Morphological and oil content variations amongst Damask rose (Rosa damascena Mill.) landraces from different regions of Iran

Forty landraces of Damask rose were collected from 28 provinces (13 origin sites) in Iran and evaluated to determine the diversity among them. The investigated characters were: flower weight, flower diameter, peduncle length, number of petals, number of stamens and oil content. Pearson's coefficients showed that number of petals was positively correlated with flower weight (r = 0.642) and number of stamens (r = 0.630), while its correlation with peduncle length was negative (r = −0.53). A negative correlation was obtained between oil content and number of stamens (r = −0.60) which is useful for indirect selection of landraces with low number of stamens and therefore high amount of oil content. Cluster analysis based on five botanical characters and oil content separated the origin site 12, which included Guilan, Mazandaran and Golestan provinces with a specific climate condition of temperate humid, from other origin sites. This distinctiveness was already confirmed by the bi-plot of the principal components. The distribution of Damask rose landraces provided useful information for the future collection and for the genetic resource management in these origin sites.     

Cold storage of oil rose (Rosa damascena Mill.) flowers

Oil rose flowers were stored at 0 °C in four different packaging materials [plastic box + stretch film (PB + SF), Xtend^®, Smartbag^® and polyethylene (PE)] for 60 days. During storage, weight loss, O₂ and CO₂ concentrations in the packages, petal color and sensorial attributes were investigated besides essential oil content and composition. Storage duration and packages had significant (p < 0.01) effects on weight loss. At the end of storage, the lowest weight loss was in PE package (1.696%) whereas the highest weight loss was in Xtend^® (10.081%). The essential oil content was significantly (p < 0.01) affected by storage duration and packages. In addition, the essential oil contents obtained from all packages for a storage period of 10 days and the essential oil contents obtained from unstored (control) petals were included in the same group. At the end of storage, the essential oil contents decreased by 91.3, 57.7, 80.0 and 64.3% in PB + SF, Xtend^®, Smartbag^® and PE packages, respectively as compared to control. In addition, storage duration and package types significantly (p < 0.01) affected petal color, O₂ and CO₂ concentrations in the packages and sensorial scores. The concentration of citronellol, a main component of rose oil, increased in all packages during storage of 10 days in comparison to the control group while it varied in other storage durations and package types. However, nerol and geraniol were lower than the control group during storage while concentrations of nonadecane, heneicosane and eicosane were higher. In conclusion, loss of oil yield and quality, due to various reasons and particularly due to fermentation in oil rose from the harvest of petals to their distillation, can be minimized with storage of petals in all package types for up to 10 days.     

Flower yield performance and stability of various Rosa damascena Mill. landraces under different ecological conditions

The flower yield stability of Damask rose as an important medicinal and aromatic plant at different environments has not been well documented. In order to evaluate flower yield and stability, 35 landraces of Damask rose were studied at 8 locations in Iran during 2007–2008. Analysis of variance revealed significant differences (p ≤ 0.01) among landraces (G), environments (E), locations (L) and for landrace × environment (GE) and landrace × location (GL) interactions. Both GE and GL interactions were mainly crossover, a large portion of which was accounted for by non-linear (unpredictable) component. The landraces of IS9, YZ2, WA1, IS7 and IS1 with 3120.63, 2941.63, 2894.62, 2769.15 and 2716.92 kg/ha respectively produced the highest flower yield among studied landraces. Kerman with average flower yield of 3635.46 kg/ha produced the highest yield among studied locations. According to the results, most of landraces that originated from temperate, warm temperate and arid regions produced higher flower yield than those from cool, cool temperate, semi-arid and humid regions. The landraces of YZ2, IS5, IS8, IS4, KZ1, AR1_, IS3 and BA1 were stable and YZ2, IS5, IS8, IS4, KZ1, AR1 IS6, IS3, BA1, IS10 and YZ1 were adaptable landraces for flower yield according to Eberhart and Russell (1966) model. The presence of some high flower yield and stable landraces such as YZ2 and IS5 suggests that a genotype can demonstrate high flower yield and stability for yield simultaneously. Thus, simultaneous selection for flower yield and stability using nonparametric methods could be possible. In addition, taking into consideration flower yield and stability potential, the landraces of YZ2, IS5, IS8, IS4 and KZ1 as general stable, adaptable, and high flower yield are recommended. Furthermore, the landraces of IS9 and WA1 as high flower yield and specific adaptable landraces can be recommended for temperate and arid areas and the landraces of IS7 and IS1 for semitemperate and cool areas.     

