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Lisianthus (Eustoma grandiflorum), a leading plant in the cut flower industry, is scentless. Here we show that lisianthus flowers have potential to produce several fragrant benzenoid-phenylpropanoids when substrate availability is not limited. To enable hyperaccumulation of substrates for the production of volatile benzenoid-phenylpropanoids, lisianthus commercial hybrid "Excalibur Pink" was transformed via floral dipping with a feedback-insensitive Escherichia coli DAHP synthase (AroG*) and Clarkia breweri benzyl alcohol acetyltransferase (BEAT), under constitutive promoters. The T1 progeny of "Excalibur Pink" plants segregated into four visual phenotypes, with pink or white colored petals and multiple or single petal layers. Interestingly, transformation with AroG* and BEAT caused no significant effect in the pigment composition among phenotypes, but did increase the levels of down-stream fragrant volatile benzenoids. All the transgenic lines exclusively accumulated methyl benzoate, a fragrant benzenoid, either in their petals or leaves. Furthermore, feeding with benzyl alcohol resulted in the accumulation of two novel benzenoids, benzyl acetate (the product of BEAT) and benzoate, as well as a dramatic increase in the concentrations of additional benzenoid-phenylpropanoid volatiles. Presumably, the degree of benzaldehyde overproduction after benzyl alcohol feeding in both leaves and flowers revealed their reverse conversion in lisianthus plants. These findings demonstrate the concealed capability of lisianthus plants to produce a wide array of fragrant benzenoid-phenylpropanoids, given high substrate concentrations, which could in turn open opportunities for future scent engineering.

Axillary meristems are the regenerating insurance of most plant species. They are initiated while the shoot apical meristem (SAM) produces leaves and usually remain inactive until a specific physiological change occurs. This common growth regulation is named “apical dominance”. In bulbous plants, axillary meristems initiate storage organs, which usually contain their own apical meristem. In Lilium longiflorum, an ornamental geophyte, the axillary meristems produce the bulbs of the following season. Large bulbs must get cold in order to flower, while small ones can flower without cold exposure under long-day conditions. Our aim was to clarify the foundation of the different flowering pathways regulated by bulb size, in view of the apical dominance mechanism, and identify its horticultural consequences. We monitored the development of L. longiflorum's bulbs produced from axillary meristems under an array of environmental and physiological alterations, including natural conditions and agrotechniques. The growth rate of L. longiflorum bulbs was highly affected by the developmental stage of the SAM, as well as by SAM decapitation and auxin application. Leaf biomass contributed as well to the final bulb size. Cold exposure quantitatively hastened flowering time and induced bud abortion. Bulb size and floral induction pathway (cold exposure or long-day conditions) affected flowering phenotype of the plants. We suggest a model by which apical dominance plays a major role in the reproductive strategy of L. longiflorum by regulating its prospective flowering pathways: either vernalization or photoperiod. This new concept enlightens the benefits of apical dominance for the plant growth-cycle under changing environments and disturbed habitats. Based on these results, we propose a novel horticultural protocol for lily forcing, taking into account the bulb size and the flowering pathway.

At the reproductive stage, lily plants bear two morphological types of mature leaves, one at the lower and one at the upper part of the stem. At the vegetative stage, all the leaves are similar to each other and to the reproductive plant's lower leaves. This heterophylly has not yet been explored. In this study, we show that it is not a result of the plant's age but rather an outcome of floral induction. The induction appears as an on-going process, during which the meristem still produces leaves but progressively becomes committed to reproduction. This intermediate period lasts until the ultimate switch to flower primordia occurs. The leaves produced during floral induction, termed here as "inductive," appear at the upper part of the stem. Besides their typical higher stomata density, these leaves have a poly-layered palisade mesophyll, whose cells exhibit a unique morphology and contain more chlorophyll than leaves of vegetative plants. These leaves display higher carbon assimilation, soluble sugar production, and chloroplast-lipid accumulation. Accordingly, genes associated with stomata, chloroplast, and photosynthesis are upregulated in these leaves. Our results were obtained when floral induction was achieved either by vernalization or photoperiod signals, ruling out a mere environmental effect. We suggest that lily plants prepare themselves for the high-energy-demanding bloom by producing leaves with enhanced photosynthetic capacity, leading to an increase in soluble sugars. These novel findings introduce an adjacent affinity between photosynthesis and flowering and provide a nondestructive tool for identifying the plant's developmental stage-vegetative or reproductive.

Lilium candidum L., known as Madonna, meadow, or white lily, is a bulbous plant from the Liliaceae family, originating in the Middle East. L. candidum has been abundantly used in folk medicine since ancient times to relieve a variety of ailments, including age-related diseases, burns, ulcers, and coughs. The aim of this article is to investigate the anti-inflammatory and anti-diabetic activities of L. candidum extracts and its active phytochemicals. Some active volatile phytochemicals were identified using gas chromatography&ndash, mass spectrometry (GC-MS) analysis. Significant (p &lt, 0.001) anti-diabetic properties of the extracts kaempferol, linalool, citronellal, and humulene were demonstrated by an elevation in glucose uptake by adipocytes. The significant (p &lt, 0.01) effect of the plant extracts kaempferol, citronellal, and humulene on the secretion of pro-inflammatory cytokines interleukin 6 (IL-6) and interleukin 8 (IL-8) was demonstrated using enzyme-linked immunosorbent assay. Altogether, L. candidum and its rich collection of phytochemicals hold promising medicinal potential, and further investigations of its therapeutic prospects are encouraged.

