Temporal patterning of blooming phenology in Pedicularis on Mount Rainier

1983 ◽  
Vol 61 (3) ◽  
pp. 786-791 ◽  
Author(s):  
Virginia Dale Adams
Keyword(s):  
Pollen Grains ◽  
Growing Season ◽  
Sympatric Species ◽  
Temporal Patterning ◽  
Flowering Pattern ◽  
Subalpine Meadow ◽  
Evolutionary Force ◽  
Mount Rainier ◽  
Pollinator Sharing ◽  
Blooming Phenology

The temporal patterning of flowering of five sympatric species of Pedicularis in a subalpine meadow is documented. Two species bloom early in the growing season, one is intermediate, and two flower toward the later part of the season. The differences between species are related to the range of blooming periods (in days), the number of inflorescences at maximum bloom, and the time of peak bloom. No significant variation in flowering pattern occurred during the years of observation (1977, 1978, and 1979). More than 93% of the time individual bumblebees continued to forage on the same Pedicularis species as was previously visited; yet when switches in the diet of the bees occurred, they were more likely to be to another species of Pedicularis. Although individuals of other genera were in bloom, the bees switched to the Pedicularis species most synchronous in time and space to the previously preferred Pedicularis species. Counts were made of the number of pollen grains per flower, the reward for foraging bees. The last species to flower had the greatest reward but also had the largest ratio of the number of pollen grains to the number of ovules as compared with the previously flowering Pedicularis species. These results suggest that pollinator sharing is an important evolutionary force but that the quantity of the pollen reward may be more related to the number of ovules.

Flowering phenology of tropical-alpine dwarf trees on Mount Kinabalu, Borneo

2004 ◽  
Vol 20 (5) ◽  
pp. 563-571 ◽  
Author(s):  
Gaku Kudo ◽  
Shizuo Suzuki
Keyword(s):  
Flowering Phenology ◽  
Plant Size ◽  
Sympatric Species ◽  
Fruit Production ◽  
Flowering Pattern ◽  
Flowering Synchrony ◽  
Mount Kinabalu ◽  
Main Plot ◽  
Tropical Alpine ◽  
Summit Region

The flowering phenology of five alpine dwarf-tree species was observed in the summit region (3900–3950 m elevation) of Mt. Kinabalu on Borneo Island from March 1998 to November 2001. For each target species, 20–50 individual plants were numbered in two observation plots and the number of inflorescences was monitored at 2–3-mo intervals. The flowering patterns varied among species. Rhododendron buxifolium bloomed extensively every March–May at the main plot but the flowering pattern at the subplot was less predictable. Mass flowering occurred in March 1998 when drought stress was very severe due to an El Niño event. Rhododendron ericoides showed continuous flowering throughout the year and high synchrony between the plots. Extensive flowering of Leptospermum recurvum occurred synchronously within and between plots in the early half of 1999, then flowering activity decreased greatly. Photinia davidiana showed an annual flowering cycle but the timing of the peak flowering differed between the plots. Vaccinium stapfianum showed synchronous flowering between the plots and the flowering peak appeared at longer than 1-y intervals. Plant size was positively correlated with mean flower production in all species, and with the flowering frequency of R. ericoides, R. buxifolium, and V. stapfianum at one of the plots at least. Two fleshy-fruited species, P. davidiana and V. stapfianum, had high selfing ability for fruit production and showed relatively low flowering synchrony among individuals in comparison with the other species. These results indicate that the trigger for initiation of flowering may differ among sympatric species in a tropical-alpine ecosystem at least in normal years.

Agronomic variation in Centrosema virginianum in relation to its use as a sub-tropical pasture plant

1977 ◽  
Vol 17 (86) ◽  
pp. 435 ◽  
Author(s):  
RJ Clements
Keyword(s):  
Growing Season ◽  
North Coast ◽  
Tropical Pasture ◽  
Flowering Pattern ◽  
Seedling Regeneration ◽  
South Eastern ◽  
Herbage Yield ◽  
Macroptilium Atropurpureum ◽  
Potential Improvement ◽  
Pasture Plant

