梅花草的组织培养和快速繁殖

1植物材料梅花草(Parnassia palustris L.). 2材料类别无菌苗. 3培养条件种子萌发采用MS基本培养基.不定芽诱导与增殖培养基:(1)MS 6-BA 1.0 mg·L-1(单位下同);(2)MS 6-BA 2.0 NAA 0.2 GA 2.0.壮苗培养基:(3)MS NAA 0.1.生根培养基:(4)1/2MS NAA 0.1.上述培养基中均附加3%蔗糖和0.6%琼脂,pH 5.8.培养温度为(24±2)℃,光照时间16 h·d-1,光强27～36 μmol·m-2·s-1.     

Influence of parental nitrogen : phosphorus stoichiometry on seed characteristics and performance of Holcus lanatus L. and Parnassia palustris L.

Plant Ecology - Nitrogen (N) and phosphorus (P) availability affect plant sexual reproduction performance. Seed as the main product of sexual reproduction is expected to be affected by N and P...     

Parnassia palustris: a genetically diverse species in Scandinavia

Patterns of variation at nine enzyme loci were examined in 528 plants representing diploid and tetraploid populations of Parnassia palustris s. l. in Europe to assess genetic variation patterns and migration history. Half of the plants showed a unique multilocus phenotype and 75% of all phenotypes occurred only in Scandinavia. Diploid populations showed similar levels of genetic diversity as other widespread outbreeding species with animal-mediated pollination and F -statistics indicated excessive heterozygosity and low rates of gene flow among them. In spite of dramatic population histories caused by the ice ages, diploid populations have maintained the same genetic diversity in Scandinavia as in central and southern Europe. Northern populations have apparently been established through the gradual advance of genetically variable populations and patterns of variation at individual loci indicate different migration routes, from the south-south-west and the east-north-east, respectively. The data strongly support a repeated autoploid origin of the tetraploid cytotype which has been much more successful than the diploid progenitors in colonizing new land since the last ice age. High genetic diversity in Scandinavia has apparently been obtained by a combination of immigration of plants from different source areas and recurrent formation of autotetraploids from diploid progenitors.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 347−372.     

Short‐term costs related to male and female structures in alpine Parnassia palustris

The aim of this study was to investigate the potential costs related to male and female structures in a small, hermaphroditic alpine plant species, Parnassia palustris L. We studied in the field the effect of experimental manipulation of seed set (female structures) as well as anthers and staminodes (male structures) on next year's survival, flowering, seed set and growth. We found no statistically significant differences between the treatments in survival, number of flowers and fruits, fruit/flower ratio, seed number or mean mass per seed the following year. Furthermore, there was no statistically significant difference in growth response between the treatments. These observations indicate both that the manipulations of the flowers the previous year had no effect on growth and that the competition between growth and sexual reproduction was negligible. Our results may reflect small investments in reproduction, abundance of soil resources and/or that all resources saved by the plant one year are not necessarily invested in reproduction or growth next year.     

Hochgradige Dysploidie beiCaltha palustris L.

Ohne Zusammenfassung     

Population structure of an endangered species living in contrasted habitats: Parnassia palustris (Saxifragaceae)

In endangered species, it is critical to analyse the level at which populations interact (i.e. dispersal) as well as the levels of inbreeding and local adaptation to set up conservation policies. These parameters were investigated in the endangered species Parnassia palustris living in contrasted habitats. We analysed population structure in 14 populations of northern France for isozymes, cpDNA markers and phenotypic traits related to fitness. Within population genetic diversity and inbreeding coefficients were not correlated to population size. Populations seem not to have undergone severe recent bottleneck. Conversely to pollen migration, seed migration seems limited at a regional scale, which could prevent colonization of new sites even if suitable habitats appear. Finally, the habitat type affects neither within-population genetic diversity nor genetic and phenotypic differentiation among populations. Thus, even if unnoticed local adaptation to habitats exists, it does not influence gene flow between populations.     

Neue teratologische Beobachtungen anParnassia palustris L.