A bulb is a whole plant condensed into an underground organ. A geophyte's bulb comprises both food reserves and important developmental history that may affect its whole growth. In Easter lily (Lilium longiflorum), bulb size is associated with the plant's flowering pathway - vernalization or photoperiod - and also affects sprouting, flower quality and abortion rate. The aim of this study was to investigate the reasons for the major physiological differences between large and small bulbs. Lily bulbs start their development from secondary meristems along the stem, with large bulbs being heavier and bear more scales than small ones. Peeling the outer scales of a large bulb converts its physiological responses into those of a small bulb, implying that the physiological discrepancies in plants developing from large or small bulbs are mediated by factors inherent to the bulb. We therefore performed broad analyses of the metabolite composition in the scales of bulbs subjected to temperature regimes affecting further plant development. We found a striking association between the level of glycerol, a primary metabolite mostly synthesized in the outer scales, and a delay in sprouting and flowering time, and reduction in abortion rate. Exogenous glycerol application to the bulbs before planting corroborated these results. Moreover, transcriptome analyses showed that flowering-promoting gene expression was downregulated in the bulb after glycerol treatment, while potential flowering inhibitor as well as a dormancy-related gene expressions were upregulated. Based on these studies, we postulate that glycerol is a major factor influencing both vegetative and reproductive development in lily.

The adaptation of the Agrobacterium-mediated floral-dipping technique is limited, to date, to a small number of plants. In this paper, we present the efficient transformation of one of the leading plants in the cut flower industry, lisianthus (Eustoma grandiflorum). This method is approximately 18 months shorter than the known tissue culture-based transformation. The Excalibur Pink cultivar and two additional breeding lines, X-1042 and X-2541, were transformed using three different marker genes (benzyl alcohol acetyltransferase (BEAT) originating from Clarkia breweri, the feedback-insensitive bacterial gene AroG*, and the empty pART27 vector expressing a kanamycin-resistance cassette (nptII)). Genomic transformation was successful in all tested cases with transformation efficiency ranked from 0.2 to 2.9%, which is well in the range of results from Arabidopsis studies. Unlike Arabidopsis, in which floral-dipping transformation was efficient only at a pre-anthesis stage before ovary sealing, lisianthus flowers were transformed when dipping occurred 4 days pre-anthesis or 3-5 days post-anthesis with 1.5 and 3.7% efficiencies, respectively. Post-anthesis transformation occurred when the flower ovaries were sealed. Flower dipping of Excalibur Pink flowers with fluorescent Agrobacterium containing a GFP marker gene demonstrated Agrobacterium entrance into the sealed flower ovary through the open stigma and style tube. In this study, we demonstrated floral-dipping transformation of a commercial plant, lisianthus Excalibur Pink, occurring after sealing of the ovaries, probably via the stigma and wide open style tunnel.

Lilium�formolongi is a facultative long-day (LD) plant. Aiming to dissect the molecular regulation of the photoperiodic pathway, largely unknown in Lilium, we explored the CONSTANS/FLOWERING LOCUS T (CO/FT) module, a major regulatory factor in the external coincidence model of the photoperiodic flowering pathway in lily. We identified eight CONSTANS-LIKE (COL) family members in L.�formolongi, which could be divided into three types, according to their zinc-finger (B-box) protein domains. Type I included only LfCOL5, containing two B-box motifs. Type II contained six LfCOLs members that had only one B-box motif. Type III contained only LfCOL9 that showed a normal B-box and a second divergent B-box motif. Phylogenic analyses revealed that LfCOL5 was the closest to Arabidopsis CO. LfCOL5, LfCOL6 and LfCOL9 were up-regulated at the flowering induction stage under LDs, coinciding with an increase in LfFT1 expression. LfCOL5, LfCOL6 and LfCOL9 also showed obvious diurnal expression pattern for 3 d under LDs. However, under short-day (SD) conditions, the expression patterns of LfCOL5, LfCOL6 and LfCOL9 were variable and complex, with regard to the developmental stages and circadian rhythm. LfCOL5, LfCOL6 and LfCOL9 complemented the late flowering phenotype of the co mutant in Arabidopsis. Taken together, the results suggest that LfCOL5, LfCOL6 and LfCOL9 are involved in triggering flowering induction under LDs. LfCOL6 and LfCOL9 belong to types different from functional COL homologs in other plant species, illustrating the variation in phylogeny, evolution and gene function among LfCOL family members.

Large bulbs of Lilium longiflorum have an obligatory cold requirement to flower. Bulb cooling is widely used to induce and accelerate flowering. However, in-depth investigations of the effect of bulb cooling on major landmarks of plant development are lacking. It has been demonstrated that low temperature induces carbohydrate degradation, yet integrative studies on metabolic changes occurring in the bulb are not available. We detected that cold exposure mainly hastened bulb sprouting, rather than floral transition or blooming. Metabolite profiling of cooled and non-cooled bulbs was carried out, revealing cold-induced accumulation of soluble sugars, lipids and specific amino acids, and a significant reduction in tricarboxylic acid (TCA)-cycle elements. We observed that metabolic pathways located in the cytosol - including glycolysis, lipid synthesis and part of the gamma-Aminobutyric acid (GABA) shunt - were enhanced by cold exposure, while mitochondrial metabolism - namely the TCA cycle - was reduced by cold. We suggest a physiological model accounting for this metabolic discrepancy.

