Narcissus Cultivars Research Articles

FISH and GISH reveal genome composition of popular Narcissus cultivars and the possible ways of their origin

FISH and GISH reveal genome composition of popular Narcissus cultivars and the possible ways of their origin

Emergence of Corona Is Independent of the Four Whorls of Floral Organs in Narcissus tazetta

Plants of the genus Narcissus are well-known for their characteristic corona morphology, which structural origins have been a bone of contention among scholars. With "Jinzhanyintai" (JZ) and "Yulinglong" (YLL)-two major close-originated cultivars of Chinese narcissus (Narcissus tazetta L. var. chinensis Roem)-as materials, anatomic observation was made on floral organs during corona morphogenesis by dissection with hands under a stereomicroscope, paraffin section, scanning electron microscopy, and high-resolution X-ray tomography. It was uncovered that corona primordia of both cultivars appeared following the end of the differentiation of other floral organs, with differentiation sites located at the inner wall of the juncture of the base of tepals and the upper margin of the hypanthium. Affected by staminal filaments, the corona primordia of JZ experienced a three-stage differentiation process, namely blockage from the second whorl of stamens, blockage from the first whorl of stamens, and healing of corona primordia. However, the expanded spatial structure of the first whorl of petal-like stamens blocked the path of differentiation of YLL corona primordia, giving rise to slow differentiation of the corona primordia at the base of the first whorl of petal-like stamens and malformed differentiation of the corona primordia in the interval between the two whorls of petal-like stamens. Thus, a fragmented structure consisting of typical and fragmented coronas was formed. Furthermore, petal-like stamens of YLL in the lower part had a corona-like morphology. The spatio-temporal specificity of corona differentiation convincingly demonstrates that the corona is a structure independent of and different from the typical four whorls of floral organs, but also highly correlated with stamen.

Genetic variations of Narcissus tazetta and selected Narcissus cultivars based on the sequence analysis of nrITS and trnL-IS-trnF regions

Genetic variations of Narcissus tazetta and selected Narcissus cultivars based on the sequence analysis of nrITS and trnL-IS-trnF regions

Nuclear DNA Content, Selected Morphological and Anatomical Traits of Narcissus Cultivars and Breeding Clones

The genus Narcissus belongs to the family Amaryllidaceae. This genus has been the subject of numerous cytological and cytometric studies and have shown enormous variation in terms of genome size, ploidy level, and even the basic chromosome number. The basic chromosome numbers are 5 or 7, but 10, 11, and 12 have been recorded as well. Most narcissus cultivars are euploid tetraploids. There are also numerous triploids. Some cultivars are aneuploid such as tetraploids or triploids, with missing chromosomes or possessing additional chromosomes. Due to their very complex parentage, cultivars have various numbers of chromosomes not found in the species. In this publication, we present a study on the genome size and assessment of the likely ploidy level of 38 cultivars and breeding clones of Narcissus in relation to their selected morphological traits and information on their parental forms. For the first time, 12 Polish cultivars and breeding clones of narcissus were the subject of such an evaluation. Perianth diameter, leaf length, and width were evaluated and rated with notes according to the descriptor of the International Union for the Protection of New Varieties of Plants. Stomatal density and stomata length were measured using light microscopy. Analysis of genome size was carried out using flow cytometry. For three selected genotypes, the chromosome number was counted. Our results lead to the general conclusion that the morphological traits studied and nuclear DNA content can be useful for determining the possible ploidy level of narcissi. The information on the origin and parental forms of narcissi can be helpful in determining the ploidy level of narcissi. However, clear confirmation of ploidy level requires verification of chromosome number and preferably karyotyping. The results obtained are a prelude to further studies.

Analyzing Narcissus genome compositions based on rDNA loci on chromosomes and crossing-compatibility of 16 cultivars

Sixteen Narcissus cultivars were analyzed for their loci of 45S rDNA and 5S rDNA on mitotic metaphase chromosomes using fluorescence in situ hybridization (FISH), their male fertility by testing their pollen germination and female fertility based on their crossability. The results and analysis showed that thirteen cultivars, including ‘Queen's Day’, ‘Pink Charm’, ‘Stadium’, ‘Mount Hood’, ‘Eline’, ‘Accent’, ‘Dutch Master’, ‘Flower Parade’, ‘Replete’, ‘Las Vegas’, ‘Flower Surprise’, ‘Ice Follies’ and ‘Easter Born’, were autotetrapliod (2n = 4x = 28 = EEEE) and they were obtained from chromosome doubling, because they had similar FISH karyotypes and their male and female fertility match with autotetraploid; For similar reasons, Chinese Narcissus ‘Jinzhanyintai’ was autotriploid (2n = 3x = 30 = AAA) caused by unilateral sexual polyploidization, ‘Pink Parasol’ was identified as allotetraploid (2n = 4x = 30 = CCDD), and ‘Bridal Crown’ had one A genome and one B genome, meaning it was selected from interspecific hybridization (2n = 2x = 17 = A + B). It was concluded that FISH with rDNA probes was powerful tool to analyze Narcissus genomes. The results would be valuable to guide breeding in Narcissus.