In vitro proliferation from axillary buds and ex vitro protocol for effective propagation of Syringa × hyacinthiflora ‘Luo Lan Zi’

As a precondition for lilac mass propagation, the optimal shoot-multiplication medium for Syringa × hyacinthiflora ‘Luo Lan Zi’ was ascertained mainly based on clustered microshoot inducement and large leaf area establishment in 6-benzyladenine (BAP) (1.00 mg L⁻¹) and zeatin (Z) (0.10 mg L⁻¹) combination. Medium supplied with lower level of BAP (0.50 mg L⁻¹) and auxin (IAA) (0.25 mg L⁻¹) was not suitable for lilac shoot proliferation, but it could be competent for long-term preservation of the un-rooted shoots so that subsequent proliferation culture could be carried out at anytime. In addition, excess height growth which resulted in low transplanting survival rate was effectively controlled by decrease in node number when paclobutrazol (PBZ) was applied in rooting medium at a concentration of 1.00 mg L⁻¹ after taking into account the effects on shoot height, rooting, persistent leaf area and PBZ carry-over. An important overwintering treatment was to use a plastic chamber covering for plants in the greenhouse prior to field planting to ensure adequate biomass of stem and underground parts not only in the current growing season but also in the subsequent years.     

Agrobacterium × plant factors influencing transformation of ‘Joseph's coat’ (Amaranthus tricolor L.)

A protocol is developed for Agrobacterium-mediated genetic transformation of Amaranthus tricolor via explant co-cultivation with Agrobacterium rhizogenes. Bacteria-plant specific factors which influenced transformation were optimized. Of the two Agrobacterium strains employed, LBA9402 was more infectious compared to A4. Bacterial suspensions grown overnight with 100 μM acetosyringone and experiencing O.D.₆₆₀ = 0.6 followed by dilution to a density of 10⁹ cells ml⁻¹ were the most effective. Explants from garden-grown plants were more responsive than those from in vitro cultures; stem internodes being better than leaves. Immersion of the pre-pricked explants in bacterial suspension resulted in a markedly higher transformation frequency compared to the direct injection method. The infection of internode explants with the LBA9402 strain followed by co-cultivation on growth regulator-free MS medium (MS0) for 5 days resulted in emergence of hairy roots up to a maximum frequency of 97.22%. Roots were individually cultured in MS0, but fortified with bactericidal antibiotic (500 μg ml⁻¹ cefotaxime). Rhizoclones showing prolific growth were renewed through successive subcultures in MS0. Opine gene expression was revealed by positive agropine and mannopine synthesis in all selected transformed rhizoclones. Shoot regeneration from root clones, capable of auxin-independent growth and opine proficiency, was stimulated in MS augmented with 2.0 mg l⁻¹ zeatin. pRi TL–DNA rolB and pRi TR–DNA man2 ORF were detected in leaf tissues of regenerated plants from selected hairy root clones through PCR amplification. The implication of such findings is discussed on the possibility of conferring protection to crop amaranths against biotic stress challenges, particularly due to insects, viruses or fungal pathogens.     

Parental chromosome differentiation in citrangequat [Fortunella sp. × (Citrus sinensis × Poncirus trifoliata)] using CMA banding patterns

The efficiency of chromomycin A₃ (CMA) staining was examined for parental chromosome differentiation in citrange [Citrus sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.] and citrangequat (Fortunella sp. × citrange). All of the accessions analyzed had the same chromosome number of 2n = 18. CMA staining revealed six characteristic banding patterns on the basis of the number and position of CMA positive bands (CMA⁺) as follows; A: two terminal and one proximal band, B: one terminal and one proximal band, C: two terminal bands, D: one terminal band, E: no band, and F: one proximal band. Chromosome CMA banding patterns of the accessions were 1A + 1B + 2C + 13D + 1F in Fortunella margarita, 2B + 2C + 7D + 7E in ‘Fukuhara’ orange, 2B + 10D + 6E in Poncirus trifoliata, 1B + 1C + 10D + 6E in citrange and 1A + 1C + 11D + 4E + 1F in citrangequat. The results of this study confirmed the intergeneric and tri-generic hybridity of citrange and citrangequat, respectively.     

