Non-flowering Shoots Research Articles

The Genus Moenchia (Caryophyllaceae) in Turkey

A new identification key, full descriptions, and distribution records based on various herbaria of Turkish Moenchia are given in this study. Detailed and comparative descriptions of the studied species have been prepared. Also, a new species, Moenchia akmanii M.Keskin sp. nov., is described as for science. The new species is morphologically similar to M. graeca that is but differs by long stems, different leaves, non-flowering shoots, 3-nerved sepals, mauve anthers, etc. The new identification key has been created to distinguish taxa distributed in Turkey.

Linaria yusufeliensis, a replacement name for the Turkish Linaria turcica Makbul & Hamzaoğlu (Plantaginaceae)

Linaria Miller (1754: without page) is currently included in the Plantaginaceae family. This genus consists of ca. 150 species mainly distributed in Europe, Northern Africa and Central and Western Asia, but introduced and naturalized in other regions of the world with temperate climate (Sáez & Bernal 2009). It comprises annual or perennial herbs, with flowering and non-flowering shoots. The flowers occur in bracteate racemes and have a zygomorphic corolla with a long spur, and the lower petal closing the corolla throat; winged or wingless seeds are produced in their pods (Rocio et al. 1999).

Flowering Patterns of Understory Herbs 30 Years after Disturbance of Subalpine Old-Growth Forests by Tephra from Mount St. Helens

Premise of research. We sought to determine the role of flowering in recovery of understory herbs from a major disturbance and to determine the effects of plant and environmental factors on flowering patterns.Methodology. We counted flowering and nonflowering shoots in permanent plots eight to 10 times over a 30-year period for all 48 understory herb species in four subalpine old-growth conifer forests that received tephra (aerially transported volcanic ejecta) from the 1980 eruptions of Mount St. Helens, Washington. We defined two measures of flowering and related them to environmental and plant characteristics.Pivotal results. Patterns of flowering varied widely among species both among and within growth forms. Flowering increased with time, especially where it was initially low (for evergreen clonal plants, species that also grow in early seral habitats, and plants in deep tephra and from herb-poor sites). Some significant differences that occurred during the first 20 years disappeared by year 30. Percent of shoots flowering declined as shoot density increased, but the significance of this relationship declined until it became nonsignificant by year 25. There was a significant but weak relationship between the proportion of shoots flowering for a species and its proportional increase in shoot numbers during the 30 years of vegetation redevelopment; some species expanded populations only by flowering, while others became dominant while flowering little.Conclusions. Flowering patterns changed with time; this constitutes an important aspect of successional change. Studies of flowering and other aspects of sexual reproduction are important for understanding mechanisms of succession.

DEVELOPING INFLORESCENCES OF PROTEA 'CARNIVAL' REDUCE THE RESPONSIVENESS OF NON-FLOWERING SHOOTS TO BENZYLADENINE INDUCTION OF FLOWERS "OUT OF SEASON"

ISHS XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on Advances in Ornamentals, Landscape and Urban Horticulture DEVELOPING INFLORESCENCES OF PROTEA 'CARNIVAL' REDUCE THE RESPONSIVENESS OF NON-FLOWERING SHOOTS TO BENZYLADENINE INDUCTION OF FLOWERS OUT OF SEASON

Modeling growth dynamics of Typha domingensis (Pers.) Poir. ex Steud. in Lake Burullus, Egypt

