Mean Number Of Roots Research Articles

Rooting Woody Stem Cuttings in Grape Pomace Media Amended with Composted Bark, Perlite or Peat

Terminal stem cuttings of seven woody nursery species [boxwood (Buxus sempervirens L. `Green Mountain'), coralberry (Symphoricarpus × chenaultii Rehd. `Hancock'), lilac (Syringa velutina Kom.), Peegee hydrangea (Hydrangea paniculata Siebold. `Grandiflora'), purple-leaf sandcherry (Prunus × cistena N.E. Hansen), Rose-of-Sharon (Hibiscus syriacus L. `Lucy'), and winged spindle-tree (Euonymus alata Thunb.) Siebold. `Compacta')] were rooted under outdoor lath (50% shade) and mist in leached rooting media consisting of 0, 20, 40, 60 and 80% by volume of 2-year-old grape pomace amended in binary mixtures with sphagnum peat, perlite or composted bark. Rooting performance, expressed in terms of percent rooting, mean root number per rooted cutting, and length of the longest root per cutting, was regressed on level of pomace. When there were differences due to amendments, most species rooted better with perlite than with bark and peat, to a lesser degree, due in part to more favourable air-filled porosities with perlite (33% to 42%) than with bark (29% to 37%) or peat (24% to 35%). With boxwood, increasing level of pomace up to ≈60%, especially when mixed with perlite or peat, resulted in substantial increases in rooting percentage, root number and length. All three rooting parameters of winged spindle-tree decreased linearly with increasing level of pomace with perlite or bark. The effect of pomace level on other species varied between these extremes with little or no negative effect on rooting.

Propagation of Ulmus parvifolia ‘Emerald Prairie’ by Stem Cuttings

Abstract Stem cuttings of Ulmus parvifolia Jacq. ‘Emerald Prairie’ (‘Emerald Prairie’ lacebark elm), consisting of 7.5 to 10 cm (3 to 4 in) terminal shoot portions, were collected four times throughout the year from mature stock plants and treated with the potassium (K) salt of indole-3-butyric acid (K-IBA) ranging from 0 to 20,000 ppm (2.0%). Rooting percentages were affected greatly by K-IBA treatment and stock plant growth stage. Little to no rooting was observed without K-IBA application, whereas overall rooting for treated softwood, early semi-hardwood, late semi-hardwood, and hardwood, cuttings was 92, 86, 87, and 8%, respectively. Mean root number varied by growth stage and K-IBA concentration. Higher concentrations of K-IBA increased the number of roots on rooted cuttings except for hardwood cuttings. In general, rooting percentage and mean root number were highest at the softwood stage with 15,000 or 20,000 ppm (1.5 or 2.0%) K-IBA, resulting in 97% rooting and 15 or 22 roots per rooted cutting, respectively. However, leaf abscission was high on softwood cuttings. Semi-hardwood cuttings achieved similar rooting percentages and may exhibit better survival and growth due to greater leaf retention.

The effect of age and type of rootstock, method of scion placement and light intensity levels on the performance of <I>Uapaca kirkiana </I>(Muell. Arg) micrografts cultured <I>in vitro</I>

A study was done to investigate the effects of age and type of rootstock, method of scion placement and light intensity on successful micrografting in Uapaca kirkiana, a miombo woodland fruit tree. Experiments were conducted to determine the interaction between the effects of age and type of rootstock and method of scion placement; and age and type of rootstock and light intensity. In the first experiments, rootstocks at ages 2-, 3-, 4- and 5-months; type of rootstock: rooted and unrooted; and method of scion placement: cleft and side grafting were used. Treatments for the second experiment included rootstocks at ages 2-, 3- and 4-months; type of rootstocks: rooted and unrooted; and light intensity levels of 0, 45, 135 and 225 µMm-2s-1. Results indicate that cleft grafting gave higher percentages (49.3%) than side grafting (47.9%). The performance of the micrografts arising from rooted rootstocks was better compared with unrooted rootstocks. The mean number of roots per micrograft from rooted rootstocks was 2.3 as compared to 1.6 roots from unrooted rootstocks. The optimal level of success can be achieved when 3-month old rooted rootstocks are used for micrografting and the cultures are incubated under an illumination of 45 µMm-2s-1 with a possible graft take of at least 60%. UNISWA Jnl of Agric Vol 10 2001: pp22-29