Floral induction in Tulipa gesneriana and Lilium longiflorum is triggered by contrasting temperature conditions, high and low temperature, respectively. In Arabidopsis, the floral integrator FLOWERING LOCUS T (FT), a member of the PEBP (phosphatidyl ethanolamine-binding protein) gene family, is a key player in flowering time control. In this study, one PEBP gene was identified and characterized in lily (LlFT) and three PEBP genes were isolated from tulip (TgFT1, TgFT2 and TgFT3). Overexpression of these genes in Arabidopsis thaliana resulted in an early flowering phenotype for LlFT and TgFT2, but a late flowering phenotype for TgFT1 and TgFT3. Overexpression of LlFT in L. longiflorum also resulted in an early flowering phenotype, confirming its proposed role as a flowering time-controlling gene. The tulip PEBP genes TgFT2 and TgFT3 have a similar expression pattern in tulip, but show opposite effects on the timing of flowering in Arabidopsis. Therefore, the difference between these two proteins was further investigated by interchanging amino acids thought to be important for the FT function. This resulted in the conversion of phenotypes in Arabidopsis upon overexpressing the substituted TgFT2 and TgFT3 genes, revealing the importance of these interchanged amino acid residues. Based on all obtained results, we hypothesize that LlFT is involved in creating meristem competence to flowering-related cues in lily, and TgFT2 is considered to act as a florigen involved in the floral induction in tulip. The function of TgFT3 remains unclear, but, based on our observations and phylogenetic analysis, we propose a bulb-specific function for this gene.

Background:Since ancient times people have been attracted by flowers and have invested precious energy to cultivate them even though there is no known reward for this costly behavior- in all cultures. How can this attraction be understood? To what extend is this relationship between people and flowers made up of evolutionary, cognitive, perceptual, emotional or socio-cultural components? Does it shift within different cultures? How can we better understand the attraction of people to flowers on both a cultural and universal level? Many questions in this field remain open.Objective:To understand culturally constructed versus universal-perceptual components of the attraction of people to flowers. To explore how different types of cultivated flowers (with different perceptual elements) are conceptualized within a specific culture.Methods:Using mixed methods, we investigated the comparative preference of 150 participants for four visually different flowers. We explored the reasons for the preferred choice of flower. Based on the above first phase, we investigated participants' perceptions of the concept of a generic 'flower' and compared this to a mandala. Based on this second phase, we moved into cultural, perceptual and psychological theories using a concept-map, to access cultural understandings of specific flowers.Results:All four different flowers were equally chosen as first choice and therefore we introduced the generic or universal concept of 'floweriness' that was characterized by enhancing calmness and happiness.On this level, the concept of the flower ranked higher for inducing happiness as compared to a mandala shape that induced more interest. The other three flowers were ranked and differentiated in terms of the cultural connotations that their different visual components aroused, within the context of Israeli culture.Conclusion:The results illustrate the interactive synergetic interplay between universal perceptual and specific cultural elements in relation to specific flowers. Together with this differentiation, the results also point to a central concept of “floweriness” that transcends the specific cultural connotations of specific flowers.

Madonna lily (Lilium candidum) is a flowering geophyte growing wild in Israel and in the neighboring region. In view of its holly character in the Christian culture, L. candidum has a great commercial potential as an ornamental crop. However, knowledge regarding its cultivation and the control of its flowering time is very limited. In this study, we aimed to define external factors affecting L. candidum flowering and characterized the developmental stages of the shoot apical meristem (SAM), under different temperature and photoperiod regimes. We found that in most cases, bulb or plant exposure to low temperature (4 °C, forcing) hastened floral transition and flowering in a quantitative manner, whereas day length had a negligible effect on these traits. These results suggest that vernalization is a major pathway regulating flowering time in L. candidum. We also characterized a novel phenomenon in which exposure of the bulb to low temperature led to a delay in bolting and flowering until the following season. We showed that the ability of a bulb to perceive cold exposure as signal for flowering hastening or as a delay was dependent on the SAM's developmental stage and was related to the season. During the summer, cold exposure applied to the SAM at the juvenile phase results in growth inhibition, while from the fall onward, when the meristem has reached its vegetative adult phase, cold exposure promotes bolting and flowering, according to the classic vernalization response. Exposure of the juvenile bulb to 12 °C promotes the transition of the SAM from juvenile to vegetative adult. In conclusion, we showed cold exposure of bulbs at the juvenile phase induced the inhibition of the bolting and flowering, while bulb cold exposure of bulbs at the vegetative adult stage promoted flowering. This study sheds light on the development and flowering physiology of L. candidum and can have applied outcomes for its cultivation as a cut flower crop.

Iron, one of the most important micronutrients in living organisms, is involved in basic processes, such as respiration and photosynthesis. Iron content is rather low in all organisms, amounting in plants to about 0.009% of dry weight. To date, one of the most accurate methods for measuring iron concentration in plant tissues is flame absorption atomic spectroscopy. However, this approach is time-consuming and expensive and requires specific equipment not commonly found in plant laboratories. Therefore, a simpler, yet accurate method that can be routinely used is needed. The colorimetric Prussian Blue method is regularly used for qualitative iron staining in animal and plant histological sections. In this study, we adapted the Prussian Blue method for quantitative measurements of iron in tobacco leaves. We validated the accuracy of this method using both atomic spectroscopy and Prussian Blue staining to measure iron content in the same samples and found a linear regression (R(2 )= 0.988) between the two procedures. We conclude that the Prussian Blue method for quantitative iron measurement in plant tissues is precise, simple, and inexpensive. However, the linear regression presented here may not be appropriate for other plant species, due to potential interactions between the sample and the reagent. Establishment of a regression curve is thus needed for different plant species.

In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the "indirect flowering" group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba, a temperate deciduous fruit tree belonging to the "direct flowering" group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25°C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues (ZjLFY and ZjAP1). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z. jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering.