Southern Cattail (Typha domingensis) occurs everywhere in ditches and marshy places in Egypt and is one of the major components of vegetation stands along the shores of Lake Burullus close to the Deltaic Mediterranean coast. In our study, we applied a published Typha model to describe the growth production among the various organs of Southern Cattail in Lake Burullus, one of the Mediterranean eutrophic lakes, in order to answer the following questions: (1) Is the Typha model, originally designed for T. angustifolia and T. latifolia, suited to simulate the growth of Southern Cattail in the south Mediterranean region? and (2) How is biomass production of Southern Cattail distributed among the various plant organs? Above- and below-ground biomass of Southern Cattail was sampled monthly from February 2010 to October 2010 at three sites of Lake Burullus using three randomly distributed quadrats (each of 0.5m×0.5m) at each sampling site. Shoots started to grow in February, reached the maximum biomass of 6327±441gDWm−2 in July, and then rapidly decreased in the fall when they went to senescence stage, thereafter their growth ceased before fully dying off in the winter. The total below-ground biomass reduced to 941±152gDWm−2 in March due to the upward translocation for the initial growth of shoots, gradually increased to a maximum biomass of 2184±366gDWm−2 in July by downward translocation from shoots, then decreased afterwards in the winter to reach 1193±64gDWm−2 in October. Southern Cattail allocated approximately 52% of its total biomass to non-flowering shoots, 19% to flowering shoots, 22.5% to rhizomes and 6.5% to roots. The total above-ground biomass was 2.6 times that of the total below-ground biomass. General trends for above-ground biomass, such as the slow initial growth rate followed by a high growth rate, the timing of peak biomass, and the decline of biomass due to senescence, were successfully reproduced by the model. Many characteristics typical for the below-ground biomass, such as the reduction of rhizome biomass during the early growing season, and the increase in the rhizome biomass during the later period of the season, because of the translocation of materials from current photosynthesis and shoot dry matter, were also reproduced. In general, there was good agreement between the calculated results and field data although simulated results were slightly different from observations for below-ground biomass. Respiration of the above- and below-ground organs consumes a considerable amount of net photosynthetic materials 39% and 7%, respectively. The upward translocation of rhizome resources to form new shoots in February showed 8% to the gross production and the downward translocation afterwards showed a 22% to the gross production. In conclusion, Typha model is well-suited to simulate the growth of Southern Cattail stands in the south Mediterranean region and could be used in wetland management activities to predict the potential growth of Southern Cattail in Egyptian wetlands.

Can developing inflorescences of Protea cv. Carnival reduce the responsiveness of non-flowering shoots to benzyladenine induction of flowers ‘out of season’?

Can developing inflorescences of Protea cv. Carnival reduce the responsiveness of non-flowering shoots to benzyladenine induction of flowers ‘out of season’?

Endophytic and epiphytic phyllosphere fungi of red-osier dogwood (Cornus stolonifera) in British Columbia

Endophytic and epiphytic phyllosphere fungi associated with red-osier dogwood (Cornus stolonifera), a deciduous shrub, were examined in coastal British Columbia, Canada. Current-year shoots were divided into four types based on the absence or presence of inflorescence and secondary elongated shoots at the apex of primary shoots. Leaves on these shoots were then classified into six categories so as to examine the effect of flowering, secondary shoot elongation, and shoot order within currentyear shoots on the occurrence of phyllosphere fungi. Species composition of fungi was markedly different between the interior and surface of leaves, whereas it was relatively similar among the six leaf categories in the interior or on the surface. Frequencies of the eight major species were not different between leaves on flowering and nonflowering shoots. The frequency of Colletotrichum gloeosporioides in the leaf interior was greater on leaves on the primary shoots that elongated the secondary shoots than on those that did not, and was greater on leaves on the primary shoots than on those on the secondary shoots. On the other hand, secondary shoot elongation and shoot order had no effect on the frequencies of C. gloeosporioides and the other seven epiphytes on leaf surfaces.