Basal Rot of Narcissus: Understanding Pathogenicity in Fusarium oxysporum f. sp. narcissi.

Fusarium oxysporum is a globally distributed soilborne fungal pathogen causing root rots, bulb rots, crown rots and vascular wilts on a range of horticultural plants. Pathogenic F. oxysporum isolates are highly host specific and are classified as formae speciales. Narcissus is an important ornamental crop and both the quality and yield of flowers and bulbs can be severely affected by a basal rot caused by F. oxysporum f. sp. narcissi (FON); 154 Fusarium isolates were obtained from different locations and Narcissus cultivars in the United Kingdom, representing a valuable resource. A subset of 30 F. oxysporum isolates were all found to be pathogenic and were therefore identified as FON. Molecular characterisation of isolates through sequencing of three housekeeping genes, suggested a monophyletic origin with little divergence. PCR detection of 14 Secreted in Xylem (SIX) genes, previously shown to be associated with pathogenicity in other F. oxysporum f. spp., revealed different complements of SIX7, SIX9, SIX10, SIX12 and SIX13 within FON isolates which may suggest a race structure. SIX gene sequences were unique to FON and SIX10 was present in all isolates, allowing for molecular identification of FON for the first time. The genome of a highly pathogenic isolate was sequenced and lineage specific (LS) regions identified which harboured putative effectors including the SIX genes. Real-time RT-PCR, showed that SIX genes and selected putative effectors were expressed in planta with many significantly upregulated during infection. This is the first study to characterise molecular variation in FON and provide an analysis of the FON genome. Identification of expressed genes potentially associated with virulence provides the basis for future functional studies and new targets for molecular diagnostics.

Performance of different narcissus cultivars in Izmir ecological conditions

Performance of different narcissus cultivars in Izmir ecological conditions

The effect of bulb weight on salinity tolerance of three common Narcissus cultivars

Daffodils [Narcissus sp. (L.) Amaryllidaceae] are popular landscaping plants and cut flowers. The daffodil cultivars ‘Dutch Master’, ‘Ice Follies’, and ‘Tete-a-Tete’ are considered highly tolerant to salinity by maintaining visual quality at NaCl induced electrical conductivity (EC) greater than 6 dS⋅ m−1. In geophytes, the bulb can act as a buffer for stress, and in this study we wanted to determine how the bulb contributes to salinity tolerance in these three daffodil cultivars. Bulbs were divided into three weight categories and exposed to irrigation salinities of 0, 50 and 100 mM NaCl during chilling, active growth and flowering. Regardless of the level of salinity exposure, plants (regardless of salinity or cultivar) with large bulbs grew at least twice the rate as plants from small bulbs grown at the same salinity. Flowers lasted on average 2 days longer in large bulb plants compared to small bulb plants. The ability to flower was impacted by cultivar and bulb size, with the least flowering occurring in small bulb ‘Dutch Master’ plants. In contrast, salinity was the main factor affecting leaf osmotic potential and relative water content (both decreased by 13%), antioxidant capacity (increased by 11%), gas exchange (reduced 50–75%), and cation uptake (5 fold increase in NaCl treatments). Although increasing bulb size did not improve all plant factors impacted by salinity, increases in initial bulb size improved overall growth at all levels of salinity and allowed the plants to maintain flower production and visual quality.

Postharvest life of different cultivars of Narcissus (daffodil) as influ-enced by various preservative solutions

Post harvest life has always being of critical importance in high value flower crops. Our investigation was concerned in evaluating the varietal response of different preservative soloutions on post harvest life of Narcissus (daffodil). The effects of the application of citric acid, aluminium sulphate, silver thiosulphate and calcium chloride at three different levels 0, 100 ppm, 200 ppm along with carbohydrate source sucrose 4% on different floral attributes of Narcissus (daffodil) cultivars California, Pheasants eye and Acetea were stud-ied. The recorded traits included water loss/water uptake ratio, scape length, cup depth, cup diameter, relative water content and membrane stability index. Results of this study showed that within all treatments aluminium sulphate + sucrose 4% showed the best effect. Among the cultivars evaluated California proves best in term of parameters studied (overall post harvest life). The minimum values for these traits were recorded in the untreated control.

