auxin-free 0.33 MS medium resulted in 100% rooting, whereas 50.0 μM IAA induced 91.7% rooting. Besides the different auxin treatments, the strength of the MS medium, the duration of incubation of microshoots in auxin-containing medium, the sucrose concentration, the gelling agent, the pH of the medium, the incubation temperature, the light intensity, and the quality of the shoots also played a significant role during in vitro rooting of micropropagated tea shoots. Among the combinations tested, the most effective results were obtained when green microshoots were incubated on 0.33 MS medium supplemented with 25.0 μM NAA, 50.0 mM sucrose, pH 5.5, gelled with 0.2% (w/v) Phytagel^TM for 10 d at 25° – 30°C at a light intensity of 40 μmol m^–2 s^–1, followed by transfer of shoots to auxin-free 0.3 MS medium. This resulted in 100% rooting and, on average, 11 long roots were formed per shoot. Anatomical changes during adventitious rooting of micropropagated tea shoots in vitro were also studied to understand the process of rooting.     

Rooting-enhancement of Rosa hybrida for tissue culture propagation

The effect of combinations of auxin sources and concentrations, temperature shifts, light intensity and light reduction on shoot-tips were studied relative to root formation of Rosa hybrida L. ‘Bridal Pink’ propagated in vitro. 2,4-dichlorophenoxyacetic acid alone was almost ineffective, and similarly its combinations with other auxins were less effective than other auxin combinations. While indolebutyric acid (IBA) alone did not stimulate rooting, both indoleacetic acid (IAA) and naphthaleneacetic acid (NAA) were effective. Combinations of NAA and IBA and NAA and IAA were equally effective in stimulating rooting and also enhanced rooting more than IAA, IBA or NAA alone. When root quality is considered, the combination of NAA and IBA was better than that of NAA and IAA.An additive effect on rooting existed between NAA and IAA at most concentrations used. A similar effect was evident between NAA and IBA except when NAA was used at 0.025 mg/l, in which cases synergistic effects were observed. Light reduction to the rooting area, light intensities of 1.0 K lux or lower and holding the cultures for 1 week at 5°C all enhanced rooting.     

不同基质与植物生长调节剂对扶桑插条生根的影响

研究了珍珠岩、蛭石、河沙、菜园土、腐殖营养土等不同基质配比、不同生长素调节剂(IBA、IAA、NAA)及其浓度、生长调节剂与多效唑(PP333)混合使用对扶桑插条生根的影响。结果表明:河沙+腐殖营养土等体积混合的基质对生根的效果最好;IBA处理的生根效果较好,其中以IBA 150mg/L处理的生根率最高,为93.67%;IAA的处理中,以低浓度50mg/L的生根率最高,为90.67%;较高浓度NAA的处理平均生根数较多,但生根率较低。用含PP33320mg/L与IAA 50mg/L或与IBA 150mg/L的混合液处理均能提高扶桑插条的生根效果。     

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。     

几种植物生长调节剂对山茶花扦插生根的影响

应用不同浓度的IAAI、BA、NAA及IAA+NAA与IBA+NAA组合液对4种山茶进行硬枝扦插研究。结果表明:植物生长调节剂对山茶插条都具有促进生根作用;5种生长调节剂中,IBA的促根效果最好;单独使用时,150 mg/L的IAA1、00 mg/L的IBA或NAA1、50 mg/L的IAA+NAA(1∶1混合)与IBA+NAA(1∶1混合)处理对山茶花扦插生根促进效果最好。     

Differentiation of the dynamic variables affecting rooting ability in juvenile and mature cuttings of cherry (Prunus avium)