Endophytic and epiphytic phyllosphere fungi of red-osier dogwood (<i>Cornus stolonifera</i>) in British Columbia

Endophytic and epiphytic phyllosphere fungi associated with red-osier dogwood (Cornus stolonifera), a deciduous shrub, were examined in coastal British Columbia, Canada. Current-year shoots were divided into four types based on the absence or presence of inflorescence and secondary elongated shoots at the apex of primary shoots. Leaves on these shoots were then classified into six categories so as to examine the effect of flowering, secondary shoot elongation, and shoot order within current year shoots on the occurrence of phyllosphere fungi. Species composition of fungi was markedly different between the interior and surface of leaves, whereas it was relatively similar among the six leaf categories in the interior or on the surface. Frequencies of the eight major species were not different between leaves on flowering and nonflowering shoots. The frequency of Colletotrichum gloeosporioides in the leaf interior was greater on leaves on the primary shoots that elongated the secondary shoots than on those that did not, and was greater on leaves on the primary shoots than on those on the secondary shoots. On the other hand, secondary shoot elongation and shoot order had no effect on the frequencies of C. gloeosporioides and the other seven epiphytes on leaf surfaces.

Consequences of the Elimination of Old Leaves upon Spring Phenological Events and the New Leaves Nutrient Concentration in a Wintergreen Woody Species in the Southern Hemisphere

Previous studies analyzed the importance of old leaves conservancy for wintergreen species plant growth only after early spring old leaves elimination. However, carbon and nutrient resources for growth could have already been translocated from old leaves to shoots during autumn. In this work, the effect of old leaves absence on the leaf mass per area (LMA, g m 2 ) and nutrient concentration of new spring leaves, shoot growth, and flowering was studied in Aristotelia chilensis, an Andean Patagonic woody wintergreen species of Argentina. Plants were studied after autumn defoliation (AD) or late winter defoliation (WD) and results were compared to those of undamaged control plants (CO). The new leaves LMA and mineral nutrient (N, P, K, and Mg) concentration values did not decrease in AD or WD compared to CO plants. Conversely, CO plants showed higher flowering intensity and shoot lengthening compared to AD or WD plants. There were not remarkable differences regarding the defoliation time, though non-flowering shoots grew in a lesser degree than the flowering shoots in WD plants. It was concluded that A. chilensis old leaves cohort is an important source to shoot growth and flowering but their absence does not affect the new leaves structure or nutritional status from early spring in either AD or in WD plants. New leaves formation probably is guaranteed by resources (carbon and nutrients) previously stored in stems or even in the buds containing the preformed leaves since March, by the end of summer. Provided the availability of complete resources for the new leaf flush independently of the old leaves A. chilensis would restore the carbon balance as soon as possible to resume the growth of heterotrophic tissues at normal rates. Endogenous response to counterbalance the old leaves absence on non-flowering shoots was more effective when there was greater lag time between defoliation and shoot growth resume. Flowering and non-flowering shoots compete for the available resources when A. chilensis have not yet expanded leaves and shoots supporting reproductive structures were stronger sinks compared to non-flowering shoots in WD plants.

Management of below-ground biomass of Typha angustifolia by harvesting shoots above the water surface on different summer days

A dynamic model of regrowth in Typha angustifolia after cutting shoots above the water surface was formulated by characterizing the phenology and mobilization of resources from below-ground to above-ground organs after the cutting. The model parameters were determined by two cutting experiments to investigate the different strategies with flowering and non-flowering shoots after cutting in 2001 and by four cutting experiments to elucidate the regrowth characteristics after cutting on different days from June to September in 2002. A difference was evident both for flowering and non-flowering shoots and for each cutting day. From June to August, non-flowering shoots regrew immediately after cutting, but flowering shoots did not. The shoot regrowth height, number of leaves and shoot biomass were higher with the earlier cutting. The model was validated using the below-ground biomass observed in December 2002 and below-ground dynamics observed in 2003. In the low-flowering shoot zone of the stands, in which the percentage of flowering shoots was small (around 10%), the decrease in below-ground biomass became larger from June (20%) to August (60%). Cutting the high-flowering shoot zone (flowering shoots: 78%) in July 2001, just 1 week after peduncle formation, decreased the below-ground biomass by about 50%. In the low-flowering shoot zone, cutting just before senescence is better for decreasing below-ground biomass with a smaller rate of flowering shoots. The difference of below-ground biomass reduction in non-flowering shoots is mainly due to the decrease in downward translocation (DWT) of above-ground material to below-ground organs during senescence, because of the decrease in regrowth biomass. As for flowering shoots, the decrease in the photosynthate transportation from above-ground to below-ground organs and that of DWT are closely related because they cannot grow again within the season.