Nineteen accessions of Centrosema virginianum were grown in replicated short rows at four sites in south-eastern Queensland and one site on the wet tropical north coast, and some of their agronomic characteristics were observed and compared with those of Macroptilium atropurpureum cv. Siratro. Three sites were abandoned when the accessions grew poorly or died during the winter, although Siratro survived and grew vigorously. At the remaining sub-tropical sites the accessions persisted under weed-free conditions where seedling regeneration more than compensated for plant losses during the winter. In the second season at these sites, rows were cut for herbage yield assessment either every six weeks during the growing season or once at the end of the season. Treatments were continued for a third season at one site. In most respects Siratro was superior to all C. virginianum accessions. The accessions differed considerably in herbage yield, winter survival, seed production, seedling regeneration and leafiness, and differed slightly in leaf and stem digestibility. Many accessions flowered for very long periods in south-eastern Queensland, in contrast to the markedly bimodal flowering pattern of Siratro, but peak flowering dates of the accessions in the autumn differed by up to three months. Both C. virginianum and Siratro showed a reduction in percentage pod set during the middle of the growing season. Variation between accessions is discussed in relation to potential improvement of C. virginianum by plant breeding.

Cucumis anguria (West Indian gherkin).

2021 ◽  
Author(s):  
Julissa Rojas-Sandoval
Keyword(s):  
Pollen Grains ◽  
Growing Season ◽  
Low Fertility ◽  
Annual Rainfall ◽  
Editorial Committee ◽  
Male And Female ◽  
Tropical Plants ◽  
Wide Range ◽  
Male Flowers ◽  
Female Flowers

Abstract Genetics: The chromosome number reported for Cucumis anguria is 2n=24 (Ramachandran and Narayan, 1990; Flora of North America Editorial Committee, 2020). Reproductive Biology: Cucumis anguria is a monoecious species, with individual male and female flowers appearing on both plants, that depends of pollinators to transfer pollen grains in order to produce fruits. Although self-fertile, a degree of outcrossing results from insect pollination. Zagorcheva (1988) has suggested that C. anguria may also be a facultative apomict. The flowering season is of about 55-58 days. Male flowers appear before female flowers and both male and female flowers remain open for one day (from 7:30 am to 4:00 pm). The relationship between male and female flowers is on average 5.5 male flowers for each female flower. The greater number of male flowers compared to female flowers produces a greater flow of pollen in the crop and ensures pollination. Flowers are visited and pollinated by insects. In a study in Brazil, the most important visitor was Apis mellifera (72% of all visits) followed by native bees from the genera Plebeia sp. (16.7%), Exomalopsis sp. (8.3%) and Melissodes sp. (2.8%). Flowers are also visited by butterflies (Malerbo-Souza et al., 2020). Physiology and Phenology: Cucumis anguria is an annual species. Early growth is upright, followed by branching at the base to produce several trailing stems. Within its native distribution range, this species germinates in a few days during the summer rains when night temperatures are above 12°C and the soil is sufficiently wet. When plants are about 2-3 m length, they start to develop flowers. Fruits are often produced within 60 days after germination. Plants may produce up to 50 fruits per stem. Fruits remain attached to the withered annual stems long after these have died back at the end of the growing season (Wilkins-Ellert, 2004). Photoperiod is important and longer days coupled with higher temperatures confines plants to the production of male flowers. Shorter days and a drop in temperature stimulate the production of female flowers. Fruiting occurs within 60 days of planting and fruit are produced continuously, with as many as 50 fruits per plant produced during the growing season (Wilkins-Ellert, 2004). Environmental Requirements: Cucumis anguria prefers to grow in tropical and subtropical climates. It grows best in areas with mean annual temperatures ranging from 15°C to 28°C (tolerates 8°C-35°C) and mean annual rainfall between 800 mm-1000 mm (tolerates 300 mm-1700 mm). It is well adapted to soils with low fertility and is adapted to grow in a wide range of soil types, including Kalahari sands (regosols), red clays and black cotton soils (vertisols) with pH in the range 6-7.5 (tolerates 5.5 - 8.3), but it grows best on well drained sandy soils (Fernandes, 2011). This species is sensitive to cold and does not tolerate frost (Wilkins-Ellert, 2004; Useful Tropical Plants, 2020).

scholarly journals Flowering of siberian peashrub (Caragana arborescens Lam.) and its forage value to pollinating insects