Composition of Carotenoids and Flavonoids in Narcissus Cultivars and their Relationship with Flower Color.

Narcissus is widely used for cut flowers and potted plants, and is one of the most important commercial bulbous flowers in the floricultural industry. In this study, ten carotenoid and eighteen flavonoid compounds from the perianths and coronas of fifteen narcissus cultivars were measured by HPLC–APCI-MS/MS and UPLC-Q-TOF-MS/MS. Among these, six carotenoids, a total of seventeen flavonols and chlorogenic acid were identified in narcissus for the first time. A multivariate analysis was used to explore the relationship between flower color and pigment composition. We found that all-trans-violaxanthin and total carotenoid content were the main factors that affected flower color. These investigations could provide a global view of flower color formation and a theoretical basis for hybridization breeding in narcissus.

Karyotype Analysis in seven cultivars ofNarcissusspp.

We investigated the chromosome number and karyotype in seven cultivars of Narcissus spp. using the traditional squash method. The result indicated that all seven cultivars were diploid and the basic chromosome numbers in these seven cultivars were n = 12 and 14. The karyotype was 2B for all seven cultivars. Six of seven cultivars consisted of m and sm chromosome, and only one cultivar contains st chromosome. The detailed karyotypes of the seven cultivars are as follows: Arkle: 2n = 2x = 28 = 3m + 11sm, index of the karyotypic asymmetry (As·k) = 66.57 %; Fortissimo: 2n = 2x = 28 = 4m + 10sm, As·k = 66.60 %; Pink Charm: 2n = 2x = 28 = 3m + 10sm + 1st, As·k = 66.62 %; Mary Bcharmon: 2n = 2x = 24 = 5m + 7sm, As·k = 64.56 %; Barret Browing: 2n = 2x = 24 = 6m + 6sm, As·k = 65.73 %; Romance: 2n = 2x = 24 = 2m + 10sm, As·k = 65.64 %; Dutch Master: 2n = 2x =24 = 3m + 9sm, As·k = 65.95 %. Our results indicated that the karyotype analysis combined with morphological characters could assist to classify the taxonomic ...

Climate sensitivity and variation in first flowering of 26 Narcissus cultivars.

The first flowering dates of 26 Narcissus cultivars were recorded over a 27-year period on the island of Guernsey, within the English Channel. We analysed flowering trends over time and relationships with climate variables. The study revealed that earlier flowering cultivars advanced most and were more variable than later flowering Narcissus. We furthermore discovered a strong relationship between flowering and climate variables, with temperature appearing to be the main driver. Whilst the first flowering date averaged over all cultivars did show a significant advance, this was significant for only one of the individual cultivars. This is likely because temperatures from December to March had not significantly increased in Guernsey during the study period (1985 to 2011).

Optimization of fragrance extraction: Daytime and flower age affect scent emission in simple and double narcissi

The fragrance of Narcissus flowers is used for luxury perfumes because of its delicate odor. Fragrance productivity is relatively low and an increase in fragrance yield is therefore an important issue. This study investigated the development of scent emission and scent profile of narcissus cultivars of simple and double flower architecture. Headspace solid-phase microextraction (HS-SPME) and capillary gas chromatography/mass spectrometry (GC–MS) were applied to analyze flower scent in dependence of daytime and flower age. The major scent compounds identified were those typical for Narcissus species, monoterpenes and benzenoids, here in form of cis-β-ocimene and benzyl acetate. The double flower cultivar, with 11 major compounds had a more complex scent profile than the simple flower cultivar with 6 major volatiles. Both cultivars showed circadian emission patterns and produced significantly less scent during the night than during the day with a reduction of 40% in double flowers and 37% in single flowers. Four-day old flowers produced 37% and 59% less volatiles in double and simple flowers compared to freshly cut flowers. Volatile composition varied among cultivars, daytime and flower age, however benzyl acetate and cis-β-ocimene continuously formed the major compounds. Compound flowers with doubled perianth structures produced double amount of scent compared to simple flowers independent of daytime. The drastic differences in volatile production depending on daytime, flower age and flower architecture should be taken into account when using narcissus flowers for the production of absolute fragrance extracts.