The role of vegetative propagation in the domestication of Pausinystalia johimbe (K. Schum), a highly threatened medicinal species of West and Central Africa

Pausinystalia johimbe (K. Schum), a tree of the Central Africa humid lowlands, is exploited for its bark to supply both export and local medicinal plant markets. The gradual destruction of the forests in which Yohimbe grows coupled with unsustainable bark harvesting methods, has resulted in local scarcity of this tree species. The study examined the amenability of P. johimbe to vegetative propagation through the rooting of leafy stem cuttings using low-cost technology polythene propagators. Using single-node leafy cuttings, three experiments were investigated in Cameroon: (i) Three propagation media (sawdust and 50:50 mixture of sand and sawdust). Initially, rooting was best in the mixed medium, but subsequently, cuttings set in the sawdust rooted better than those in sand and the mixture of sand/sawdust. However, there was no significant ( P >0.05) treatment effect on rooting percentage or on the mean number of roots per cutting. (ii) Three types of auxin at 50 μg per cutting (IAA, indole-3-acetic acid; IBA, indole-3-butyric acid and NAA, 1-naphthalene acetic acid) dissolved in 10 μl of alcohol. The control treatment received 10 μl of alcohol only. Significant differences in rooting percentage occurred after 3–4 weeks between the auxin-treated cuttings and the control. Within the same period IBA-treated cuttings rooted better than those with NAA and IBA. (iii) Four leaf areas: 0, 50, 100 and 200 cm 2 . Leafy cuttings rooted better than leafless cuttings after 4–5 weeks, with 50 cm 2 leaf area being the best from week 6. Significantly higher cutting mortality ( P <0.05) occurred for leafless cuttings than for leafy cuttings. The present study clearly indicated that P. johimbe is amenable to vegetative propagation technique using juvenile single-node leafy cuttings.

The role of vegetative propagation in the domestication of Pausinystalia johimbe (K. Schum), a highly threatened medicinal species of West and Central Africa

Pausinystalia johimbe (K. Schum), a tree of the Central Africa humid lowlands, is exploited for its bark to supply both export and local medicinal plant markets. The gradual destruction of the forests in which Yohimbe grows coupled with unsustainable bark harvesting methods, has resulted in local scarcity of this tree species. The study examined the amenability of P. johimbe to vegetative propagation through the rooting of leafy stem cuttings using low-cost technology polythene propagators. Using single-node leafy cuttings, three experiments were investigated in Cameroon: (i) Three propagation media (sawdust and 50:50 mixture of sand and sawdust). Initially, rooting was best in the mixed medium, but subsequently, cuttings set in the sawdust rooted better than those in sand and the mixture of sand/sawdust. However, there was no significant ( P>0.05) treatment effect on rooting percentage or on the mean number of roots per cutting. (ii) Three types of auxin at 50 μg per cutting (IAA, indole-3-acetic acid; IBA, indole-3-butyric acid and NAA, 1-naphthalene acetic acid) dissolved in 10 μl of alcohol. The control treatment received 10 μl of alcohol only. Significant differences in rooting percentage occurred after 3–4 weeks between the auxin-treated cuttings and the control. Within the same period IBA-treated cuttings rooted better than those with NAA and IBA. (iii) Four leaf areas: 0, 50, 100 and 200 cm 2. Leafy cuttings rooted better than leafless cuttings after 4–5 weeks, with 50 cm 2 leaf area being the best from week 6. Significantly higher cutting mortality ( P<0.05) occurred for leafless cuttings than for leafy cuttings. The present study clearly indicated that P. johimbe is amenable to vegetative propagation technique using juvenile single-node leafy cuttings.