C, N, P concentrations and requirements of flowering Posidonia oceanica

The carbon, nitrogen and phosphorus contents in flowering and nonflowering shoots were compared after an important flowering event occurred in the Posidonia meadow of the Bay of Calvi. The flower formation caused a significant increase of C and a significant decrease of N concentrations in intermediate and adult leaves. Minimum daily requirements in mgshoot-1day-1 of 3.4 and 4.8 of C, 0.09 and 0.09 N, 0.01 and 0.02 of P respectively for nonflowering and flowering shoots were calculated. It shows that additional quantities of C and P are required for the inflorescence elaboration. The unchanged quantity of N required by the shoot for the inflorescence elaboration and the significant modification of N concentration in intermediate and adult leaves suggests that N is limited in the environment and that an efficient resorption of N occurs from leaves to ensure the inflorescence formation.

Anthesis effects on Posidonia oceanica (L.) Delile phenology in the Bay of Calvi (Corsica, Mediterranean Sea)

In Posidonia oceanica (L.) Delile, anthesis induces a decrease in the number of juvenile leaves resulting in a significant reduction in the number of leaves on the flowering shoots. All the leaves of the flowering shoots are narrower than the leaves of nonflowering shoots. A modification of the leaf growth also appears in flowering shoots: the oldest leaves are longer and the leaves induced during or after anthesis are shorter. At 10 m depth, in the Bay of Calvi, anthesis lasts roughly 3 months and the flowering is induced 7 months before anthesis.

156 Effects of the Inductive Period, Shoot Density, and Leaf Removal on the Flowering of Heliconia rostrata Ruiz & Pavon

Heliconia rostrata is a herbaceous-musoid sympodial rhizomatous plant that grows as clump. After three leaves are produced, each shoot of the clump may bear an inflorescence if it is induced by short days (SD). However, the relationship between shoot density and flowering has not been quantified. To evaluate the effects of the inductive period, number of shoots, and leaf removal on flowering, rhizomes were planted in 120 pots (8 L). One-third of the pots were planted with two rhizomes, while the remainder was planted with one. One-half of the pots with one rhizome were allowed to develop all their shoots for three generations, while in the remaining pots only one shoot per generation was allowed to grow. In addition, one-half of the plants in all the treatments were subjected to selective leaf removal. The plants were grown under long days (LD) >13 h in a glasshouse until four leaves were produced. Inductive SD was supplied to all the plants from 5:00 pm to 8:00 am. After 8 weeks of SD, one-half of the plants were given LD, while the other half continued under SD (conSD) until flowering. The highest percentage of flowering shoots (39% to 35%) was observed in plants under conSD; plants under SD-LD were 10% to 9%. The second generation of shoots showed the highest flowering (74% conSD and 21% SD-LD), followed by the first (62% conSD and 18% SD-LD), and third (31% conSD and 0% SD-LD) generations. Non-flowering shoots of the first generation were aborted or dead. Shoots of the third were still vegetative, since they had few leaves to be induced. Fewer flowers occurred in clumps allowed to develop all their shoots. Intact plants from rhizomes with one shoot per generation flowered more than the partially defoliated ones under conSD.