Ohne Zusammenfassung     

Pollen Morphology of Parnassia L. （Parnassiaceae） and Its Systematic Implications

The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect.Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China,with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassiafaberi Oliv.) colpi,implying that Southwest China is the center of diversification of the genus.     

Pollen Morphology of Parnassia L. (Parnassiaceae) and Its Systematic Implications

The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type Ⅰ, with foveolate-reticulate sculpture; (ii) type Ⅱ, with a finely reticulate sculpture; and (iii) type Ⅲ, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect.Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China,with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi,implying that Southwest China is the center of diversification of the genus.     

Euploidie,Aneuploidie und B-Chromosomen beiCaltha palustris L.

Ohne ZusammenfassungMit 21 Textabbildungen.     

Ultrastructural Changes in the Petals of Senescing flowers of Dianthus caryophyllus L.

Ultrastructural changes associated with carnation petal senescencewere investigated using ethylene levels of individual petalsas a physiological monitor of the senescence process. Limitedvacuolar and cytoplasmic vesiculation was observed in pre-senescentpetals which became more extensive in pre-climacteric tissues,along with dilation of the outer mitochondrial membrane. Climactericmesophyll tissue was characterized by widespread cytolysis.Intact cells possessed a highly reduced cytoplasm and vacuoleswith electron-dense deposits. Degenerative changes became evidentin the vasculature at this stage. These included occlusion ofthe sieve plate, and membrane abnormalities in the companioncells. Post-climacteric tissue was characterized by looseningof wall fibrillar structure in the vasculature, the appearanceof intracellular cytoplasmic debns and cells completely devoidof contents. These changes are discussed in relation to developmentalregulation on the one hand, and increasing levels of membranedisorgamsation on the other, leading to a possible ‘errorcatastrophe’ and final senescence. Dianthus caryophyllus L. cv., White Sim, carnation, Petal senescence, ultrastructure, ethylene, climacteric vacuoles, membranes, wall lysis     

Development and Structure of the Root Cortex in Caltha palustris L. and Nymphaea odorata Ait.

Structural features of the mature root cortex and its apoplasticpermeability to dyes have been determined for two dicotyledonouswetland plants of differing habitats: Nymphaea odorata, growingrooted in water and mud, and Caltha palustris, growing in temporalwetlands among cattails. In mature roots, movement of the apoplasticdyes, berberine and safranin, into the roots was blocked atthe hypodermis, indicating the presence of an exodermis. A hypodermiswith an exodermis, i.e. Casparian bands in the outermost uniseriatelayer plus suberin lamellae, is present in both species. InN. odorata, hypodermal walls are further modified with cellulosicsecondary walls. Roots of N. odorata and C. palustris have anendodermis with Casparian bands only. A honeycomb aerenchymais produced by differential expansion in N. odorata and includesastrosclereids and diaphragms, while roots of C. palustris haveno aerenchyma, but some irregular lacunae are found in old roots.These aspects of cortex structure are related to an open meristemorganization, with unusual patterns of cell divisions in certainground meristem cells (called semi-regular hexagon cells) ofN. odorata. The correlation between aerenchyma pattern and hypodermalstructure appears to be related to habitat differences.Copyright2000 Annals of Botany Company Caltha palustris, Nymphaea odorata, root development, cortex, endodermis, aerenchyma, exodermis, hypodermis, permeability, wetland plants     