Influences of antibiotics on plantlet regeneration via organogenesis in loblolly pine (Pinus taeda L.)

Three antibiotics ampicillin, carbenicillin, and cefotaxime were evaluated for their effects on induction, growth, and differentiation of organogenic calli, as well as rooting of regenerated shoots of three loblolly pine (Pinus taeda L.) genotypes. Of the antibiotics administered, cefotaxime maximally increased the frequency of callus formation and growth rate of organogenic calli, carbenicillin maximally increased the frequency of shoot regeneration and the average number of adventitious shoots per piece of organogenic callus, ampicillin maximally decreased the rooting frequency of regenerated shoots and mean number of roots per regenerated shoot, in comparison with antibiotic-free media. Compared with the control, ampicillin minimally increased the frequency of callus formation, cefotaxime minimally increased the frequency of shoot regeneration, and carbenicillin minimally decreased the rooting frequency of regenerated shoots in three loblolly pine genotypes tested. All three antibiotics increased the frequencies of callus formation and shoot regeneration, and reduced the rooting frequency of regenerated shoots suggested that the establishment of an efficientAgrobacterium tumefaciens-mediated transformation protocol for stable integration of foreign genes into loblolly pine need to select a suitable antibiotic. This investigation could be useful for optimizing genetic transformation of conifers.

Foliar nutrition of in vitro-cultured Prosopis chilensis (Molina) Stuntz shoots

Foliar nutrition has been conceived as a possible means of overcoming the recalcitrance of Prosopis chilensis (Molina) Stuntz explants to standard in vitro culture. The foliar uptake of cations (K from 20 gl−1 KNO3 and Ca from 50 gl−1 CaCl2), anions (NO3 from 50 gl−1 KNO3 and PO4 from 50 gl−1 NaH2PO4), and glucose from a 100 mg l−1 solution studied. All of the nutrients examined were absorbed. The efficacy of foliar nutrition in prolonging the vigor of micropropagated P. chilensis shoot tips was compared with nutrients supplied as a liquid to the base of the stem (liquid) or as an agar-solidified medium (agar). A foliar-feeding apparatus was constructed that employed pressurization of the medium reservoir to drive the medium into the culture vessel with a passive return by a siphoning effect. The medium used was Murashige and Skoog with 30 gl−1 sucrose, 0.1 mgl−1 benzylaminopurine, and 1 mgl−1 indole-3-butyric acid. Over a 9-wk test period it was found that explants cultured by foliar nutrition performed significantly better than those grown on agar for shoot length, nodal production, and leaf retention; and better than liquid MS for node production. There was no significant difference among the three treatments in percentage survival, percentage rooting, or the mean number of roots.

ORGANOGÊNESE E TRANSFORMAÇÃO GENÉTICA DE MARACUJÁ AMARELO (Passiflora edulis f. flavicarpa DEG.) COM OS GENES CMe-ACO1 AS E nptII VIA Agrobacterium tumefaciens