Productivity of three rose cultivars ( Rosa hybrida) trained in a ‘vase-shaped’ form and grown in a commercial glasshouse in a Mediterranean environment

A survey was conducted over 12 months to determine productivity and compare the relationships between the different shoot types of three rose cultivars of different ages. The plants were trained in a ‘vase-shaped’ architecture. Data were collected on 1 year-old ‘Sonia’, 8 year-old ‘Gabrielle’ and 7 year-old ‘Kardinal’. The ratio of basal shoots : branches : shoots (flowering and non-flowering shoots) over one season was 1 : 2 : 7 (Sonia), 1 : 3 : 8 (Gabrielle) and 1 : 3 : 11 (Kardinal). Of the shoots produced, 44% (Sonia), 29% (Gabrielle) and 19% (Kardinal) were marketable stems and the remainder were either unmarketable (discarded after harvest) or blind shoots (not harvested). A high number of unmarketable stems occurred in summer and were associated with high temperatures and the marketing requirement to harvest the entire crop over 2–3 days. The majority of blind shoots were <5 cm long and formed on the upper half of shoots or branches and in the upper half of the leaf-canopy. Although harvested stem production was positively correlated with the number of branches, increasing branch numbers does not necessarily increase the number of harvested stems in direct proportion. This has implications for plant management and harvesting techniques.

Lychnis Viscaria L. (Viscaria Vulgaris Bernh.)

Subgenus Viscaria. A tufted winter-green perennial herb. Roots of two types, white, dense fibrous below stock and longer, thick, white adventitious. Stock, woody and supporting short, erect branches, ending in mostly very short densely leafy nonflowering shoots but sometimes longer up to 50 mm, with leaves crowded on top of first node. The flowering stem is 15-60 cm, erect, hollow, dark green, becoming purple and viscid under the nodes, glabrous or slightly hairy above. Cauline leaves 50-130mm x 4-10mm, oblong to linear-lanceolate to linear-spathulate, acuminate, entire, with woolly margins at the base, otherwise glabrous, narrowing below into a long stalk-like base which widens to join the stem, becoming purple. The inflorescence is an interrupted spike-like panicle of axillary, opposite dichasia with 3-6 flowers per cyme, becoming increasingly dense towards the apex. Bracts 3-35mm long, broadly lanceolate, acuminate, glabrous, decussate, clasping around the stem. Flowers 3-50, corolla 15-20mm, pedicels 3-5 mm. Calyx 615 mm, cylindrical-clavate, membranous, purplish, glabrous, 10 -ribbed with short ovate teeth. Five petals bright purple-red, pink, rarely white, entire or emarginate, with two conspicuous coronal scales 2-4 mm long at the base, claw narrow. Styles 5. Stigmas 5, feathery. Fruit 8-11 mm long, capsule ovoid, bursting the calyx, 5-8 celled, opening by 5(-8) recurved teeth, borne on a gynophore at least half as long as the ripe capsule. Seeds 0.4-0.7mm, reniform, black, with acute tubercles, borne on cells in radially and concentrically orientated rows. Seed weight 0.074 + 0.0029 mg.

Factors limiting the distribution of Acyrthosiphon svalbardicum (Hemiptera: Aphididae) on Spitsbergen

The distribution of the high arctic aphid Acyrthosiphon svalbardicum was found to have a distinct limit in the Kongsfjorden area of Spitsbergen; the probability of site occupancy increased with distance from the fjord mouth and decreased with distance from the shore. Superimposed on this general distribution pattern, sites that cleared of snow early in the polar summer were more likely to be occupied by aphids. The phenology of the aphid was significantly affected by small changes in microclimate over distances of a few metres. The aphid only occurs in the warmer parts of the region, but laboratory cultures were successfully reared on plant material collected from colder regions that the aphid does not presently occupy. These observations suggest that the local distribution of A. svalbardicum is determined by summer thermal conditions. On a smaller scale, within patches where the aphids occurred, densities were higher on flowers and flowering shoots than on non-flowering shoots.