Dark-stored Flurprimidol Solutions Maintain Efficacy Over Many Weeks

For a number of geophytic crops, pre-plant plant growth regulator (PGR) dips or soaks are an effective method of height control. Previous research has shown that a given PGR solution may be used to dip numerous bulbs without losing efficacy. What has been unknown is whether PGR solutions maintain efficacy over multiple-week (seasonal) time scales, especially if they have previously been used to treat bulbs. To address this question, 30 mg·L−1 flurprimidol solutions were prepared 3 weeks apart and used to dip narcissus and hyacinth bulbs and then held for 4 weeks at 17 °C in darkness. These solutions (now 7 and 4 weeks old) and a freshly prepared solution were used to dip bulbs of eight hyacinth and five narcissus cultivars. After appropriate cooling, bulbs were forced in a greenhouse. Results indicate no difference in growth reduction among the 0-, 4-, or 7-week-old solutions demonstrating no loss of PGR activity over a 7-week period. In two other experiments, 2.5, 5, and 10 mg·L−1 flurprimidol solutions were exposed to 0 to 8 days of full sun (late June) and then used to dip Lilium ‘Tresor’ bulbs for 1 minute. Growth of the plants indicated loss of growth regulation activity (taller plants) as the duration of exposure to sunlight increased, suggesting substantial photolysis of the active ingredient. Together, the results suggest that flurprimidol solutions can be held in darkness at 17 °C and used for at least 7 weeks without loss of efficacy.

Pollen feeding in Balaustium murorum (Acari: Erythraeidae): visualization and behaviour

To determine whether pollen is a significant food source for Balaustium cf. murorum (tentative identification), behavioural responses to pollen feeding were examined in short-range Petri plate bioassays. Evans blue dye was used as a tracer to stain pollen after being incorporated into the gut. The results show that all active stages (larva, deutonymph and adult) ingested whole pollen from viburnum shrub (Viburnum) and daffodil (Narcissus) cultivars. All active stages fed on all types of pollen tested: tulip (Tulipa), daffodil (Narcissus), pear (Pyrus), maple (Acer), viburnum (Viburnum) and crabapple (Malus) cultivars except for tulip in the adult and tulip, pear and crabapple in the deutonymph. A higher percentage of larvae fed on pollen-covered surfaces and cleared pollen at a faster rate than other life stages in the bioassays. Clearance of viburnum and daffodil pollen by larvae and deutonymphs was particularly rapid, but this shifted to maple and crabapple pollen in the adult. In pheromone bioassays, pollen-fed larvae, deutonymphs and adults did not prompt clustering or avoidance by free-ranging mites. Our conclusion is that B. murorum can feed on pollen from different sources, no attraction-aggregation pheromone or alarm pheromone is emitted by fed mites and pollen feeding is more important for larvae that emerge in early spring when other food options are scarce.

Ethephon Substrate Drenches Inhibit Stem Extension of Floriculture Crops

Ethephon [(2-chloroethyl) phosphonic acid] is a plant growth regulator that releases ethylene on application and can abort flowers, stimulate branching, and inhibit stem elongation. Although ethephon is used as a foliar spray during the commercial production of many ornamental crops, its effectiveness as a drench has not been widely investigated. We performed experiments to quantify the effects of an ethephon drench on growth and flowering of a range of bedding plant and Narcissus cultivars and to assess the effect of lime on ethylene release from a peat substrate. A substrate drench of 0, 100, 250, or 500 mg·L−1 ethephon was applied to 12 potted Narcissus cultivars at one location, and up to 200 mg·L−1 was applied to 24 cultivars of bedding plants at three locations. Compared with untreated controls, ethephon generally reduced plant height at flowering and the effect increased with increased concentration. For example, Narcissus treated with a 250 mg·L−1 ethephon drench had stems that were 20% to 40% shorter at the end of flowering than control plants. However, ethephon drenches generally caused a 2- to 3-day flowering delay, and two cultivars had a phytotoxic response. Among the bedding plants studied, a 100-mg·L−1 ethephon drench suppressed plant height at flowering by greater than 30% in Catharanthus, Celosia, Dianthus, and Verbena, but by only 10% to 15% in Lobelia, Lycopersicon, and Tagetes. The drenches also delayed flowering in 10 of the 16 crops measured and decreased dry mass accumulation in all of the crops measured. Ethephon release from peat substrate became maximal ≈120 h after application and was dramatically increased by incorporation of dolomitic lime up to a rate of 9.5 kg lime per m3 of peat. Collectively, these studies show that ethephon substrate drenches inhibit stem elongation in a broad range of floriculture crops, but can also delay flowering and reduce biomass accumulation.