O Brasil é o principal produtor mundial de maracujá – amarelo (Passiflora edulis f. flavicarpa Deg.). Seus frutos, de grande valor nutricional e farmacêutico são comercializados in natura e industrializados, garantindo o abastecimento do mercado interno e exportação. Contudo, seus frutos perdem grande quantidade de água durante o processo de maturação, conferindo à eles um aspecto de murcha em poucos dias, além de aumentar a fragilidade durante o transporte. Assim, o presente trabalho teve como principal objetivo, introduzir em tecidos desta espécie o gene que codifica para a enzima ACCO, em orientação antisense, via Agrobacterium tumefaciens. Esta enzima é responsável pela conversão do ácido 1-carboxílico -1 - aminociclopropano (ACC) em etileno, promovendo a maturação dos frutos. Como controle do processo de transformação, foi utilizado o gene nptII, que confere resistência ao antibiótico canamicina e que foi introduzido com sucesso nesta espécie em trabalhos anteriores. A transformação genética só é obtida com sucesso, se os explantes potencialmente transgênicos adquirirem aptidão para regenerar uma nova planta. Neste sentido, dois experimentos de organogênese foram realizados. Neles avaliou-se o efeito da idade fisiológica dos explantes (jovem e adulto); da posição de cultivo dos explantes (abaxial e adaxial) e o efeito da citocinina BAP: 1,0; 1,5 e 2,0 mg.L-1 na porcentagem de explantes com gemas, no número médio de gemas por explante, número médio de folhas por explante, comprimento médio das folhas, comprimento da haste principal e porcentagem de explantes que formaram calos. Os experimentos foram realizados sob delineamento experimental inteiramente casualizado, com quatro repetições de cada tratamento e dez explantes por parcela. A concentração 1,5 mg.L-1 de BAP promoveu os melhores resultados para todas as variáveis avaliadas, em ambas as posições de cultivo do explante e para tecidos jovens e adultos. Foi observada formação excessiva de calos na concentração de 2,0 mg.L-1 de BAP. Explantes foliares jovens, oriundos de sementes, regeneraram gemas adventícias em 50,22% dos casos após 30 dias de cultivo, em ambas as posições do explante no meio de cultura. Já os genótipos IAPAR 309, 156 x 123 e 352 (material adulto), apresentaram maior porcentagem de explantes regenerados quando estes foram cultivados na posição adaxial. O alongamento e enraizamento dos brotos foram obtidos em ambos os tratamentos: MS e MS/2 + 1 mg.L-1 de GA3. No entanto, o segundo tratamento resultou em maior comprimento de haste (3,73 cm), número médio de raízes por plântula (2,08) e comprimento de raízes (6,64 cm) após 60 dias de cultivo. Nos ensaios com Agrobacterium, apenas uma planta de seis regeneradas e enraizadas em meio seletivo apresentou o gene antisense da ACCO, com uma eficiência de transformação de 1,43%. Para o gene nptII esta eficiência foi de 4,3%. Estes resultados foram confirmados pela técnica de PCR. Uma análise colorimétrica de frutos comerciais foi realizada e permitiu a classificação destes frutos em três grupos: predominantemente verde, predominantemente colorido e totalmente colorido. A produção de etileno e atividade enzimática da ACCO foi avaliada, mostrando que o maracujá – amarelo é produtor intermediário de etileno e que a atividade enzimática da ACCO é limitada, necessitando de cofatores para sua atividade máxima.

Successful vegetative propagation techniques for the threatened African pencil cedar ( Juniperusprocera Hoechst. ex Endl.)