In Lilium longiflorum, vernalization is both an obligatory requirement and the major factor affecting flowering time, however, little is known about the molecular regulation of this mechanism in Lilium and other flowering bulbs. Exposure of L. longiflorum bulbs to 9 weeks at 4 °C greatly promoted stem elongation within the bulb, floral transition and flowering. Subtraction libraries of vernalized (V) and non-vernalized (NV) bulb meristems were constructed. 671 and 479 genes were sequenced, from which 72 and 82 proteins were inferred for the NV–V and the V–NV libraries, respectively. Much lower transcription levels and putative gene functions were recorded in the NV–V libraries compared the V–NV libraries. However, a large number of genes annotated to transposable elements (TEs), represented more than 20% of the sequenced cDNA were expressed in the NV–V libraries, as opposed to less than 2% in the V–NV libraries. The expression profile of several genes potentially involved in the vernalization pathway was assessed. Expression of LlSOC1, the lily homologue of SUPPRESSOR OF OVER-EXPRESSION OF CO1 (SOC1), an important flowering gene in several plant species, found in the V–NV library, was highly up-regulated during bulb meristem cold exposure. The subtraction libraries provided a fast tool for relevant gene isolation.

The tolerance of perennial fruit crops to salinity is usually determined by analyzing tree performance in relation to EC or NaCl concentration in the soil and/or irrigation water or in relation to the period during which the plants were grown under salinity conditions. In response to these conditions, toxic ions accumulate in the plant over time, but very few studies have sought to correlate ion concentration directly to tree vegetative and/or reproductive performances. We investigated the utility of a direct short-term approach that involved “loading” Ziziphus jujuba trees with different levels of NaCl and determining the correlation between the accumulation of specific toxic ions in the leaves, flowers and roots (Na+ and Cl−) and the change in tree vegetative and reproductive performance. Z. jujuba cultivar ‘Ben-Li’ trees planted in pots were irrigated with four salinity levels: 13.2, 31.7 and 61.9 mM NaCl and tap water (1.6 mM Na+ and 1.1 mM Cl−) as control. The salinity threshold for normal growth and flowering was found to be 0.40% Na+ and 2.68% Cl− in leaves (% of dry weight), 0.27% Na+ in roots, and 0.10% Na+ and 0.52% Cl− in flowers. Na+ accumulation was correlated with impairment in six of the seven growth and flowering traits tested, while Cl− was found to be correlated to only three of these seven traits, suggesting that for the salinity range tested Na+ is the more toxic ion for Z. jujuba trees. The present study shows that the rise in toxic ion concentrations in the plant tissues correlates with changes in flowering and tree growth, thereby making it possible in the short term both to determine the salinity threshold above which there is a reduction in yield and to predict in the longer term changes in tree performance as a function of ion accumulation.

Lilium candidum L., commonly known as the Madonna lily, is a wild Lilium species with medicinal properties and excellent potential as an ornamental crop, but one that has been scarcely investigated. The aim of this research was to study (1) tissue culture propagation of L. candidum bulblets, (2) early bulblet development, and (3) the effect of temperature and bulblet weight on bulblet and plant growth and meristem development. An investigation of the effect of explant type and temperature on in vitro bulblet propagation showed that scales were the most efficient explants for in vitro propagation and that exposing the regenerating bulblets to 15°C for 4 wk increased bulblet weight but reduced the number of bulblets produced. For bulblets planted in soil after 12 wk of exposure to 15°C or 25°C, the fastest growth was observed in the bulblets that had been exposed to 15°C and that had a larger initial size. Histological examination showed that young in vitro-grown bulblets had a rudimentary meristem comprising few cells with no layer organization. After 12 wk of growth, all bulblets showed a layered meristem, regardless of bulblet size or exposure to 15°C. However, an increased amount of leaf primordia was detected in larger bulblets. Furthermore, the histological examination revealed that in L. candidum, as opposed to other lily species, there had been no real "phase change" in the meristem and that the phase change from juvenile to vegetative adult occurred at a much later stage in L. candidum than in other species.

Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV.

During the year 2002, two new diseases with unknown etiologies were detected in cucurbit crops in Israel. One disease was detected in squash fields throughout the country, while the second appeared in a single watermelon plot in the south, just outside the city of Elat. The infected watermelon plot was eradicated, but nonetheless the new disease spread throughout the country and today it is present in all the watermelon production areas. Both diseases were associated with elevated whitefly populations. Indeed, it was found that both are transmitted only by whiteflies, and are incited by two begomoviruses. Both viruses were cloned and sequenced, and were identified as Watermelon chlorotic stunt virus (WmCSV) and Squash leaf curl virus (SLCV). The host range of the Israeli WmCSV isolate (WmCSV-IL) was determined and resembles the host range of the three other known WmCSV isolates (from Yemen, Sudan, and Iran), but with a few differences. Although no genetic resistance to WmCSV was observed in cultivated wat...

The antiviral activity of Callissia fragrans and Simnondsia chinensis aquatic and ethanol leaf extracts, as well as purified fractions from these extracts was studied against herpetic viruses in vitro. Ethanol extract of C. fragrans effectively inhibited the infection of Vero cells by HSV-1, HSV-2 in vitro, while its aquatic extract inhibited only VZV. Although S. chinensis leaf extract strongly inhibited all studied viruses, the selectivity index of this extract was very low, due to its high toxicity. However, the majority of its fractions showed low toxicity and higher antiviral activity and therefore very high SI. Strong interactions between virus and extracts were found.