Summary

The rooting potential of four types or origins of Prunus avium cuttings from the same mature trees (over 20 years-old) was compared using a mist propagation bed during early Summer (June). The cuttings originated from juvenile sucker shoots of the current and previous year, and mature crown shoots (current year’s lateral ‘long-shoots’ and multi-year terminal ‘short shoots’). The morphological differences in inter-node length, stem diameter and leaf area between the four cutting types were highly significant (P = 0.05), leading to large differences in cutting volume and, so it is argued, to assimilate reserves. Juvenile cuttings rooted well (65% and 77% rooting for hardwood and softwood shoots, respectively), while mature cuttings rooted poorly (4% and 7% for mature hardwood and softwood cuttings, respectively). Leaf abscission was significantly more frequent in mature hardwood cuttings (16 – 78%) than in the other cutting types (1.6 – 9%) at the end of the propagation period. Leaf loss resulted from two processes: abscission and leaf rotting. Physiologically (i.e., in carbon assimilation, leaf transpiration and stomatal conductance), the four cutting types were not significantly different early in the post-severance period (day-4); but, by day-22, stomatal conductance was lowest in mature hardwood cuttings that still had leaves. At this time, the most physiologically-active unrooted cuttings were from juvenile hardwood and mature softwood shoots. The extent of physiological and morphological variability between cutting types and their probable impact on processes affecting rooting ability is complex and highly interactive. Consequently, it is not possible to explain the causes of the variation in rooting ability between juvenile and mature cuttings, although this study suggests that the constraints to rooting are likely to reflect physiological differences between the different cutting types. It is concluded that, to resolve the debate about factors that affect the rooting ability of juvenile and mature cuttings (i.e., ontogenetic vs. physiological ageing), there is a need to achieve morphological and physiological comparability in the tissues.     

IBA和发根农杆菌对糠椴嫩枝扦插的影响

 研究了IBA和发根农杆菌处理对糠椴嫩枝扦插生根的影响, 并对其影响生根的机理进行了初步探讨。结果表明: IBA和发根农杆菌处理显著( P < 0.01) 提高了插条生根率, 增加了成活苗的生根数和根长, 明显缩短了生根时间。IBA和发根农杆菌处理还显著( P < 0.01) 提高了插条生根期内源GA₃和IAA、可溶性总糖和全氮的含量及IAA /ABA比值, 降低了ABA含量, 对糠椴嫩枝扦插生根有明显的促进作用, 其中以500 mg·kg^-1 IBA +发根农杆菌处理的生根效果最好, 插条的生根率、成活苗的生根数、成活苗的根长分别比对照增加了122.08%、65.75%和23.63% , 生根时间比对照缩短了14 d。     

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.     

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.     

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.     

In vitro adventitious rooting of Cornus florida microshoots

Cornus florida L. (flowering dogwood) has been successfully micropropagated, but low rooting of microshoots makes the system inefficient. This study was conducted to increase rooting efficiency of flowering dogwood microshoots over that previously achieved. Microshoots originating from acclimatized axillary and nodal bud stock cultures were excised and treated with different concentrations and combinations of various auxins including indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA). Effect of microshoot age on rooting efficiency was also examined. Of the auxins tested, maximum rooting was observed with 4.4 μM IBA. The age of microshoot explants had a significant effect on rooting. Five to seven-week-old microshoots treated continuously with 4.9 μM IBA in Woody plant medium (WPM) consistently had the best and most consistent rooting efficiency (about 83%).     

同源四倍体玫瑰香葡萄嫩枝扦插不定根发生过程中内源激素的变化

 以葡萄同源四倍体玫瑰香和其二倍体玫瑰香母株的嫩枝插条为试材, 研究了扦插生根过程中(0～18 d) 生根部位皮层的内源激素含量变化。结果表明: 玫瑰香葡萄同源加倍以后, 不仅改变了不同时期插条生根部位皮层的内源激素水平, 也改变了该部位对外施NAA的反应。在不定根诱导期( 0～3 d) ,促进生根的生长素水平下降, 抑制生根的脱落酸和赤霉素含量上升, 生长素与脱落酸和赤霉素的比值下降;应用NAA处理以后, 在根原基诱导期(0～3 d) , 赤霉素、玉米素和玉米素核苷含量不降反升, 改变了内源激素的整体变化态势。分析认为, 同源加倍后嫩枝插条生根部位内源激素的代谢变化是造成其生根能力降低的主要原因之一。     