Rooting efficiencies of cuttings derived from three age class stock plants of African pencil cedar ( Juniperus procera Hoechst. ex Endl.), were studied using eight different concentrations of indolebutyric acid (IBA), viz. 0.00, 0.05, 0.10, 0.20, 0.40, 0.80, 1.60 and 3.20%. The number of cuttings used in anyone treatment ranged from 60 to 70. IBA applied at either 20 μg per cutting (for cuttings derived from 5-month-old stock plants) or at 40 μg per cutting (for cuttings derived from 10- and 15-month-old stock plants) resulted in significantly higher rooting responses compared to the control ( P<0.001). Whereas callusing in cuttings derived from the 5-month-old stock plants declined with increasing IBA level ( r=−0.78, P<0.05), rooting increased up to only 0.2% IBA. There were significant differences ( P<0.001) among the rooting responses of cuttings derived from 5- and 15-month-old stock plants, as well as among those derived from 10- and 15-month-old stock plants. The number of rooted cuttings and the corresponding root number declined rapidly when cuttings were treated with IBA beyond the 0.4% level. None of the cuttings derived from any of the age classes survived the lethal effects of IBA when this was applied at a concentration of 160 and 320 μg per cutting. By far the most significant effect of IBA was on the total root number. Mean root number increased by over three-fold in cuttings derived from all the three categories of stock plants when these were treated with 40 μg of IBA per cutting. The effectiveness of applied IBA in inducing rooting and in increasing the total root number increased with the age of stock plants from which cuttings were derived. Cuttings derived from 15-month-old stock plants needed higher IBA concentration, and the magnitude of the response (relative to the control, and in terms of rooting ability) was higher compared to those derived from 5-month-old stock plants. Interestingly, a significant number of cuttings derived from the more mature stock plants tended to produce roots without undergoing tissue dedifferentiation. Conversely, more than 95% of the control cuttings derived from 5-month-old seedlings produced calli, hence developing the majority of their roots after tissue differentiation had taken place. Growth of stecklings was proportional to the number of roots and (provided that growing conditions are optimal) planting size stecklings could be produced within about 10 months after transplanting rooted cuttings from the rooting medium to potted soils. With an overall rooting success of 60–80%, and with a reasonably good growth rate of stecklings, production of planting material from juvenile stock plants of J. procera through vegetative means, and through use of low-cost propagators, offers opportunities for a cheaper, practically sound and technically less demanding alternative means of propagation.

Shading and IBA Treatment Do Not Improve Rooting of Stem Cuttings of Quercus phillyraeoides ‘Emerald Sentinel’

Abstract Shoot tip cuttings of Quercus phillyraeoides A. Gray ‘Emerald Sentinel’ (‘Emerald Sentinel’ oak), in a transitional growth stage between softwood and semi-hardwood, were collected from containerized plants growing under uniform fertility on June 4, 1998. Cuttings were treated with talc formulations of indolebutyric acid (IBA), ranging from 0 to 8000 ppm (0.8%), and placed under intermittent mist with shade levels excluding 0%, 30%, 60% or 90% of full solar irradiance. After 14 weeks, percent rooting averaged 18% and was unaffected by either IBA concentration or shading regime. Similarly, both mean root number per rooted cutting and mean root length were unaffected by IBA concentration or shading. Roots per rooted cutting and mean root length averaged 2.6 and 41 mm (1.6 in), respectively. Results suggest that shading stem cuttings of ‘Emerald Sentinel’ during propagation does not affect rooting.

Rooting of Deciduous Woody Stem Cuttings in Peat- and Perlite-amended MSW Compost Media

Terminal stem cuttings of seven deciduous woody taxa [coralberry (Symphoricarpos × chenaultii Rehd. ‘Hancock’), snowberry (Symphoricarpos albus (L.) S.F. Blake), European cranberry bush (Viburnum opulus L.), lilac (Syringa velutina Kom.), purple osier (Salix purpurea L. ‘Nana’), purple-leaf sandcherry (Prunus × cistena N.E. Hansen), and winged spindle-tree (Euonymus alata (Thunb.) Siebold. ‘Compacta’)] were rooted under outdoor lath (50% shade) and mist in rooting media consisting of 0, 15, 30, 45, 60, and 75% by volume of MSW compost mixed with sphagnum peat or perlite. Rooting performance, expressed in terms of percent rooting, mean root number per rooted cutting, and length of the longest root per cutting, was regressed on level of compost. When there were differences due to amendments, most taxa rooted better with perlite than with peat due largely to more favourable water (36-50%) and air (16-26%) porosities with perlite than with peat (water, 60-60%; air, 12-15%). Cranberry bush, an exception, rooted better in the peat-amended compost. Increasing level of peat-amended MSW compost resulted in a large curvilinear decrease (adverse effect) in percent rooting of winged spindle-tree. Contrastingly, increasing level of both peat-and perlite-amended MSW resulted in moderate to substantial linear or curvilinear increases (beneficial effect) in root number and/or root length of coralberry and snowberry cuttings. MSW level had little or no effect on the rooting responses of other taxa.