The effects of shading on lisianthus (Eustoma grandiflorum) floral transition, plant development, flower yield and quality, and content of starch and soluble sugars were assessed in three cultivars, over two consecutive years. Shading nets affording 67% or 88% reduction in light intensity, were fitted at planting in the greenhouse for periods ranging from 3 to 8 weeks. Meristem morphology at floral transition was characterized by apical meristem widening and the appearance of two bract primordia. Floral transition time was affected by cultivars, but in general, longer and heavier shade treatments delayed floral transition; the longest delay (6 weeks) being recorded in Mariachi White under 88% shade for 7 weeks or under a combined shade treatment of 88% for 3 weeks followed by 67% for 5 weeks. Despite interactions between cultivar and shade treatment, consistent trends were discerned: the heaviest and most prolonged shading reduced yield (up to 40%), cut stem length (up to 15%), and number of flower buds/stem (up to 26%), within cultivar. Total carbohydrates levels were very low, and it is questionable whether changes observed in carbohydrate quantity following shade treatments had any effect on plant growth or flower yield. Rather, it appears that lisianthus is very dependent on current photosynthesis, so that even a brief shading interlude could reduce branching and flower quality. It may be concluded that the intensive shading usually applied is detrimental for lisianthus.

Lilium candidum is a rare geophyte with a tall stem and large, fragrant, pure white flowers, found in Greece, Turkey, Syria, Lebanon, and Israel. It is an endangered species in the Israeli flora, with a high priority for conservation. Characterization and conservation of wild ecotypes are essential for preserving this important plant. We have established a collection of wild L. candidum ecotypes collected at four locations in Kelach Creek in Mount Carmel and in the Kziv Creek in the Galilee, and assessed flowering-related traits in plants growing in their natural habitats and under controlled conditions in Be'er Sheva for two consecutive years. Variation among locations was observed for flowering time and stem length, but not for the number of flowers per stem. Plants grown in the greenhouse flowered consistently several weeks earlier and produced more flowers per stem than under natural conditions. Morphological differences in flower shape between ecotypes from Kelach and Kziv Creek were apparent. The va...

In roses, bending of the peduncle during flower development – “bent peduncle phenomenon” (BPP) – results in the production of a series of developmental aberrancies. Detailed characterization of BPP revealed that the typical bending is intrinsically related to developmental features, i.e., the presence of an enlarged sepal appearing as a phylloid structure, floral organ conversions, fasciation of the stem and the higher incidence of BPP in axillary stems developing from BPP stems than from normal stems. The sclerenchymal tissue of BPP stems exhibited larger cells and thinner cell walls than those of normal stems, which may facilitate the bending process. BPP-like bending could be induced by external auxin application and inhibited by auxin transport inhibitors. Thus, in BPP auxin appears to be involved in differential growth, thereby inducing bending. However, there were no differences in endogenous IAA content between the upper and lower sides of bent peduncles, indicating that the asymmetric IAA distribution may be transient. This study strongly suggests that BPP is a developmental process, occurring during the meristematic stage of flower formation, possibly involving auxin distribution, which affects stem bending and fasciation.

Novel cationic amphiphilic compounds were prepared from vernonia oil, a natural epoxidized triglyceride, and studied with respect to vesicle formation, encapsulation of biomaterials such as DNA, and their physical stability and transport through isolated plant cuticle membranes. The amphiphiles studied were a single-headed compound III (a quaternary ammonium head group with two alkyl chains) and a triple-headed compound IV, which is essentially three molecules of compound III bound together through a glycerol moiety. Vesicles of the two amphiphiles, prepared by sonication in water and solutions of uranyl acetate or the herbicide 2,4-D (2,4-dichloropenoxy acetic acid), were examined by TEM, SEM, AFM, and confocal laser systems and had a spherical shape which encapsulated the solutes with diameters between 40 and 110 nm. Vesicles from amphiphile IV could be made large enough to encapsulate a condensed 5.2 kb DNA plasmid (pJD328). Vesicles of amphiphile IV were also shown to pass intact across isolated plant cuticle membranes and the rate of delivery of encapsulated radio-labeled 2,4-D through isolated plant cuticle membranes obtained with these vesicles was clearly greater in comparison to liposomes prepared from dipalmitopyl phosphatidylcholine (DPPC) and the control, nonencapsulated 2,4-D. Vesicles from amphiphiles III and IV were found to be more stable than those of liposomes from DPPC. The data indicate the potential of vesicles prepared from the novel amphiphile IV to be a relatively efficient nano-scale delivery system to transport DNA and other bioactive agents through plant biological barriers. This scientific approach may open the way for further development of efficient in vivo plant transformation systems.

Protocols for in vitro regeneration and production of in vitro-propagated plants and a transformation system were developed for Mirabilis jalapa (Nyctaginaceae). Among the types of explants and the different media tested, consistent shoot regeneration was obtained only from nodal segments grown in a regeneration medium consisting of Murshashige and Skoog medium supplemented with 2 mg l−1 6-benzyladenine, 2 mg l−1 zeatin and 1 mg l−1 indole acetic acid. Regeneration efficiency was dependent on the type of plant – white or pink flowers – used as the source of explants. Stable transformation was obtained following inoculation of nodal segments with Agrobacterium tumefasciens strain EHA105, which harbours the binary plasmid pAD1339 containing both nptII and gus genes under the control of the 35S promoter. Transformation was confirmed by PCR and Southern blot analysis of genomic DNA from mature regenerated plants. β-Glucuronidase (GUS) activity was observed only in tissues regenerated from in vitro-grown plants and not in tissues originating from greenhouse-grown plants. GUS expression was not uniform in regenerated leaves and showed a chimera pattern.