Auxin-dependent development and habituation of highbush blueberry (Vaccinium × covilleanum But. et Pl.) ‘Herbert’ in vitro shoot cultures

The influence of IAA (1.0 mg dm⁻³), and IBA (1.16 mg dm⁻³), on the development of highbush blueberry (Vaccinium × covilleanum But. et Pl.) ‘Herbert’ in vitro shoot cultures was examined. Depending on the kind of auxin and 2iP concentration in vitro cultures consisted of various number of axillary (AX) and adventitious (AD) shoots. Three different categories of AD shoots were found: leaf shoots (AD-L), node-adjoin shoots (AD-P), and base-adjoin shoots (AD-M, madshoots). The AX shoots were the least habituated (towards auxins, cytokinins and vitamins) whereas the AD-M shoots (madshoots) the most. In comparison to IAA, IBA caused dying or callusing higher number of initial explants. However, IBA generally suppressed development of AD shoots, especially madshoots whereas slightly weakened multiplication of AX shoots. IBA significantly enhanced elongation of AX shoots also. Axillary shoots obtained on IBA-media had relative long internodes and rigid, well-developed leaves. The adventitious shoots, especially base-adjoin (AD-M) ones, were easily distinguishable as were more thin and fragile, more or less vitrified, and had short internodes and smaller, sometimes unfolded leaves. Development of blueberry in vitro cultures on auxin-free and IAA-supplemented media was similar. AX shoots grown on such media resembled AD shoots. 2iP applied in higher doses along with IAA promoted much proliferation of AD than AX shoots. In contrast, 2iP applied in higher doses together with IBA stimulated significantly only growth of AX shoots whereas in general, development of adventitious shoots was not affected. Micropropagation carried out through routine method based on subculturing of shoot explants or shoot clumps on the medium supplemented with IAA (4 mg dm⁻³) and 2iP (10–15 mg dm⁻³) as well as stimulation of shoot elongation on the blank medium causes in fact the propagation of highbush blueberry through highly habituated adventitious madshoots. Replacement of IAA by IBA facilitates micropropagation of highbush blueberry cv. Herbert through axillary shoots.     

Effect of plant growth temperature on membrane lipids in strawberry (Fragaria × ananassa Duch.)

Changes in membrane lipid composition are important in the acclimation of plants. The influence of four day/night growing temperature combinations (18/12, 25/12, 25/22, and 30/22 °C) on membrane lipids of ‘Earliglow’ and ‘Kent’ strawberry (Fragaria × ananassa Duch.) were studied. The monogalactosyl diglyceride (MGDG) and digalactosyl diglyceride (DGDG) were the major galactolipids in the strawberry leaves. ‘Earliglow’ contained a higher amount of galactolipids in the leaves than ‘Kent’. The major phospholipids in the strawberry leaves, roots, and fruit were phosphatidylcholine (PC), phosphatidylinositol (PI), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE). PC and PE were the two predominant phospholipids in the strawberry. The leaves and fruit of ‘Earliglow’ contained higher amounts of phospholipids compared to those of ‘Kent’, whereas ‘Kent’ strawberry roots had higher phospholipids. Palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2), and α-linolenic (C18:3) acids were major fatty acids in galacto- and phospholipids of the ‘Earliglow’ and ‘Kent’ strawberry. PC is very rich in linolenic acid in leaves compared to the fruit and root tissues. PC had the highest ratio of unsaturated to saturated fatty acids among all phospholipids. There was a significant increase in the content of galactolipids (MGDG, DGDG) and phospholipids (PC, PI, PG and PE) and unsaturation of their fatty acids in the cool day/night growth temperature. Increasing day/night growth temperatures decreased MGDG/DGDG ratios. The shifts in saturation and composition of fatty acids observed with strawberry may be an adaptation response of plants to the temperature changes.     

Physiological and biochemical studies during flower development in two rose species

The present investigation was aimed to study the changes in various physio-chemical attributes in petals of two different rose species, Rosa damascena Mill and Rosa bourboniana Desport differing in flowering behaviour from small bud (stage 1) till full bloom (stage 8). In both rose species fresh weight, dry weight and moisture content were maximum during full bloom. Electrical conductivity of the petal diffusates reached maximum at full bloom with significantly higher values in R. damascena. In both the species, starch content declined as the flower reached its full bloom stage with maximum reducing sugar content during this period. With progressive increase in petal growth, total protein and RNA declined. The results showed that in both the species peroxidase (POX) and catalase (CAT) activity were lower during full bloom with high activity of invertase and lipoxygenase (LOX) at this period. The present study indicates that lipid peroxidation induced membrane permeability could partly be the result of higher lipoxygenase activity during full bloom. The possible significance of these findings is discussed in relation to flower development in the two diverse rose species.     