584 The Effects of IBA Hormone Concentration, Cutting Type, and Media on Rooting of Local Hazelnut Cuttings

This work was conducted for the purpose of propagation of hazelnut cuttings, using hard-, semi-hard-, and softwood cuttings produced from 1-year-old suckers of local varieties of hazelnuts from the Alamout-Qazvin area of Iran. The research was carried out in a greenhouse with a mist system at the Faculty of Agriculture of Tarbiat Modarres University. This experiment was based on the complete randomized-block design with a factorial framework and resulted in two levels of 5% + 1% according to the Duncan test. The effect of rooting media (sand and pumice), cutting type (hard-, semi-hard-, and softwood), and use of a hormone with five concentrations (control, 1500, 3000, 4500, and 6000 ppm IBA) were investigated. The cuttings, being wounded and treated with hormones on certain beds, were kept in a greenhouse with a mist system. After 4 months, the number of rooted cuttings, mean number of roots per rooted cuttings, total length of roots, mean length of one root, average of dry weights, and average of young shoots were evaluated. The results indicate that the rooting medium and hormone are considerably effective for rooting of the cuttings and is considered as a significant facture. The general conclusion is that the most favorable result is reached with pumice and 4500 ppp IBA. The interaction between rooting medium and hormone on the rooting process was significant, and finally, it was found that there is not a significant relation between callusing and rooting in hazelnut. Also, the wounding is an effective factor for rooting of hazelnut cuttings.

ROOTING OF BRANCH CUTTING OF LAGERSTROEMIA SPECIOSA RETZ., EUCALYPTUS CAMALDULENSIS, DEHN. AND ERYTHRINA INDICA, LAM.

Rooting trials of branch cuttings of jarul (Lagerstroemia speciosa Retz.), eucalyptus(Eucalyptus camaldulensis Dehn.) and mandar (Erythrina indica Lam.) from 30,15 and 10 years old trees respectively were conducted treating them with Indole Butyric Acid (IBA) powder (0.4 or 0.8% IBA) and setting them under open mist. In Jarul, IBA had positive effect on rooting success and rooting time. Both root number and root length per cutting was also enhanced by IBA application. In the leafy cutting of eucalyptus, rooting success was significantly influenced by the IBA concentrations. The highest rooting percentage was found in cuttings treating with 0.8% IBA. For mean root number and root length, IBA did not show any positive effect. In mandar, IBA did not show any positive effect on rooting success, mean root length and root number.

Propagation of Thuja x ‘Green Giant’ by Stem Cuttings: Effects of Growth Stage, Type of Cutting, and IBA Treatment

Abstract Stem cuttings of Thuja L. x ‘Green Giant’ (‘Green Giant’ arborvitae), consisting of 22 cm (8.6 in) terminals (tips of first-order laterals) or 20 cm (7.8 in) laterals (side shoots removed from those portions of terminal cuttings inserted into the rooting medium), were collected on three dates associated with specific stock plant growth stages (softwood, semi-hardwood, and hardwood) and treated with indolebutyric acid (IBA) in 50% isopropanol ranging from 0 to 9000 ppm (0.9%). Regardless of cutting type or auxin treatment, cuttings rooted in high percentages at each growth stage. Overall rooting for softwood, semi-hardwood, and hardwood, cuttings was 85%, 86%, and 96%, respectively. Semi-hardwood cuttings were the only cuttings in which percent rooting was affected by IBA treatment or cutting type, with lateral cuttings rooting in higher percentages than terminal cuttings (92% vs. 79%, respectively), while IBA concentrations of 3000 (0.3%) or 6000 ppm (0.6%) proved optimal for both cutting types. Mean root number and mean root length varied by growth stage, cutting type, and IBA concentration. In general, rooting percentages and root length were optimized at the hardwood stage with either cutting type treated with 3000, 6000 or 9000 ppm (0.3%, 0.6% or 0.9%) IBA, resulting in &amp;gt;10 roots per cutting.