Lisianthus ( Eustoma grandiflorum ) is an ornamental plant with beautiful but scentless flowers. In an attempt to induce a fragrance in their flowers, lisianthus plants were transformed with the Clarkia breweri gene coding for benzyl alcohol acetyltransferase ( BEAT ), catalyzing the synthesis of the volatile compound benzyl acetate under the regulation of the CaMV35S promoter. An external supply of benzyl alcohol induced five to seven times higher production of benzyl acetate in detached flowers and leaves of transgenic lisianthus plants, compared to non-transformed plants. No benzyl acetate was detected in tissues of both control and transgenic plants fed with water. When fed with additional alcoholic compounds, i.e. hexanol, benzyl alcohol, isoamyl alcohol, phenethyl alcohol, and cinnamyl alcohol, assumed to be used as substrates by BEAT, transgenic in vitro -grown lisianthus plantlets produced significantly higher levels of acetates than control plants. These results demonstrate the possibility of producing substrate-dependent acetates in transgenic lisianthus plants, which could lead to induction of new aromas.

Lilium longiflorum (Easter lily) vegetative propagation occurs through production of underground bulbs containing apical and axillary meristems. In addition, sexual reproduction is achieved by flowering of elongated shoots above the bulb. It is generally accepted that L. longiflorum has an obligatory requirement for vernalisation and that long day (LD) regime hastens flowering. However, the effect of bulb size and origin, with respect to axillary or apical meristems on flowering, as well as the interactions between these meristems are largely unknown. The aim of this study was to explore the effect of bulb size, vernalisation and photoperiod on L. longiflorum flowering. To this end, we applied vernalisation and photoperiod treatments to the different bulb sizes and used a system of constant ambient temperature of 25 °C, above vernalisation spectrum, to avoid cold-dependent floral induction during plant growth. Vernalisation and LD hasten flowering in all bulbs. Large, non-vernalised bulbs invariably remained at a vegetative stage. However, small non-vernalised bulbs flowered under LD conditions. These results demonstrate for the first time that cold exposure is not an obligatory prerequisite for L. longiflorum flowering, and that an alternative flowering pathway can bypass vernalisation in small bulbs. We suggest that apical dominance interactions determine the distinct flowering pathways of the apical and axillary meristems. Similar floral induction is achieved in propagated bulblets from scaling. These innovative findings in the field of geophyte floral induction represent valuable applicative knowledge for lily production.

Morphological and genetic analyses were applied on 37 saltgrass (Distichlis spicata) accessions collected from distant locations throughout the American continent in order to: 1) develop and identify morphologic and genetic profiles for the saltgrass genotypes; 2) characterize the genetic distance among saltgrass accessions within the given germplasm collection; and 3) identify a possible linkage between patterns of genetic and eco-geographical parameters. Analysis based on 70 RAPD markers revealed broad polymorphism among the genotypes and enabled their individual characterization. A UPGMA dendrogram clustered the genotypes into groups according to a general pattern of their geographical origin. Yet, only the group of Californian accessions was significantly distinct from other groups, as determined by χ2 tests. Various statistical analyses indicated that only minor genetic differences existed between seashore and desert saltgrass genotypes, supporting that these two eco-geographical types belong to the same species, Distichlis spicata. Our results suggest that genetic interactions exist between geographically distant saltgrass populations, in spite of the dominance of clonal reproduction in this species. The contribution of dioecy, seed production, and epizoochory to the distribution patterns of saltgrass is discussed at the geographic and at the genetic levels.

Tomato (Lycopersicon esculantum) ASR1 (abscisic acid stress ripening protein), a small plant-specific protein whose cellular mode of action defies deduction based on its sequence or homology analyses, is one of numerous plant gene products with unknown biological roles that become over-expressed under water- and salt-stress conditions. Steady-state cellular levels of tomato ASR1 mRNA and protein are transiently increased following exposure of plants to poly(ethylene glycol), NaCl or abscisic acid. Western blot and indirect immunofluorescence analysis with anti-ASR1 antibodies demonstrated that ASR1 is present both in the cytoplasmic and nuclear subcellular compartments; approx. one-third of the total ASR1 protein could be detected in the nucleus. Nuclear ASR1 is a chromatin-bound protein, and can be extracted with 1 M NaCl, but not with 0.5% Triton X-100. ASR1, overexpressed in Escherichia coli and purified to homogeneity, possesses zinc-dependent DNA-binding activity. Competitive-binding experiments and SELEX (systematic evolution of ligands by exponential enrichment) analysis suggest that ASR1 binds at a preferred DNA sequence.

The effects of potassium chloride (KCl) as a potassium (K) source in fertigation solution on growth, yield and quality of tomato (cv. Durinta) in a controlled greenhouse were compared with potassium nitrate (KNO3)—the conventional K source for vegetable fertigation. The treatments consisted of four levels of KCl: (1) 0% KCl (100% KNO3), (2) 40% KCl (40% KCl and 60% KNO3), (3) 60% KCl (60% KCl and 40% KNO3), and (4) 100% KCl (0% KNO3) in fertigation solution in the season 1999–2000. In 2000–2001, early (12 days after planting) and late (47 days after planting) applications of 100% KCl and 0% KCl were tested. The concentrations of K and other major nutrients were similar in all the treatments. Ammonium nitrate (NH4NO3), calcium nitrate [Ca(NO3)2] and nitric acid (HNO3) were used as nitrogen (N) sources in KCl treatments. Electrical conductivity (EC) of all solutions ranged from 1.8 to 2.1 dS m−1; pH range was from 6.6 to 7.1. Perlite was used as a neutral growing medium. Plant height, time to anthe...