Aneuploid strawberry (2n = 8x + 2 = 58) was developed from homozygous unreduced gamete (8x) produced by second division restitution in pollen

Unreduced gamete formation is significant in the evolutionary development of complex polyploidy series found in wild strawberry, genus Fragaria (Rosaceae). Also, it is important for genetics and breeding in strawberry plants to elucidate the mechanism of unreduced gamete formation. The objective of this study was to search for ploidy anomalies resulting from artificial diploid × octoploid crosses, and examine the mechanism through which these unreduced gametes were produced. Five everbearing cultivars of Fragaria vesca L. diploid (2n = 2x = 14) were crossed with pollen from six June-bearing cultivars of Fragaria × ananassa Duch., octoploid (2n = 8x = 56). A total of 3000 mature seeds, 100 from each of the 30 parental combinations were sown at 23 °C/20 °C (day/night) under artificial lighting with a 16 h day. The seedlings were transplanted to pots and grown in a greenhouse. Reproductive and morphological observations, flow cytometry analyses, chromosome counts and DNA analyses using CAPS markers were performed to identify the genetic background of the offspring. Most of the seed (79%) did not germinate or died soon after germination. Of the seedlings produced, 7% seemed to be pure F. vesca based on morphological characteristics, flow cytometry analyses and chromosome counts; 14% were pentaploids (2n = 5x = 35), 0.1% were hexaploids (2n = 6x = 42), and 0.03% (one individual) was aneuploid (2n = 8x + 2 = 58). Electrophoresis banding patterns obtained by CAPS marker analysis were heterozygotic in the 8x pollen parent but homozygotic in the aneuploid progeny. Judging from the chromosome counts and the CAPS marker analysis, the aneuploid was the result of a homozygous unreduced pollen grain (8x) crossed with an incomplete chromosome compliment from the egg. Because of the homozygosity, the unreduced male gamete must have been derived from second division restitution (SDR) in the octoploid pollen parent.     

Changes in morphological phenotypes and essential oil components in lavandin (Lavandula × intermedia Emeric ex Loisel.) transformed with wild-type strains of Agrobacterium rhizogenes

Hairy roots were induced from leaf-derived calli of lavandin (Lavandula × intermedia Emeric ex Loisel.) by infection with wild-type strains of Agrobacterium rhizogenes, A-5 (MAFF 02-10265) and A-13 (MAFF 02-10266). A-5-inoculated calli formed hairy roots more efficiently than A-13 ones. The transgenic shoots could be obtained from hairy root segments mediated by each Agrobacterium strain. However, different plant growth regulators were required for efficient adventitious shoot formation in each strain. In A-5, the most efficient adventitious shoot formation rate of 23.8% was observed in a medium with 4.4 × 10⁻⁶ M of 6-benzylaminopurine. On the other hand, a significantly higher rate of 13.2% was detected in a medium with 4.0 × 10⁻⁷ M of N-(2-chloro-4-pyridyl)-N′-phenylurea in A-13. Most of the regenerated plants showed dwarfism with closed internodes and extensive lateral branching, which were typical characteristics of ‘hairy root syndrome’. On the other hand, only nine of the 45 regenerated plants formed flower buds in early June, a delay of about one month compared with nontransgenic regenerated plants. The floral stalks and spikes of these plants were very short, resulting in a compacted form. Many regenerants showed a significantly lower productivity of essential oil than nontransgenic regenerants. Moreover, the relative percentage of the linalyl-cation-derived compounds, linalool and linalyl acetate, decreased in most of the regenerated plants. Compact plants with the ability of flower bud formation are assumed to be valuable not only for lavandin breeding, but also for clarifying the interaction between rol genes expression and essential oil production.     

Interaction of short day and timing of nitrogen fertilization on growth and flowering of ‘Korona’ strawberry (Fragaria × ananassa Duch.)