Asexual propagation of Juniperus procera from Ethiopia: a contribution to the conservation of African pencil cedar

The rooting responses of branch cuttings of Juniperus procera Hochst. ex Endl., obtained from young (Class I) and mature (Class II) source plants to four plant growth regulators (PGRs), namely, indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D) applied at various concentrations (10 −3–10 −9 M) were examined in sand culture. Assessments on rooting, as well as on root number and root length, of the cuttings were conducted 16 and 32 weeks after treatment. Histological origin of root primordia was examined microscopically. Establishment and performance of stecklings were assessed on sample rooted cuttings. Only 2% of the cuttings obtained from young (Class I) source plants rooted 16 weeks after treatment; and 24% of these cuttings rooted 32 weeks after treatment. Of the cuttings collected from mature (Class II) source plants, only a single cutting could root 32 weeks after treatment. The maximum attainable rooting percentage was 60, and was obtained from cuttings of Class I stock plants when these were treated with IAA at 10 −7 M. Cuttings treated with 10 −6 M IAA and the control resulted in a relatively higher root number (17±4.1 and 17±1.7). Those that were treated with 10 −3 M NAA yielded relatively longer roots (372.3±51.5 mm). Mean root number and length of the control were significantly greater than most of the PGR treatments ( p< 0.05). In this species, cells of callus tissue, cambium, cortex, as well as xylem cells, could give rise to root primordia. Stecklings with well developed root systems were easily established and grew well indicating the suitability of the species for propagating through vegetative means.

Comparative rooting of deciduous landscape shrub cuttings in media amended with paper mill biosolids from four different sources

Scarcity of landfills has resulted in increasing need for alternative disposal or reuse of industrial organic wastes such as paper mill sludge (biosolids). The objective of this study was to evaluate and compare the rooting response of stem cuttings from six species of deciduous landscape shrubs [coralberry (Symphoricarpos × chenaultii Rehd. 'Hancock'); flowering almond (Prunus triloba Lindl. 'Multiplex'); honeysuckle (Lonicera × xylosteoides Tausch. 'Clavey's Dwarf'); mock orange (Philadelphus × virginalis Rehd. 'Minnesota Snowflake'); purple-leaf sandcherry (Prunus × cistena N. E. Hansen); and viburnum (Viburnum dentatum L.)] under mist and 50% shade (outdoor lath) in flats filled with 100% perlite medium, or perlite mixed with 15, 30, 45 or 60% of fresh paper mill biosolids, by volume, of one of four sources (Atlantic, Domtar, Thorold, and QUNO). There was little or no adverse effect of the biosolids, despite wide variability in rooting response due to species, source and/or level of biosolids. Regression analyses indicated that, with few exceptions, the percent rooting, mean root number per rooted cutting, and length of longest root per cutting increased linearly or curvilinearly, or was unaffected, when regressed over level of biosolids. Optimum amounts of biosolids in the rooting medium ranged from 30 to 60% by volume. The electrical conductivities of the biosolids-amended media were acceptable (0.1–0.3 dS m−1) for rooting of woody cuttings and pore space characteristics were comparable to, or exceeded those of, perlite. Key words: Ornamentals, landscape plants, propagation, organic waste, paper mill sludge, waste recycling