Floral transition was studied in lisianthus [Eustoma grandiflorum (Raf.) Shinn.] plants grown in a greenhouse at two planting times (winter and summer) under two photoperiod regimes: long day (LD) and short day (SD), 16 h/8 h and 8 h/16 h (light/dark), respectively. Morphological analyses of the flower meristem of the lisianthus cultivar ‘Heidi Deep Blue’ revealed three distinct stages of development: (1) sepal primordia, (2) petal and stamen primordia (almost simultaneously), and (3) carpel primordia. The appearance of sepal primordia was taken to mark the floral transition stage. Floral transition was hastened in summer-grown plants and under LD treatment, as expressed by a reduction in both the number of nodes and the time from planting. Stem length from base of plant to floral meristem, as measured at floral transition, was similar in all treatments, regardless of the number of nodes produced. At both planting dates, SD induced a higher number of flowers per inflorescence than LD. This report thus describes the direct effect of environmental factors on floral transition in lisianthus.

The long-term effect of saline water irrigation on flower yield and quality was investigated in three herbaceous cut flower crops of commercial importance, the Emily cultivars of Japanese limonium, Trachelium caeruleum and Eustoma grandiflorum (lisianthus), and in two bulb species, Hippeastrum hybridum and Ornithogalum arabicum . Among the tested crops, limonium showed the highest resistance to salinity. Irrigation water with an electrical conductivity of up to 11.5 dS m −1 had little or no effect on stem yield and length of limonium flowering stems. In Trachelium , salinity had no effect on the yield of flowering stems or the size of the inflorescence, but it markedly reduced stem weight and length. The concomitant reduction in the number of nodes to flowering was reflected in earlier flower initiation. Since delayed flower differentiation and over-elongation of Trachelium stems is a serious problem during the winter months, application of mildly saline irrigation for winter production could be used to induce earlier flower initiation and to control stem height. In lisianthus subjected to salinity from bud appearance onwards, a salinity level of 6.0 dS m −1 increased stem weight and the number of flowers per stem without affecting other quality parameters. The work carried out with Trachelium and lisianthus, although limited, indicates that salinity may be used for improving the quality of some cut flowers. In contrast to its beneficial effect on the herbaceous species, salinity led to a significant reduction of bulb, leaf, and root weight of the two bulbous species, H. hybridum and O. arabicum .

The control of flowering time is an essential issue for most ornamentals. The molecular basis of this trait has been extensively studied in model plants, yielding useful information on the role of various genes which could potentially be used in heterologous systems. For instance, overexpression of the meristem-identity gene LEAFY (LFY) from Arabidopsis has previously been shown to be sufficient to reduce flowering time in plants as diverse as Arabidopsis itself, tobacco and aspen. We tested the effect of LFY overexpression on flower development in lisianthus plants transformed with LFY cDNA under constitutive control of the 35S CaMV promoter (35S::LFY, provided by Dr. Weigel). F1 progenies from two different transformed plants flowered in average one to two weeks earlier than control plants at two consecutive years. The number of nodes to the first flower as well as the number of flowers per inflorescence were reduced in the early-flowering plants, suggesting a faster flower development. Normal fertile flowers were obtained from all plants. These results indicate that flowering time can me manipulated by transgenic means. Lisianthus transformations with genes acting upstream to LFY are currently being made. The possibility of introducing a fragrance to lisianthus flowers by genetic engineering is being investigated using genes from the scented plant Clarkia breweri: Acetyl CoA benzyl alcohol acetyl transferase (BEAT) and S-linalool synthase (LIS). These two genes code for key enzymes in the synthesis of the aroma compounds benzyl acetate and S-linalool respectively. Aroma modification of the fruit of transgenic tomato plants carrying a LIS construct has already been demonstrated. The effect of BEAT and LIS transgenes on tobacco and lisianthus fragrance is under investigation.

SummaryAdducin is a cytoskeletal protein that can functionin vitroto bundle F-actin and to control the assembly of the F-actin/spectrin cytoskeletal network. TheDrosophila Adducin-like(Add) locus (also referred to ashu-li tai shao(hts)) encodes a family of proteins of which several are homologous to mammalian adducin (Dinget al., Proc. Natl. Acad. Sci. USA90, 2512–16, 1993; Yue & Spradling,Genes Dev.6, 2443–54, 1992). We report the identification of two novel adducin isoforms: a 95 × 103Mrform (ADD-95) and an 87 × 103Mrform (ADD-87). We present a detailed analysis of the distribution patterns of ADD-95 and ADD-87 during oogenesis and embryogenesis. The isoforms are co-expressed in several cell- and tissuetypes; however, only ADD-87 is present in mid- to late-stage oocytes. ADD-87 is present throughout the oocyte cortex at stages 9 and 10 of oogenesis but is detectable only at the anterior pole from stage 11 onward, correlated with localisation ofAdd-htsmRNA first to the cortex and then to the anterior pole of the oocyte. ADD-87 co-localises with F-actin and spectrin in the cortex of the oocyte through stage 10 of oogenesis, consistent with a possible role in cytoskeletal assembly or function predicted by mammalian studies.