The effects of timing of nitrogen (N) fertilization relative to the beginning of a 4-week floral-inducing short-day (SD) period have been studied in ‘Korona’ strawberry plants under controlled environment conditions. Groups of low fertility plants were fertilized with 100 ml of calcium nitrate solution for 3 days a week for a period of 3 weeks starting at various times before and at the beginning of the SD period, as well as at different times during the SD period. All plants, including SD and long day (LD) control plants, received a weekly fertilization with a low concentration complete fertilizer solution throughout the experiment. Leaf area, fresh and dry matter increments of leaves, crowns and roots, as well as leaf chlorophyll concentration (SPAD values) were monitored during the experimental period. A general enhancement of growth took place at all times of N fertilization. This was paralleled by an increase in leaf chlorophyll concentration, indicating that the control plants were in a mild state of N deficiency. When N fertilization was started 2 weeks before beginning of the SD period, flowering was delayed by 7 days, and this was gradually changed to an advancement of 8 days when the same treatment was started 3 weeks after the first SD. The amount of flowering was generally increased by N fertilization although the effect varied greatly with the time of N application. The greatest flowering enhancement occurred when N fertilization started 1 week after the first SD when the number of flowering crowns and the number of inflorescences per plant were more than doubled compared with the SD control, while fertilization 2 weeks before SD had no significant effect on these parameters. Importantly, the total number of crowns per plant was not affected by N fertilization at any time, indicating that enhancement of flowering was not due to an increase in potential inflorescence sites. No flowering took place in the control plants in LD. Possible physiological mechanisms involved and practical applications of the findings are discussed.     

Dormancy and germination in Rosa multibracteata Hemsl. & E. H. Wilson

Most of the achenes produced by Rosa multibracteata Hemsl. & E. H Wilson are dormant on maturity and require pretreatment to stimulate germination. To investigate the mechanism of dormancy and to develop effective methods of improving germination, roles of the pericarp, testa, and embryo of R. multibracteata in regulating dormancy were studied by investigating the effect of different pretreatments on germination. The effects of temperature and water stress were also tested with achenes treated by warm plus cold stratification. In freshly harvested achenes, pericarps are permeable and the embryo fully developed, which eliminates the possibility of physical, morphological, or morphophysiological dormancy. Germination percentage remained low (<5%) despite softening the pericarp or even removing it fully. However, fully removing the testa improved germination significantly (39%), indicating the possible presence of germination inhibitors in the testa. Dry storage, scarification with sulphuric acid (H₂SO₄), and warm stratification proved ineffective by themselves but when combined with cold stratification, improved germination and shortened the cold stratification period needed to break dormancy. Dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks resulted in maximum germination (72–79%) among all the treatments. In achenes scarified with H₂SO₄, germination increased with an increase in the duration of cold stratification. Neither gibberellic acid (GA₃) nor ‘smoke water’ (water through which smoke had been bubbled for 2 h) had any positive effect on germination even on seeds that had been mechanically scarified or stratified. Both high temperature and water stress lowered germination in achenes treated with warm plus cold stratification. Our results suggest that R. multibracteata achenes have an intermediate physiological dormancy, and that dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks is the best method for propagating R. multibracteata from seed.     

Fruit nutrient content and lipoxygenase activity in relation to the production of malformed and button berries in strawberry (Fragaria × ananassa Duch.)

Fruit nutrient content and lipoxygenase (LOX) activity were determined in strawberry fruit to establish a relationship, if it exists, between nutrients, and LOX activity with the fruit malformation and nubbins or button berry disorders. Nearly 17% fruit were affected by malformation and 10% by nubbins in open-field-grown strawberries. ‘Etna’ produced higher proportion of malformed (22.7%) as well as button berries (16.9%) and ‘Sweet Charlie’ the lowest (8.9% and 3.3%, respectively). Dry matter content (%) was lower in malformed (5.2%) and button berries (3.23%) than normal berries (7.41%). The concentration of P and Mg did not differ significantly, but that of N and K was notably higher and of Ca and B was lower in malformed and button berries than normal berries. Consequently, the N/Ca and K/Ca ratios were higher in malformed and button berries. LOX activity was significantly higher in malformed as well as button berries than normal berries, with significant differences among cultivars. The correlations between N, K and malformed and button berries were positive and between Ca and B, and malformed and button berries were negative. Similarly, the correlation between LOX activity and malformed, and button berries were also positive, indicating that excess of N and K, and deficiency of Ca and B are related to the production of malformed and buttons or nubbins in strawberry.     