In Vitro Micropropagation of Alfalfa (Medicago sativa L.) Cultivars

Shoot multiplication of the Alfalfa cultivars "Elçi" and "Mesa-Sirsa" was achieved from the shoot tips of in vitro germinated seedlings. Shoot tips were cultured in a basal medium supplemented with different concentrations of 6-benzylaminopurine (BAP) and a-naphthaleneacetic acid (NAA). The number of shoots obtained was higher in the medium containing 2 mg/l BAP and 0.2 mg/l NAA for "Elçi" and 1 mg/l BAP and 0.2 mg/l NAA for "Mesa-Sirsa". In both cultivars, the mean length of shoots was significantly higher on the MS medium supplemented with 2 mg/l BAP and 0.2 mg/l NAA. The percentage of roots reached up to 80-90 % with increasing IBA (indole butyric acid) concentrations in the culture medium. The mean number of roots per shoot was also influenced by IBA concentrations, but there were no treatment effects on the root length of either cultivar. However, the mean root length was higher in "Elçi" than in "Mesa-Sirsa". No change was observed in the number of somatic chromosome of the shoots developed in the culture.

Propagation of Quercus phillyreoides by Stem Cuttings

Abstract Stem cuttings of two clones (clones 1 and 2) of seedling origin of Quercus phillyreoides A. Gray (ubame oak) in the adult growth phase were taken on four dates that represented four growth stages (semi-hardwood, hardwood, softwood, and transitional growth between softwood and semi-hardwood). All cuttings were treated with selected concentrations and formulations of indolebutyric acid (IBA) and placed under intermittent mist for rooting. Greatest rooting for both clones was achieved with softwood cuttings with 97% and 56% rooting for clones 1 and 2, respectively, treated with 8000 ppm (0.8%) IBA in talc. Six weeks later when cuttings were in a softwood/semi-hardwood condition, rooting of clone 1 was still comparable to softwood cuttings whereas clone 2 rooted poorly. For both clones, rooting of semi-hardwood cuttings was poor, which was the same for hardwood cuttings of clone 2. Moderate rooting of 58% was noted for nontreated hardwood cuttings of clone 1. Auxin treatments generally increased root number. As mean root number increased mean root length decreased. Greater overwinter survival was observed for rooted softwood cuttings, which produced a flush of new growth following rooting in comparison to softwood/semi-hardwood cuttings that did not flush following rooting.

Light quality of thein vitrostage affects the subsequent rooting and field performance ofbetula pendula(Roth)

The influence of irradiance and light quality on in vitro cultures was studied at the rooting stage, and subsequently as it affected the field performance of birch (Betula pendula Roth.). Forty‐five μmol m−2 s−1 during the rooting stage reduced the rooting time compared with 30 μmol m−2 s−1. The light quality treatments of the cultures, from which the microcuttings were harvested, had a larger effect on the rooting than the treatments during the rooting stage. The fastest rooting was observed in microcuttings pre‐treated with blue light (6 days), and the slowest rooting after treatments with red light (12 days), which also, respectively, gave the highest (5.1) and lowest (3.5) mean number of roots per microcutting. The largest growth rate in the field was observed in plantlets harvested from cultures subjected to blue and cool white light.

Hot-Water Immersion of Chrysanthemum Cuttings, Hawaii, 1992

Abstract Phytotoxicity trials were conducted from 29 Oct through 4 Dec 1992. Chrysanthemum tip cuttings (2.5 inch) were immersed in 49°C water from 0 to 10 min at 1-min intervals. Each treatment time consisted of 24 cuttings except 0 and 5-min exposure times which consisted of 22 cuttings. Immediately following treatment, all cuttings including the control were cooled in a water bath at ambient temperature (26.1°C) for five minutes. Cuttings were subsequently basal treated with 0.1% indole-3- butyric acid rooting powder (IBA), planted in vermiculite in plastic trays, and kept under mist (13 s mist every 2.5 min) in a fiberglass greenhouse. Eleven days after treatment, data were taken on the percentage of cuttings with roots, mean length of the three longest roots, mean number of roots and mean dry weight of the root mass from 12 cuttings (4 reps of 3 cuttings per rep) selected at random from each time interval. The remaining cuttings were transplanted in 3 inch plastic pots containing a 3:1:1 mixture of peat, vermiculite and perlite; and placed randomly on a bench in a fiberglass greenhouse. Data on plant height, and percent survival were taken 36 days after treatment.