Bioactive alkaloid extracts from Narcissus broussonetii: Mass spectral studies

Plants of the Amaryllidaceae family are a well-known source of tetrahydroisoquinoline alkaloids with a wide range of biological activities, including antiviral, antitumoral, antiparasitic, psychopharmacological, and acetylcholinesterase inhibitory, among others. Recent advances in the use of GC or LC coupled to MS have allowed a chemically guided isolation of uncommon and bioactive alkaloids. In the present work, analytical methods were applied to study the alkaloid profile of Narcissus broussonetii, a plant endemic to North Africa. Using the GC-MS technique and an in-home mass fragmentation database, twenty-three alkaloids were identified, including the very rare dinitrogenous alkaloids obliquine, plicamine, and secoplicamine. Applying LC-ESI-LTQ-Orbitrap-MS, fragmentation profiles were found to be similar for obliquine and plicamine but different for secoplicamine. Pretazettine, a potent cytotoxic alkaloid, was also isolated from N. broussonetii, although its identification by GC-MS was only possible after a BSTFA-derivatization. The silylated crude methanolic extract only showed the presence of pretazettine-TMS, confirming that tazettine was formed after the alkaloid extraction. The same observation was made in Narcissus cultivars in which tazettine had been detected as the major alkaloid. As part of an ongoing project on MS of Amaryllidaceae alkaloids, the silylated tazettine and pretazettine were studied by GC-MS/MS, and found to differ in their fragmentation routes. Finally, the EtOAc extract of N. broussonetii showed notable in vitro activity against Trypanosoma cruzi, with an IC(50) value of 1.77 μg/ml.

Effect of radiation on regeneration of Chinese narcissus and analysis of genetic variation with AFLP and RAPD markers

The aim of our study was to establish an efficient in vitro propagation protocol for Chinese narcissus (Narcissus tazetta var. chinensis) to obtain variants of this species using γ-radiation treatment and evaluate the effectiveness of this system for variant induction using amplification fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) analysis. Various doses (5–100 Gy) of gamma rays were applied to investigate the effect of radiation on adventitious bud formation from bulb-scales and the survival rate of plantlets. It was demonstrated that the regeneration of Chinese narcissus was very sensitive to gamma radiation even at low doses. The survival and multiplication rate significantly decreased with an increase of radiation dose. The optimal irradiation dose for survival and mutation induction was approximately 10 Gy. The genetic variations among the regenerants derived from irradiated explants were evaluated by DNA fingerprinting using RAPD and AFLP markers which detected a variation frequency of 8.33% and 15.48% respectively. The high frequency of mutants detected by molecular markers indicated that treatment of in vitro cultures with γ-rays may be an effective way to improve narcissus cultivars.

Effect of light wavelength on growth and flowering of narcissi forced under short-day and low quantum irradiance conditions

SummaryFour narcissus cultivars were forced under artificial light using fluorescent lamps which emitted white (307 – 770 nm), blue (393 – 580 nm), red (540 – 760 nm), yellow (450 – 750 nm), or green (387 – 680 nm) light. The photosynthetic photon flux density was 12.5 μmol m–2 s–1, with a 6 h photoperiod. Light colour (wavelength) had no significant effect on flowering date, or on the number of flowers collected (P < 0.05). Narcissus bulbs exposed to blue light (393 – 580 nm) formed shorter, more rigid shoots of lower weight with 13 – 40% shorter leaves.

Narcissus bulblet formation in vitro: effects of carbohydrate type and osmolarity of the culture medium

Shoot clump cultures of Narcissus cultivars St. Keverne and Hawera were used to investigate the effects of culture medium carbon supply, type of carbohydrate and osmolarity on in vitro bulblet development. Increasing the medium osmolarity using mannitol or sorbitol, which did not act as substrates for growth, failed to stimulate bulblet formation with either cultivar. An exception to this was a relatively small increase in total bulblet dry weight per culture, in the cultivar Hawera only, caused by adding 30 g l −1 sorbitol in combination with 30 g l−1 sucrose. Simultaneously increasing the medium osmolarity and carbon supply using the metabolisable carbohydrate sources, sucrose, glucose, fructose or an equimolar mixture of glucose and fructose stimulated bulblet production, total dry matter accumulation and partitioning into bulblets. At comparable levels of carbon supply up to 19.0 g l−1, bulblet development of both cultivars was similar with monosaccharide and sucrose media. This indicates that substrate supply is more important for bulblet development than osmolarity of the culture medium. The cultivar Hawera also showed similar responses to monosaccharide and sucrose media supplying 37.9 g C l−1, despite the high osmolarity of monosaccharide media (c. 650 m Osm kg−1, equivalent to −1.6 MPa, compared to 380 m Osm kg−1 for sucrose medium). However in St. Keverne total dry matter accumulation and dry weight per bulblet were further stimulated only by increasing the sucrose supply from 19.0 to 37.9 g C l−1, not by increasing the monosaccharide supply. Implications of the findings for Narcissus micropropagation are discussed.