金丝小枣扦插繁殖及其生理机制研究

幼化(复壮)插条和成年枣树嫩枝插条经NAA处理后发现,幼化插条扦插后15d内已经有根原基形成和分化;成年插条只形成了愈伤组织并不断增大,没有形成根。幼化插条在扦插后9d内源IAA含量达到最高值;成年插条内源IAA含量升高,但一直维持在较低水平。在扦插后第9天、12天,前者的ABA含量低于后者,差异达到显著水平。幼化插条的过氧化物酶活性、IAA氧化酶活性均低于成年插条。扦插后,二者的过氧化物酶同工酶谱带也产生了差异。     

Micropropagation and accumulation of essential oils in wild sage (Salvia fruticosa Mill.)

A protocol for in vitro propagation of the wild three-lobed sage (Salvia fruticosa Mill.) (Synonym, Salvia triloba L.) was developed. Shoot tips were excised from in vitro seedlings and established on MS, Nitch and Nitch (NN), or B5 medium. For shoot proliferation, in vitro nodal and apical explants were cultured on MS medium containing 0.25–2 μM 6-benzylaminopurine (BA), 6-furfurylaminopurine (kinetin), or thidiazuron (TDZ). Proliferated microshoots were rooted on MS medium supplemented with 2.7–11.4 μM indole-3-butyric acid (IBA), indole-3-acetic acid (IAA), or α-naphthaleneacetic acid (NAA). Results indicated that shoots established at 100% regardless of media type, however, shoot height, nodes per shoot, and leaf number were highest for explants established on MS medium compared to NN or B5. Number and height of proliferated shoots, nodes per shoot, and leaf number were highest for nodal explants cultured on a medium containing 0.75 μM BA. Microshoots cultured on a medium supplemented with 2.7 μM IBA exhibited the highest rooting percentage compared to those cultured with IAA or NAA. Essential oil composition in microshoots and shoots of greenhouse-grown plants was determined by gas chromatography/mass spectrometry. The major essential oils detected in both plant materials were α-pinene, 1,8-cineole, camphor, and borneol. No α-thujone or β-thujone was detected. The content of essential oils, camphor, and borneol were higher in the microshoots than in shoots of greenhouse-grown plants.     

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.     

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.     

Factors affecting tissue culture of Damask rose (Rosa damascena Mill.)

The present study was conducted to evaluate the regeneration ability of Damask rose. Single-node explants were surface sterilised with 10% chlorox for 15 min and cultured on Murashige and Skoog (MS) medium supplemented with various concentrations of N⁶-benzyladenine (BA) or kinetin (Kin) separately or in combination with different concentrations of indole-3-butyric acid (IBA). Combination of 2.5–3 mg/l BA and 0.1 mg/l IBA was the most suitable treatment for proliferation. In vitro derived shoots were subcultured four times on the fresh medium within a 4-week period. Other treatments such as explant orientation (horizontal, vertical and oblique) and explant wounding were also examined but did not affect shoot multiplication rate significantly. Several experiments were carried out to stimulate in vitro rooting of Damask rose. Application of different media such as MS, 1/2 MS, 1/3 MS and 1/4 MS with different concentrations of indole-3-acetic acid (IAA), IBA and naphthaleneacetic acid (NAA) did not produce satisfactory results. Quick-dip method using sterilised 0–2000 mg/l IAA, IBA and NAA solutions was also studied. Other treatments such as using various concentrations of abscisic acid (ABA) in combination with various concentrations of IAA, IBA and NAA, and using various concentrations of sucrose and agar did not produce any roots. The best treatment for rooting of shoots was 2.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) for 2 weeks in MS medium and then transferring the explants to MS medium without any growth regulator. Plantlets were acclimatised in a soil mixture consisting of peat moss and sand 1:1 (v/v) and successfully transferred to the greenhouse after 3 weeks.