Clonal propagation of Rosa clinophylla Thory. through axillary bud culture

A protocol for clonal propagation of Rosa clinophylla, a rare and endangered species but very important for breeding purposes had been standardized through in vitro axillary bud culture. Although cytokinins alone were able to induce shoot buds, but their proper growth and number could be increased only when they were used in combination with GA₃. However, there was shoot tip necrosis and leaf fall in the proliferated shoots. AgNO₃ at 58.85 μM proved effective to avoid shoot necrosis and yellowing of leaves. Activated charcoal (AC) at 250 mg l⁻¹ was found necessary at all the stages of shoot multiplication as well as rooting. Ninety percent rooting could be achieved in 1/2 MS medium supplemented with 4.92 μM IBA and 250 mg l⁻¹ AC. Rooted plantlets were hardened and transferred to the field successfully with 80% survival rate.     

Application of treated wastewater for cultivation of roses (Rosa hybrida) in soil-less culture

No information is available today concerning the effect of irrigation with secondary treated sewage water on growth, production or quality of roses or other cut flowers. In the present study we investigated the effect of irrigation with treated sewage water on roses cultivated in two soil-less medium, perlite, an inert mineral medium and Choir (coconut fibers), an organic medium of high ion absorption capacity. During 12 months of exposure to the treated water, the visible appearance of the plants, their growth, the quantity and size of the flowering stems and their postharvest performance were not affected by the irrigation treatments. Contents of macroelements in the leaf tissues were unaffected by the irrigation with the secondary treated sewage water. At the same time, Cl contents increased 47% in perlite and 73% in Choir grown plants reaching levels characteristic of exposure to moderate salinity. Mn, Cu and B contents increased as well under cultivation in both perlite and Choir under irrigation with treated sewage water. On the other hand, contents of Fe, Zn, Mo and Al, were similar in all treatments. In all treatments contents of all the examined micro and macroelements were within the range accepted for proper plant function.     

Hybrids sugary × sugary enhancer of sweet corn: A valuable option for cool environments

Sugary (Se1Se1) sweet corn hybrids do not have a high quality for human consumption according to the preferences of today's consumers, although they have a good stand establishment in cool environments. On the contrary, sugary enhancer (se1se1) hybrids have a high table quality, but a poor stand establishment in areas with a cool growing season. Sugary × sugary enhancer (Se1se1) sweet corn genotypes could be a valuable alternative for cool environments, but no information is available about the performance of sugary × sugary enhancer hybrids under such conditions. The objective of this paper is to evaluate the potential of sugary × sugary enhancer sweet corn genotypes in cool environments in comparison with sugary and sugary enhancer genotypes. Eight sugary lines and eight sugary enhancer lines were used as the parental lines of 15 sugary, 12 sugary enhancer, and 57 sugary × sugary enhancer hybrids that were evaluated in three different cool environments. The results of this work show that sweet corn cultivars with the Se1se1 genotype are an appropriate alternative for cool areas because they have better plant and ear types and a better eating quality than the Se1Se1 genotypes, and better emergence, early vigor, and shorter flowering time than se1se1 genotypes.     

6-Benzylamino purine stimulates in vitro shoot organogenesis in Eucalyptus erythronema, E. stricklandii and their interspecific hybrids

In vitro bud and shoot organogenesis was investigated for the ornamental plants Eucalyptus erythronema var. erythronema, E. stricklandii and their interspecific hybrids cv. ‘Urrbrae Gem’ and ‘Hybrid 2.5’ by using 0.0, 0.1, 0.25, 0.5 or 1.0 μM BAP on apex and leaf explants. Callus developed on all explants and increased with all concentrations of BAP without significant differences between BAP concentrations. Buds formed on apex and leaf explants of E. erythronema and E. cv. ‘Urrbrae Gem’ especially with 1.0 μM BAP, but these buds rarely developed into shoots. Bud clusters formed on E. erythronema and E. cv. ‘Urrbrae Gem’ apex and leaf explants whereas E. stricklandii and ‘Hybrid 2.5’ produced fewer, individual buds on the explant. Shoots regenerated from apex explants of all genotypes with all levels of BAP, whereas few shoots of any genotype regenerated from leaf explants regardless of the number of buds formed. Shoots from apex explants could be multiplied successfully. Light microscopy showed meristems developed within the callus, and at the callus and bud surfaces. However, few shoots developed considering the level of bud and meristem formation. This report is the first for successful shoot organogenesis and multiplication in an ornamental eucalypt.