A phenological scale for the development of Gladiolus

A staging system for development of gladiola (Gladiolus × grandiflorus) that relies on simple, visual, non‐destructive criteria is proposed. Four field trials were conducted during the spring 2010, autumn/winter 2011 and winter 2011 at Santa Maria, RS, Brazil, with different gladiola cultivars, in order to observe the developmental stages of the above‐ground parts and their dry matter. The developmental cycle, which starts at dormant corm and ends with plant senescence, is divided into four developmental phases: dormancy phase, sprouting phase (from filiform roots appearance to sheaths appearance), vegetative phase (from emergence of the first leaf tip to emergence of the final leaf tip on the stem) and reproductive phase (from heading to plant senescence). The developmental stages that were identified during the dormancy phase and during the sprouting phases are coded as S stages: S0 = dormant corm, S1 = appearance of roots, S2.1 = first sheath, S2.2 = second sheath and S2.3 = third sheath. Vegetative phase is coded as V stages: VE = emergence of the sheaths above ground, V1 = first leaf, V2 = second leaf, Vn = nth leaf and VF = flag leaf. Leaf tip is the marker for V1–VF. The developmental stages during the reproductive phases are coded as R stages: R1 = heading, R2 = blooming, R3 = onset of flowering, R4 = end of anthesis, R5 = end of florets senescence and R6 = plant senescence (leaves and floret axis are brown). Sub‐stages have also been assigned between R1 and R2 and between R3 and R4. Illustrations (photographs) of each developmental stage taken from field pot‐grown plants are provided and the proposed scale was tested with field observations. These criteria are straight forward and allow for quick determination of development stage. This system can be used by both farmers and for experimental trials.     

Ecological Risk Assessment and Regulation for Genetically-Modified Ornamental Plants

Classic plant breeding has increased the beauty and utility of ornamental plants, but biotechnology can offer completely new traits for plants used in homes and gardens. The creation of blue petal color in carnations and roses are examples where biotechnology has created novelty that conventional hybridization cannot match. However, all innovations have benefits and risks, and future commercialization of transgenic ornamental plants raises complex questions about potential negative impacts to managed landscapes and natural ecosystems. Predictive ecological risk assessment is a process that uses current knowledge to estimate future environmental harms or benefits arising from direct or indirect exposure to a genetically-modified (GM) plant, its genes, or gene products. This article considers GM ornamental plants in the context of current ecological risk assessment principles, research results, and current regulatory frameworks. The use of ecological risk assessment by government agencies to support decision-making is reviewed in the context of ornamental plants. Government risk assessments have usually emphasized the potential for pollen-mediated gene flow, weediness in managed areas, invasion of natural areas, and direct harm to nontarget organisms. Some of the major challenges for predictive risk assessment include characterizing gene flow over time and space, plant fitness in changing environments, and impacts to nontarget organisms, communities and ecosystems. The lack of baseline information about the ecology and biodiversity of urban areas, gardens, and natural ecosystems limits the ability to predict potential hazards, identify exposure pathways, and design hypothesis-driven research. The legacy of introduced ornamental plants as invasive species generates special concern about future invasions, especially for GM plants that exhibit increased stress tolerance or adaptability. While ecological risk assessments are a valuable tool and have helped harmonize regulation of GM plants, they do not define the acceptable level of risk or uncertainty. That responsibility belongs to regulators, stakeholders and citizens.     

Genetic Modification in Floriculture

An important driving force for the floriculture industry is the development of novel plants and flowers. New varieties provide marketing opportunities for retailers and judicious selection can increase productivity for growers, as well as improving the quality of the final product in the consumer's hands. While plant exploration and conventional breeding programs have been very successful in achieving these goals, genetic modification offers additional routes for the generation of new varieties of important floricultural plants. This can be achieved by the incorporation of genes from outside of the normally available gene pool. This paper provides a summary of the potential applications of gene technology in floriculture and reviews progress to date, with a particular emphasis on the manipulation of flower color. The manipulation of the anthocyanin biosynthesis pathway in carnation to produce novel-colored flowers is so far the only commercial application of genetic modification in floriculture. This progress is in stark contrast to the widespread cultivation of genetically modified broad-acre crops. The commercial use of gene technology requires adherence to regulatory regimes specific to genetically modified plants, and compliance with intellectual property laws. These added complexities are a significant cost, which may be hampering the use of gene technology by breeders of floricultural crops. Another factor may be a perception that the public and retail trade may not accept genetically modified floricultural products. Experience in the real marketplace with the Florigene Moon-series? of genetically modified carnation suggests that these concerns are unwarranted.     