The Abscission of Rose Petals

Petal abscission was studied in twelve hybrid tea rose (Rosahybrida L.) cultivars. At about 20 °C the time to petalabscission in uncut stems in greenhouses was the same as incut stems placed in water in the greenhouse or in a climate-controlledroom. The time between petal unfolding and abscission dependedon the cultivar, and varied between 12 and 35 d. The time topetal abscission of the cultivars was inversely correlated withtheir flower diameter at full bloom (linear regression, r² =0·82). In the cultivars with a relatively large flowerdiameter (10-18 cm) the petals fell without visible desiccationsymptoms, whereas in the group with a small diameter the petalswere partially or fully desiccated when shed. Fertilization occurred in some flowers of a few cultivars studied.In cultivars with a relatively large flower diameter (Papa Meilland,Cocktail, Dr. Verhage, Tineke) it had no effect on the timeto abscission in Motrea, Europa, and Carolien roses, which bearsmall flowers, the petals fell after fertilization, whereasin unfertilized flowers of the latter group of cultivars anabscission zone just above the uppermost node became activeand all parts above this node (pedicel and flower) turned brownand desiccated, though remained attached for more than a month. It is concluded that in the cultivars investigated: (a) thetime to petal abscission was inversely related to their flowerdiameter, (b) abscised petals were more desiccated in cultivarsin which the time to abscission was longer, (c) fertilizationhad little effect on the time to abscission in most cultivars,whereas the absence of fertilization prevented petal abscissionin a number of the small-diameter cultivars where it was replacedby flower abscission, and (d) cutting and placement in waterat 20 °C did not affect the time to abscission.Copyright1995, 1999 Academic Press Abscission, fertilization, flowers, petals, Rosa hybrida L., rose, water stress, carbohydrate stress     