Adducin is a cytoskeletal protein that can function in vitro to bundle F-actin and to control the assembly of the F-actin/spectrin cytoskeletal network. We previously reported cloning of the Drosophila Adducin-like (Add) locus [Ding et al., 1993] also referred to as hu-li tai shao (hts) [Yue and Spradling, 1992], and identification of two adducin-related protein isoforms: a 95 x 10(3) Mr form (ADD-95) and an 87 x 10(3) Mr form (ADD-87) [Zaccai and Lipshitz, 1996]. ADD-87 protein is present throughout the oocyte cortex at stages 9 and 10 of oogenesis but is restricted to its anterior pole from stage 11 onward. This ADD-87 protein localization is preceded by localization of Add-hts mRNA first to the cortex and then to the anterior pole of the oocyte. Mutation of the swallow gene results in delocalization of Add-hts mRNA and ADD-87 protein from the cortex of stage 9 and 10 oocytes, and from the anterior pole of later stage oocytes. Early embryos produced by swallow or Add-hts mutant females have severe defects in the distribution of F-actin and spectrin as well as abnormalities in nuclear division, nuclear migration, and cellularization. In addition to their cytoskeletal defects, embryos produced by swallow females have an abnormal anterior pattern because bicoid mRNA is delocalized from the anterior pole. In contrast, bicoid mRNA is still found at the anterior of embryos produced by Add-hts mothers. Thus swallow functions to restrict bicoid mRNA and Add-hts mRNA to the cortex of the oocyte. Cortical restriction of Add-hts mRNA and protein is required for the normal structure and function of the early embryonic F-actin/spectrin cytoskeleton. A defective embryonic cytoskeleton can be induced in either of two ways: (1) by delocalization of functional ADD from the oocyte cortex (as in swallow mutants), or (2) by reduction of ADD function while retaining its normal cortical localization during oogenesis (as in Add-hts mutants).

Globalization of the Flower Bulb Industry August A. De Hertogh, Johan van Scheepen, Marcel Le Nard, Hiroshi Okubo, and Rina Kamenetsky Taxonomy and Phylogeny Alan W. Meerow Biodiversity of Geophytes: Phytogeography, Morphology, and Survival Strategies Rina Kamenetsky Botanical and Horticultural Aspects of Major Ornamental Geophytes Hiroshi Okubo and Dariusz Sochacki Introduction and Development of New Ornamental Geophytes Mark P. Bridgen Breeding and Genetics of Ornamental Geophytes Jaap M. van Tuyl, Paul Arens, and Agnieszka Marasek-Ciolakowska Biotechnology for the Modification of Horticultural Traits in Geophytes Kathryn K. Kamo, Frans A. Krens, and Meira Ziv Florogenesis Rina Kamenetsky, Michele Zaccai, and Moshe A. Flaishman Dormancy Hiroshi Okubo Propagation of Ornamental Geophytes: Physiology and Management Systems Anna Bach and Dariusz Sochacki Production Chain, Forcing Physiology, and Flower Production Systems William B. Miller Postharvest: Cut Flowers and Potted Plants Michael S. Reid and Cai-Zhong Jiang Sustainable Production and Integrated Management: Environmental Issues Gary A. Chastagner, Gordon R. Hanks, Margery L. Daughtrey, Iris Yedidia, Timothy W. Miller, and Hanu R. Pappu Geophyte Research and Production in Asia Seiichi Fukai Geophyte Research and Production in Brazil Antonio F. C. Tombolato, Roberta P. Uzzo, Antonio H. Junqueira, Marcia da S. Peetz, and Giulio C. Stancato Geophyte Research and Production in Chile Eduardo A. Olate and Flavia Schiappacasse Geophyte Research and Production in New Zealand Keith A. Funnell, Ed R. Morgan, Glenn E. Clark, and Joo Bee Chuah Geophyte Research and Production in South Africa Graham D. Duncan Geophyte Research and Production in Turkey Ibrahim Baktir Conclusions and Future Research Rina Kamenetsky, Gary A. Chastagner, and Hiroshi Okubo Appendix: Botanical Names Mentioned in This Book Index

The antiviral activity of Callissia fragrans and Simnondsia chinensis aquatic and ethanol leaf extracts, as well as purified fractions from these extracts was studied against herpetic viruses in vitro. Ethanol extract of C. fragrans effectively inhibited the infection of Vero cells by HSV-1, HSV-2 in vitro, while its aquatic extract inhibited only VZV. Although S. chinensis leaf extract strongly inhibited all studied viruses, the selectivity index of this extract was very low, due to its high toxicity. However, the majority of its fractions showed low toxicity and higher antiviral activity and therefore very high SI. Strong interactions between virus and extracts were found.

The inheritance of grain protein percentage and of grain weight were studied by crossing common and durum wheat cultivars with hexaploid and tetraploid breeding lines that excel in grain protein percentage. All high protein lines were descendants of the tetraploid wild emmer Triticum turgidum var. dicoccoides. One hexaploid cultivar was also crossed with a high-protein var. dicoccoides genotype. All crosses were made between low- and high-protein genotypes and were carried out reciprocally for any combination of genotypes; some of them between genotypes of the same ploidy level and some between hexaploid and tetraploid lines. Weight and protein percentage were determined in selfed and crossed grains that developed on the same spike. Mean weight and protein percentage were also determined in F2 grains of all crosses of the same ploidy level, either tetraploid or hexaploid. At any ploidy level, F1 grains resembled the selfed grains of the mother plant both in grain weight and in grain protein percentage, indicating a major maternal effect on both traits. F2 grains had similar grain weight to the heavy-grained parent, and their protein percentage was close to the midparents value. However, a slight indication of cytoplasmic inheritance of grain protein percentage was found in the comparison between most pairs of F2 reciprocals. The interspecific crosses (hexaploid with tetraploid combinations) yielded shrivelled seeds with highly reduced weight but relatively unchanged protein percentage. Weight reduction in the shrivelled hybrid grains (compared with the selfed ones) was more severe when the mother plant was hexaploid rather than tetraploid. The significance of the different tissues in determining grain weight and protein percentage is discussed.Key words: grain weight, grain protein percentage, maternal effect, paternal effect, reciprocal crosses, wheat, Triticum aestivum, Triticum turgidum var. dicoccoides.