scholarly journals Low pH Enhances Rooting of Stem Cuttings of Rhododendron in Subirrigation

1998 ◽  
Vol 16 (1) ◽  
pp. 4-7
Author(s):  
Thomas A. Holt ◽  
Brian K. Maynard ◽  
William A. Johnson

Abstract Semi-hardwood terminal stem cuttings of Rhododendron L. ‘P.J.M.’, R. ‘Catawbiense Album’ and R. ‘Purple Gem’ were treated with a solution of 0.1% indolebutyric acid and 0.5% napthaleneacetic acid and inserted into perlite for rooting under subirrigation, without overhead mist, at solution pH of 4.5 or 7.5. All cultivars rooted in higher percentages and produced larger root balls at pH 4.5 than at pH 7.5. A second study with softwood stem cuttings of R. ‘P.J.M.’ and both softwood and semi-hardwood stem cuttings of R. ‘Purple Gem’ confirmed these findings and included an additional subirrigation treatment, a sphagnum peat slurry, pH 4.1, which produced nearly identical results to the pH 4.5 treatment.

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 983D-983
Author(s):  
Christopher B. Cerveny ◽  
James L. Gibson

Bougainvillea glabra is a tropical species with reportedly difficulty to propagate. Previous research has shown the importance of talc-based rooting hormones when propagating Bougainvillea, yet little has been published on the efficacy of liquid-based formulations. Therefore, our objective was to determine the optimum concentration of indolebutyric acid potassium salt (KIBA) needed to effectively root semi-hardwood stem cuttings of Bougainvillea `California Gold' and `Helen Johnson'. Sub-terminal cuttings measuring 6.5 cm were harvested from stock plants of Bougainvillea on 3-week intervals from 6 June to 8 Aug. and repeated 6 Sept. to 8 Nov. 2005. Cuttings were dipped 0.5 cm in a solution of 0, 1500, 3000, or 6000 mg·L-1 KIBA or in a 1500-mg·L-1 solution containing indolebutyric acid (IBA) 1%: napthaleneacetic acid (NAA) 0.5% and propagated under mist. Cuttings were evaluated for percent survival, rooting quality (1 = poor; 5 = best), and number of primary and lateral roots 5 weeks after planting (WAP). Differences in `California Gold' for percent survival, average rank, and number of roots were determined not significant at P ≤ 0.05. However, application of rooting hormone to `Helen Johnson' increased rooting quality, number of primary roots, and number of lateral roots by up to 24%, 53%, and 50%, respectively. Results indicated rooting performance was generally improved with application of KIBA; therefore, cuttings of Bougainvillea may benefit from a 1500-mg·L-1 solution. KIBA was also found to be as effective as the industry standard liquid formulation. Growers will have to consider the availability and cost of KIBA when propagating Bougainvillea.


2000 ◽  
Vol 51 (1) ◽  
pp. 23 ◽  
Author(s):  
V. P. Ila'ava ◽  
C. J. Asher ◽  
F. P. C. Blamey

Sweet potato [Ipomoea batatas (L.) Lam.] is cultivated on soils varying widely in chemical properties, but relatively little is known about the effects of pH on the growth of this crop. In commercial and subsistence agriculture, sweet potato is propagated mostly from stem cuttings. This paper reports effects of a range of pH treatments (3.5–8.0) in flowing solution culture on early growth from cuttings of 15 sweet potato cultivars. Root growth was either greatly reduced or inhibited at pH 3.5. Increasing the pH to 4.0 markedly increased root development. Further increases in solution pH from 4.0 to 8.0 did not appear to affect root growth in most cultivars. Top growth in most cultivars showed a tendency to increase when pH was increased from 3.5 to 5.5 before declining with further increases in solution pH. The sweet potato cultivars studied differed widely in their tolerance to low pH, producing 16–48% of maximum top dry mass at pH 3.5. Tissue analysis from selected cultivars showed that K and Ca appeared to be limiting at pH 3.5, while P may have been deficient at pH 8.0. Results of this study indicate that low pH per se does not appear to be a major factor responsible for poor sweet potato yields in acid soils.


HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 500F-501
Author(s):  
Christopher B. Cerveny ◽  
James L. Gibson ◽  
James E. Barrett

Orange Jasmine (Murraya paniculata L. Jack) and Texas Star [Tecoma stans (L.) Juss.] are two tropical ornamentals which have become popular in the specialty floriculture crop market because of their outstanding flower characteristics. Unfortunately they are difficult to root and little has been published on how to propagate them effectively. Therefore, the objective of our experiment was to determine the optimum physiological age of stem tissue necessary to effectively root 2-node stem cuttings. Forty-five cm shoots of Murraya were harvested on 27 June and 7 Sept. 2005, and divided into 2-node stem cuttings representing the top, middle, and bottom sections of the stem (soft-wood, semi-hardwood, and hardwood, respectively). Cuttings were measured for stem length and diameter, dipped in a 1,500 mg·L–1 solution containing indolebutyric acid (IBA) 1%: napthaleneacetic acid (NAA) 0.5%, and propagated under mist for 10 weeks in a 4 perlite: 1 vermiculite substrate (by volume). Tecoma followed a similar regime but were harvested once on 13 Sept. and evaluated 4 weeks after planting. Both species were evaluated for percent survival and rooting quality on a 1 to 5 scale; 1 = poor, 5 = best. Stem quality differences in Tecoma cuttings were shown, but did not influence rooting performance or percent survival. Murrayacuttings indicated a similar trend suggesting that age of tissue is not an important factor when propagating these species. However, when comparing the two harvest dates, data from Murraya cuttings showed an increase in survival from 79% and 95% and an increase in rooting quality from 2.72 to 4.26 when harvested in June compared to Sept., respectively. Cuttings harvested in Sept. were also shown to be 17% shorter with a 126% larger diameter than those harvested in June. These data suggest a trend toward a seasonal effect when harvesting cuttings of Murraya paniculatain Florida. Further studies should be conducted to verify this trend and to identify the ideal season for propagation.


1969 ◽  
Vol 47 (4) ◽  
pp. 280-289
Author(s):  
W. Pennock ◽  
G. Maldonado

1. A highly successful propagation method is described by which hundreds of side-sprouts are first induced on the parent guava tree. These are later cut and rooted under alternatmg mist, with leaves attached. By using this method it is possible to produce from 500 to 1,000 guava plants from a single 3-year-old tree within 10 months. 2. An experiment is also described and discussed which showed that different rooting media, such as coarse sand and very fine gravel, with Coco-peat, fir bark, Vermiculite, Perlite, and Mexifern, had no appreciable effect on rooting. But treatment with a relatively high concentration, 200 p.p.m., of indolebutyric acid improved and accelerated rooting markedly. Rooting was still further improved if 2 percent of sugar was combined with the indolebutyric acid treatment. 3. The high susceptibility of cuttings under mist to anthracnose disease is mentioned and the usual course of the disease described. Recommendations are suggested for reducing the incidence of this disease.