Variability and Constancy in Cellular Growth of Arabidopsis Sepals

Growth of tissues is highly reproducible; yet, growth of individual cells in a tissue is highly variable, and neighboring cells can grow at different rates. We analyzed the growth of epidermal cell lineages in the Arabidopsis (Arabidopsis thaliana) sepal to determine how the growth curves of individual cell lineages relate to one another in a developing tissue. To identify underlying growth trends, we developed a continuous displacement field to predict spatially averaged growth rates. We showed that this displacement field accurately describes the growth of sepal cell lineages and reveals underlying trends within the variability of in vivo cellular growth. We found that the tissue, individual cell lineages, and cell walls all exhibit growth rates that are initially low, accelerate to a maximum, and decrease again. Accordingly, these growth curves can be represented by sigmoid functions. We examined the relationships among the cell lineage growth curves and surprisingly found that all lineages reach the same maximum growth rate relative to their size. However, the cell lineages are not synchronized; each cell lineage reaches this same maximum relative growth rate but at different times. The heterogeneity in observed growth results from shifting the same underlying sigmoid curve in time and scaling by size. Thus, despite the variability in growth observed in our study and others, individual cell lineages in the developing sepal follow similarly shaped growth curves.Cells undergo multiple rounds of growth and division to create reproducible tissues. In some plant tissues, such as expanding cotyledons, reproducibility can occur on a cellular level during specific intervals of development, where cotyledon cells exhibit uniform cellular growth (Zhang et al., 2011). However, several studies on cell division and growth in other developing plant tissues have demonstrated that plant cells exhibit considerable cell-to-cell variability during development (Meyer and Roeder, 2014). For example, in both the Arabidopsis (Arabidopsis thaliana) meristem and leaf epidermis, cells show spatiotemporal variation in individual cell growth rates (GRs; Asl et al., 2011; Elsner et al., 2012; Kierzkowski et al., 2012; Uyttewaal et al., 2012). Furthermore, cell divisions have been observed with marked randomness in their timing and orientation (Roeder et al., 2010; Besson and Dumais, 2011; Roeder, 2012). In this study, we identify a hidden, underlying pattern in the seemingly random GR (Box 1) of cells during the formation of sepals in Arabidopsis.Open in a separate windowBox 1.Definitions of GR terms. (For details on the calculations, see “Materials and Methods.”)Plant cell growth is defined as an increase in cell size due to an irreversible expansion of the cell wall. Neighboring cells physically accommodate one another during plant growth because their cell walls are glued together with a pectin-rich middle lamella, which prevents cell mobility. The cell wall is a thin, stiff layer composed of a polymer matrix including cellulose, hemicellulose, and pectin (Somerville et al., 2004; Cosgrove, 2005). Plant cells change their size and shape by modifying their turgor pressure and/or the mechanical properties of their walls, such as elasticity, plasticity, and extensibility. Growing plant cells exert forces on their neighbors through their walls, and cell wall stresses created by these forces feed back to alter the growth anisotropy (Hamant et al., 2008; Sampathkumar et al., 2014). Although these feedbacks can coordinate growth, they may also amplify differences in growth between neighboring cells (Uyttewaal et al., 2012).Two competing computational models have proposed explanations of the cellular heterogeneity observed in growing tissues by making different assumptions about how cells grow. In the first, it is assumed that relative growth rates (RGRs) of all cells are uniform in space and time, whereas variation in the timing of division causes the heterogeneity of cell sizes (Roeder et al., 2010). This model suggests that cell divisions cut the sepal into semiindependent cells, which grow uniformly within the expanding organ (Kaplan and Hagemann, 1991). The second model postulates the reverse process: timing of cell division is uniform, but cellular growth is variable and depends on the size of the cell (Asl et al., 2011). This model suggests that cells are autonomous. Currently, there is biological evidence for both models. Variability in cell division timing is observed in sepals and meristems, whereas variability in cellular GRs has been observed in leaves and meristem cells (Reddy et al., 2004; Roeder et al., 2010; Asl et al., 2011; Elsner et al., 2012; Kierzkowski et al., 2012; Uyttewaal et al., 2012). Thus, the debate on how the growth of individual cells within an organ relates to one another remains unresolved.The identification of underlying patterns in noisy cellular growth processes is challenging. Technical difficulties include the capability for cellular-resolution imaging of the tissue at sufficiently small time intervals. Previous studies (Zhang et al., 2011; Elsner et al., 2012; Kierzkowski et al., 2012) did not image and track individual cells, or they had a coarse time resolution, with 11- to 48-h intervals between images, which may have hidden important temporal dynamics. We studied growing cells in the Arabidopsis sepal, which allows for live imaging with cellular resolution at 6-h intervals (Roeder et al., 2010). The sepal is the leaf-like outermost floral organ of Arabidopsis (Fig. 1) with four sepals of stereotypical size produced per flower. Its accessibility for live imaging makes the sepal an excellent system for studying organogenesis (Roeder et al., 2010, 2011, 2012; Qu et al., 2014). Sepals exhibit high cellular variability in the timing of division and endoreduplication, an alternative cell cycle in which a cell replicates its DNA but fails to divide (Roeder et al., 2010). Furthermore, quantifying cell growth in sepals may shed light on growth mechanisms of other plant organs, such as leaves (Poethig and Sussex, 1985; Roeder et al., 2010).Open in a separate windowFigure 1.Diverse sizes of Arabidopsis sepal cells. A, Four sepals (s) are the outermost green leaf-like floral organs in Arabidopsis. B and C, Scanning electron micrographs of a mature Arabidopsis sepal show that the outer epidermal cells have a wide range of sizes. Asterisks mark some of the largest cells (giant cells) that can span 1/4 the length of the sepal. Scale = 100 µm.Another key challenge in analyzing cellular growth is the identification of trends in noisy data. Inaccuracies in data acquisition, such as segmentation errors, and noisy growth of individual cells can hide meaningful spatiotemporal trends in growth. GRs measured over longer time intervals will have reduced noise, but they may also obscure important temporal dynamics. Alternatively, previous studies have examined growth of the whole organ or its subregions to avoid cellular noise (De Veylder et al., 2001; Mündermann et al., 2005; Rolland-Lagan et al., 2005, 2014; Kuchen et al., 2012; Remmler and Rolland-Lagan, 2012). However, precise cellular patterns are not resolved. In our study, we use cellular resolution data to define spatially averaged kinematics while keeping the full temporal resolution to identify course-grained spatial trends in the dynamics of cellular growth (Box 1).We analyze the relationships among the growth of individual cell lineages in a developing Arabidopsis sepal by live imaging and computational analyses. We have developed continuous low-order displacement fields to represent the spatially averaged kinematics of the sepal (Box 1). We find that the growth of the tissue surface area, cell lineage area, and wall length follows S curves, suggesting that their GRs vary over time. Additionally, we find that there is a linear correlation between the maximum GR (i.e. size increase per hour) and the size of the cell. We furthermore find that each sepal cell lineage reaches the same maximum RGR (i.e. GR divided by size). However, each cell reaches the maximum RGR at a different time during its development, generating the observed heterogeneity. Thus, we find underlying similarities in the growth curves of sepal cells.