Stable transformation of petunia plastids

Plastid transformation results in stably expressed foreign genes, which for most Angiosperms are largely excluded from sperm cells, thereby greatly reducing the risk of foreign gene spread through pollen. Prior to this work, fertile plastid transformants were restricted to tobacco, tomato and Lesquerella . Application of plastid engineering in the important floriculture industry requires the development of stable plastid transformation in a major ornamental plant species such as Petunia hybrida. Here we describe the successful isolation of fertile and stable plastid transformants in a commercial cultivar of P. hybrida (var. Pink Wave). Plastid targeting regions from tobacco were used to integrate aad A and gusA between the acc D and rbc L genes of P. hybrida plastid DNA following particle bombardment of leaves. For three spectinomycin and streptomycin resistant lines, DNA blot analysis confirmed transgene integration into plastid DNA and homoplasmy. Maternal inheritance and homoplasmy resulted in 100 transmission of spectinomycin resistance to progeny after selfing. Plastid transformants expressed the gusA gene uniformly within leaves and to comparable levels in all three lines. Insertion of trait genes in place of gusA coding sequences enables immediate applications of our plastid transformation vector. Establishment of plastid transformation in P. hybrida facilitates a safe and reliable use of this important ornamental plant for research and plant biotechnology.These two authors contributed equally to this work.     

Practical placement improves the performance of slow release sachets of Neoseiulus cucumeris

This research investigated factors that affect the performance of Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) slow release sachets, focusing on dispersal in environments with non-continuous canopies and high exposure to greenhouse environmental conditions. When released from a central plant in a tray, the distribution of N. cucumeris across all other plants was uneven with the majority of mites recovered at the release point. Shading by a plant canopy reduced the mean internal temperature of the sachets, temperature peaks were less pronounced and the relative humidity was higher than in exposed sachets. Most N. cucumeris left the exposed sachets in the first week, followed by reduced emergence and no signs of breeding were observed in the sachets. Sachets in a plant canopy had low emergence during the first week, increasing thereafter. Overall, plant canopy sachets released more N. cucumeris than exposed sachets. Emergence patterns of N. cucumeris from sachets under greenhouse and ideal conditions were variable, with sachets generally performing better under ideal conditions. Even under constant ideal conditions, the number of N. cucumeris released from sachets varied among batches and some produced a suboptimal number of predators. Results demonstrate that exposed greenhouse conditions can seriously affect the performance of N. cucumeris sachets and that good coverage is needed to compensate for limited dispersal in non-continuous plant canopies.     

外来入侵害虫——西花蓟马在山东省不同地区主要花卉上的分布

【背景】外来入侵害虫西花蓟马于2003年首次在北京郊区被发现,并逐渐扩散蔓延,目前已在我国局部地区暴发成灾。【方法】于2008～2009年通过定点调查的方法对山东省115个地区258个样点的主要花卉上的蓟马种类进行了分析。【结果】山东省主要花卉上发生的蓟马有11种,包括花蓟马、黄胸蓟马、黄蓟马、西花蓟马、棕榈蓟马、烟蓟马、禾花蓟马、横纹蓟马、腹小头蓟马、黑白纹蓟马、油加律带蓟马等,其优势种为花蓟马。外来入侵害虫西花蓟马在山东省18个地区的花卉上被发现。其中,荣成市区发生最重,占蓟马采集总量的51.86%;德州市区和青岛市区发生次之,分别占蓟马采集总量的34.21%和33.88%;其他地区西花蓟马发生量占采集总量的1.39%～18.75%。【结论与意义】西花蓟马已在山东省定殖并广泛分布,相关部门应做好西花蓟马的预防与控制工作。     