1990 ◽  
Vol 41 (5) ◽  
pp. 933 ◽  
Author(s):  
MA Ewing ◽  
AD Robson

The study tested the hypothesis that annual medic species which nodulate well in acid soils in the field (M. murex Willd. and M. polymorpha L.) will nodulate better in acid solutions with low calcium concentrations than annual medics which nodulate poorly in acid soils (M, truncatula Gaertn.). Effects of pH (5.5 and 6.5) and calcium concentration (0.2, 0.5, 1 and 2 mM) on the early growth and nodulation of three annual medic species (M. truncatula, M. polymorpha and M. murex) were investigated. Increasing pH or calcium concentration did not increase plant growth for any of the species. However, nodulation was generally depressed by low pH for all species. Increasing calcium concentration in solution increased nodulation in all species. Effects of low pH and low calcium concentration in decreasing nodule number were much greater for M. truncatula than for M. polymorpha and M. murex. At pH 5.5, M. truncatula failed to nodulate at any calcium concentration, whereas a large proportion of M. murex plants nodulated at 1 mM calcium and some M. polymorpha plants nodulated at 2 mM calcium. At pH 6.5, M. polymorpha required 1 mM calcium in solution for maximum nodule number, and M. murex only 0.5 mM calcium, whereas nodule number for M. truncatula increased up to 2 mM calcium, the highest concentration used. The results provide the basis for a simple screening system to distinguish differences among annual medics in nodulation tolerance to acidity. The maintenance of ranking among species with respect to nodulation over a wide range of stresses induced by combinations of low pH and calcium concentration suggest that screening using a single stress combining these two components would be adequate. Nodulation differences between species can be simply and effectively assessed using a scoring system combining number size and location of nodules.


Revista CERES ◽  
2015 ◽  
Vol 62 (3) ◽  
pp. 284-293 ◽  
Author(s):  
Lílian Estrela Borges Baldotto ◽  
Marihus Altoé Baldotto ◽  
Matheus Pereira Simões ◽  
Reges Rodrigues de Oliveira ◽  
Hermínia Emília Prieto Martinez ◽  
...  

The vegetative propagation of ornamental plants can be accelerated by applying plant growth regulators. Amongst them, the use of auxins, plant hormones with physiological effects on cell elongation and rooting have stood out. Alternatively, the application of humic acids, bioactive fraction of soil organic matter, also results in increases in rooting cuttings of ornamental plants. The objective of this work was to study the growth characteristics and the nutritional contents of croton and hibiscus plants during acclimation of seedlings in response to different concentrations of indolebutyric acid (IBA) and humic acid (HA) applied to cuttings for rooting. The experiment was conducted in greenhouse, and the apical stem cuttings were treated with solutions with concentrations of 0, 250, 500, 1000 and 2000 mg L-1of IBA and 0, 10, 20, 30 and 40 mg L-1 of C from HA. At 45 days of rooting in carbonized rice husk, they were individually transferred to plastic bags of 2.0 dm3 containing a mixture of soil: sand: manure (2: 1: 1) as substrate. At 90 days of acclimation, the plants were collected for measurement of growth and nutritional variables. The results showed that the application of the IBA stimulates the absorption of nutrients and growth of croton cuttings and transplanted hibiscus, contributing to formation of vigorous seedlings. A similar response occurred with the application of HA in hibiscus cuttings


1991 ◽  
Vol 39 (2) ◽  
pp. 179 ◽  
Author(s):  
C Blomstedt ◽  
J Cameron ◽  
P Whiteman ◽  
SF Chandler

Node-derived shoot cultures of Eucalyptus regnans were established from in vitro grown seedlings on Murashige and Skoog basal medium supplemented with 0.5 mg L-1 (2 μm) zeatin and 0.05 mg L-1 (0.3 μm) napthaleneacetic acid. A double sterilisation method was essential to obtain clean material from seed. Microcuttings from established cultures were used to develop an efficient method for in vitro rooting. Rooting was best after a 7 day pulse on 20 mg L-1 (98 μm) indolebutyric acid. Hoagland's or Woody Plant Medium supported better rooting than MS basal medium and rooting was significantly enhanced by subculture to activated charcoal after the auxin pulse. Carbohydrate (sucrose or glucose) was essential for rooting while high light intensity was inhibitory. Optimal light conditions were a 12 h day (17 W m-2). In all, 90% of plantlets established in the nursery survived the winter.