Intraspecific variability of Zostera marina L. (eelgrass) in the estuaries and lagoons of the southwestern Netherlands. I. Population dynamics

Within one geographical region the life-history of different populations of Zostera marina L. (eelgrass) occuring under varying environmental conditions was followed for 2 years. Life-history strategies ranged from annual to perennial. Comprehensive data on biomass, density, generative reproduction, growth rate and production are given, compared with information in the literature, and discussed. Among populations, total annual above-ground production ranged between 160 and 412 g AFDW (ash-free dry weight) per m 2 per year, below-ground production varied from 53 to 132 g AFDW per m 2 per year. Flowering shoots had significantly higher growth rates compared with non-flowering shoots. Populations allocated a comparable part of total production towards below-ground structures (22–30%), but investment in reproductive tissue varied widely (1–34%). (Semi-) annuals could be distinguished from perennials by a number of characteristics: relatively small below-ground biomass, high above-ground relative growth rate, high generative reproduction effort and seed production, later seasonal timing and a high variability from year to year. The present study gives substantial data to support the theory that Z. marina in principle strives towards a perennial life-history, while life-histories of the species can range between two extremes (annual and perennial) along a continuum.

THE EFFECT OF TEMPERATURE ON CARBON GAIN IN ALSTROEMERIA

Leaf and whole plant gas exchange (net photosynthesis Pn, dark respiration Dr, transpiration Tr, and resistance R) of `Jacqueline' Alstroemeria, grown in pots inside a greenhouse, were measured under lab conditions using an openflow and a semi-closed system respectively. Temperature responses of apical fully expanded leaves, on flowering and non-flowering shoots, showed an optimum range for net photosynthesis (Pn) from 15 to 20 °C. Above 25 °C Pn dropped considerably as temperature increased. Leaf transpiration rates over the same range of temperature showed a similar decrease, indicating that low leaf Pn rates at higher temperatures were due in part to increased stomatal resistance. Whole plant photosynthetic response to temperature was similar to that of leaf gas exchange. The optimum temperature range for whole plant Pn was from 12 to 17 °C. These results show that moderately low temperatures are essential for carbon assimilation and efficient water use in Alstroemeria. Temperature interactions with other environmental factors will also be presented in models describing Pn rates as a function of irradiance, CO2 concentration, and temperature.

EM-algorithm as a tool for structure analysis of stands of the common reed ( Phragmites australis)

The frequency distributions of morphometric and mechanical properties of randomly sampled stalks of seven reed stands at Lake Constance-Untersee are analysed by the Estimation-maximisation Algorithm. The aim was to look for composed (bimodal) distribution indicating at least two different stem types. In each stand, between one and nine parameters are found to give a bimodal distribution. The two stem types are ‘flowering shoots’ and ‘non-flowering shoots’. The means of nearly all parameters investigated are different at the 1% level of significance. The flowerless shoots are identical with ‘secondary shoots’ and the flowering shoots refer to terminal (= ‘primary’) shoots. The separation of stem types allows investigation of the stand structure and the influence upon it by ‘rhizome-internal’ and ‘external’ factors in more detail.

ウンシュウミカンの花芽分化に及ぼす土壌乾燥と温度条件

The effects of soil drought and temperature on flower bud differentiation of one-year-old satsuma trees (cv. Okitsu Wase) on trifoliate orange were investigated. Potted trees were grown in 15, 20 and 25°C growth chamber rooms and in the field for 6 months from mid June, when new spring leaves turned greenish and the stems were full. Water was supplied at 3 grades of water stress of the trees by monitoring the daily pot weight decrease. Flower bud differentiation was estimated by counting the number of flowers and non-flowering shoots on the trees after defoliating and transferring the trees into the 25°C room in mid December.Trees at lower temperatures produced more flowers and fewer shoots. Trees with optimum soil moisture and medium drought at 25°C did not produce any flowers, but produced some shoots. Only high drought pots produced many flowers. When the soil was dried, the trees tended to have many flowers, flowering nodes and flowers per node at 20°C and in the field. At 15°C, few shoots sprouted, but many leafless flowers occurred regardless of soil moisture. Low temperature treatments produced many flowers from compound buds in an axillary bud, and drought treatments enhanced these trends. Number of flowers in the field was about the same as in a 20°C room, but less than in a 15°C room.