外来人侵害虫——西花蓟马在山东省不同地区主要花卉上的分布

【背景】外来入侵害虫西花蓟马于2003年首次在北京郊区被发现,并逐渐扩散蔓延,目前已在我国局部地区暴发成灾。【方法】于2008～2009年通过定点调查的方法对山东省115个地区258个样点的主要花卉上的蓟马种类进行了分析。【结果】山东省主要花卉上发生的蓟马有11种,包括花蓟马、黄胸蓟马、黄蓟马、西花蓟马、棕榈蓟马、烟蓟马、禾花蓟马、横纹蓟马、腹小头蓟马、黑白纹蓟马、油加律带蓟马等,其优势种为花蓟马。外来入侵害虫西花蓟马在山东省18个地区的花卉上被发现。其中,荣成市区发生最重,占蓟马采集总量的51．86％;德州市区和青岛市区发生次之,分别占蓟马采集总量的34．21％和33．88％;其他地区西花蓟马发生量占采集总量的1．39％～18．75％。【结论与意义】西花蓟马已在山东省定殖并广泛分布,相关部门应做好西花蓟马的预防与控制工作。     

Efficient TDZ-induced regeneration from capitulum explants of Gerbera jamesonii Bolus ex Hooker F. - an ornamental plant with high aesthetic value

Gerbera jamesonii Bolus ex Hooker F. (Asteraceae), a most prominent ornamental plant ranking fifth in the world cut flower market has gained huge demand across the globe for its high aesthetic value. In the present study, an efficient plant regeneration protocol was developed using capitulum explants from the field grown mature plants of G. jamesonii. A successful surface sterilization procedure was established using a series of sterilants without affecting explant regenerability. The culture of capitulum explants on Pre-culture Induction Medium [(PIM), Murashige and Skoog (MS) medium fortified with 0.5?mg/L thidiazuron (TDZ) in combination with low levels of auxins] for a period of 2 weeks in dark conditions was crucial for inducing morphogenetic response. Upon transfer onto Shoot Regeneration Medium [(SRM), MS +4.0?mg/L 6-benzyladenine (BA) and 0.2?mg/L NAA], explants has significantly produced highest number of shoots (16?±?0.33). Incubation for 18–21?days on Shoot Multiplication and Elongation Medium [(SMEM), MS +2.0?mg/L BA +0.2?mg/L NAA] resulted in the highest number of multiple shoots (22.00?±?0.93) with increased mean shoot length (3.49?±?0.08). In vitro elongated shoots were rooted (95%) on ½ MS +1.0?mg/L indole-3-acetic acid (IAA) within 10–12?days and fully rooted plants were transferred to poly-house for hardening with 90% survival rate.     

Effects of midas® on nematodes in commercial floriculture production in Florida

Cut flower producers currently have limited options for nematode control. Four field trials were conducted in 2006 and 2007 to evaluate Midas® (iodomethane:chloropicrin 50:50) for control of root-knot nematodes (Meloidogyne arenaria) on Celosia argentea var. cristata in a commercial floriculture production field in southeastern Florida. Midas (224 kg/ha) was compared to methyl bromide:chloropicrin (98:2, 224 kg/ha), and an untreated control. Treatments were evaluated for effects on Meloidogyne arenaria J2 and free-living nematodes in soil through each season, and roots at the end of each season. Plant growth and root disease were also assessed. Population levels of nematodes isolated from soil were highly variable in all trials early in the season, and generally rebounded by harvest, sometimes to higher levels in fumigant treatments than in the untreated control. Although population levels of nematodes in soil were not significantly reduced during the growing season, nematodes in roots and galling at the end of the season were consistently reduced with both methyl bromide and Midas compared to the untreated control. Symptoms of phytotoxicity were observed in Midas treatments during the first year and were attributed to Fe toxicity. Fertilization was adjusted during the second year to investigate potential fumigant/fertilizer interactions. Interactions occurred at the end of the fourth trial between methyl bromide and fertilizers with respect to root-knot nematode J2 isolated from roots and galling. Fewer J2 were isolated from roots treated with a higher level of Fe (3.05%) in the form of Fe sucrate, and galling was reduced in methyl bromide treated plots treated with this fertilizer compared to Fe EDTA. Reduced galling was also seen with Midas in Fe sucrate fertilized plots compared to Fe EDTA. This research demonstrates the difficulty of reducing high root-knot nematode population levels in soil in subtropical conditions in production fields that have been repeatedly fumigated. Although soil population density may remain stable, root population density and disease can be reduced.     

花文化教育在《花卉学》教学中的功能

花文化是在漫长的人类历史发展过程中形成的一系列与花卉相关的文化现象和文化信息的总和。概述了以花卉著作、花卉文学、花画、花语、花卉食品以及花疗等为表现形式的花文化的内涵,论述了花文化教育在《花卉学》教学中的功能。