2006 ◽  
Vol 24 (3) ◽  
pp. 124-128
Author(s):  
L. Eric Hinesley ◽  
Frank A. Blazich ◽  
Scott A. Derby

Abstract Stem cuttings of Leyland cypress [x Cupressocyparis leylandii (A.B. Jacks. & Dallim.) Dallim. & A.B. Jacks], were rooted to determine the effect of A) date of collection, rooting substrate, and mist frequency, B) auxin formulation and concentration, C) rooting substrate, D) substrate fertility, and E) type of cutting and auxin concentration. Results were best for misting intervals of 5 to 7 min during the day, but 10 min was also adequate. Rooting was comparable for softwood cuttings collected in late May or late June. Powder and liquid auxin formulations, which both contained indolebutyric acid (IBA), yielded similar results. Cuttings that were more lignified (light tan color) at the bases benefited the most from higher concentrations [≈ 8000 ppm (0.8%)] of IBA in talc, whereas less mature cuttings (green at the bases) rooted in highest percentages with lower concentrations [≈ 3000 ppm (0.3%)]. Rooting was similar in substrates with a peat:perlite ratio (v/v) of 1:1, 1:2, or 1:4, whereas results were less satisfactory in 100% perlite. Controlled release fertilizer [1.8 kg/m3 (4 lb/yd3)] in the rooting substrate did not affect rooting percent, but greatly increased root mass and quality of rooted cuttings. Doubling the rate resulted in little additional improvement. Rooting was comparable for vigorous side shoots (1st-order laterals) and tips from vigorous upright branches (primary axes) of similar maturity.


2003 ◽  
Vol 21 (2) ◽  
pp. 61-63
Author(s):  
Peter J. Conden ◽  
Frank A. Blazich

Abstract Two experiments were conducted to develop a protocol for propagation of Castanopsis sclerophylla (Lindley & Paxton) Schottky by stem cuttings. In the first experiment completed in 2000, stem cuttings were taken on three dates representing three growth stages (softwood, semi-hardwood, or hardwood). Semi-hardwood and hardwood cuttings were treated with 0, 2500 (0.25%), 5000 (0.5%), 7500 (0.75%), or 10,000 (1.0%) ppm of the free acid of indolebutyric acid (IBA) dissolved in 50% isopropyl alcohol, whereas softwood cuttings were treated with the same concentrations of the potassium (K) salt of IBA (K-IBA) dissolved in distilled water. Cuttings were placed in a raised greenhouse bench and rooted under intermittent mist. Cuttings taken at the semi-hardwood and hardwood stages began to drop their leaves after approximately 2 weeks and the majority eventually died, with negligible rooting of surviving cuttings. The response of the softwood cuttings to K-IBA was quadratic with the greatest rooting (63%) at 7500 ppm K-IBA. Seventy softwood cuttings that rooted were potted for observance of overwinter survival. Of these, 90% produced a flush of growth during the summer, with 80% overwinter survival. In the second experiment conducted in 2001, semi-hardwood cuttings were taken and treated with 0, 2500 (0.25%), 5000 (0.5%), 7500 (0.75%), or 10,000 (1.0%) ppm K-IBA and placed in a raised greenhouse bench with intermittent mist for rooting as in the first experiment. Results were similar to the semi-hardwood cuttings treated in the first experiment with the free acid of IBA, indicating semi-hardwood cuttings do not root and that the auxin and/or isopropyl alcohol were not toxic to the cuttings.


1985 ◽  
Vol 3 (2) ◽  
pp. 65-68
Author(s):  
William H. Gensel ◽  
Frank A. Blazich

Two experiments were conducted to determine the feasibility of propagating Chapman's rhododendron (Rhododendron chapmanii A. Gray) by rooting stem cuttings. In the first experiment, semi-hardwood terminal cuttings taken from native plants, rooted in moderate percentages (43 to 63%) with the percentage of commercially acceptable cuttings (cuttings having a distinct root ball) being less (22 to 53%). The second experiment used hardwood terminal and subterminal cuttings taken from containerized stock plants that originated from cuttings rooted in the first experiment. Percent rooting for total and commercially acceptable cuttings ranged from 81 to 94% and 39 to 64%, respectively. For both experiments, indolebutyric acid (IBA) treatments resulted in an increase in the percentage of commercially acceptable cuttings.


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