2014 ◽  
Vol 67 (3) ◽  
pp. 13-20 ◽  
Author(s):  
Ernest Stawiarz ◽  
Anna Wróblewska
Keyword(s):  
Pollen Grains ◽  
Growing Season ◽  
Average Weight ◽  
Pollen Production ◽  
Flowering Period ◽  
Caragana Arborescens ◽  
Pollinating Insects ◽  
Nectar Sugar ◽  
Single Flower ◽  
Forage Value

<p class="abstracttekst">Under the conditions of Lublin (central-eastern Poland), observations were conducted on the flowering of <em>Caragana arborescens </em>shrubs for two growth seasons as well as nectar and pollen production by the flowers of this species was investigated.</p><p class="abstracttekst">The flowering period of <em>Caragana arborescens </em>began at the turn of April and May and lasted for 24 days, while for a single flower it was 6.30 ± 0.79 days. The average weight of nectar, sugars and pollen produced by 10 Siberian peashrub flowers was, respectively: 46.70 ± 8.39 mg, 22.79 ± 6.10 mg, and 4.45 ± 0.34 mg. The nectar sugar concentration amounted 49.60 ± 10.08%. Pollen grains reached average dimensions of 21.94 ± 0.76 µm x 21.52 ± 0.71 µm. During a growing season, one <em>Caragana arborescens</em> shrub can provide on average 101.8 g of nectar, 49.7 g of sugars, and 9.7 g of pollen.</p>

scholarly journals Does Drought Stress on Seedlings Have Longer Term Effects on Sapling Phenology, Reshooting, Growth and Plant Architecture in Quercus robur, Q. petraea and Their Morphological Intermediates?

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 1012 ◽  
Author(s):  
Kristine Vander Mijnsbrugge ◽  
Arion Turcsan ◽  
Stefaan Moreels ◽  
Michiel Van Goethem ◽  
Steven Meeus ◽  
...  
Keyword(s):  
Drought Stress ◽  
Quercus Robur ◽  
Western Europe ◽  
Plant Architecture ◽  
Growing Season ◽  
Treated Group ◽  
Sympatric Species ◽  
Drought Treatment ◽  
After Effects ◽  
Effects Of Drought

Background and Objectives: Summer droughts are expected to increase in central and western Europe both in terms of frequency and intensity, justifying studies on longer term legacies of drought stress on tree species and their hybrids. Materials and Methods: We studied the longer-term after effects of water withholding and re-watering in the first growing season of potted seedlings from the sympatric species Quercus robur L., Q. petraea (Matt.) Liebl. and their morphological intermediates. Phenology, growth, and plant architecture were examined after a cut-back of the stems at the end of the third growing season. Results: The legacy of the first-year water limitation is faded in the phenological response. Nonetheless, leaf senescence occurred later in offspring from Q. robur than in offspring from Q. petraea at the end of the fourth growing season and leafing out tended to be later in the subsequent growing season. Offspring from the intermediate forms displayed variable phenological responses. Height and radial growth were still affected by the drought stress in a taxon-dependent way, with the offspring from Q. petraea displaying growth reduction both in height and diameter, whereas offspring from Q. robur did not show any differences anymore between control and treated plants, demonstrating better post-stress recovery in Q. robur. Offspring from morphological intermediates responded again in a variable way. Although the number of reshoots after cutting back the stems was not affected anymore by the drought treatment in the first growing season, the number of side shoots on the reshoots was still reduced in the drought treated group of plants, independent of the taxon of the mother tree. Conclusions: Together, our results demonstrate the longer-lasting effects of drought stress on oak saplings with regard to growth and plant architecture, with the first being taxon dependent.

scholarly journals Floral phenology and pollen production in the five nocturnal Oenothera species (Onagraceae)

2018 ◽  
Vol 71 (2) ◽  
Author(s):  
Sebastian Antoń ◽  
Bożena Denisow
Keyword(s):  
Unit Area ◽  
Pollen Grains ◽  
Early Morning ◽  
Pollen Production ◽  
Invasive Potential ◽  
Se Poland ◽  
Floral Phenology ◽  
Late Evening ◽  
Species Specific ◽  
Blooming Phenology

Blooming phenology and pollen production in the five <em>Oenothera</em> species were investigated during the period of 2013–2015 in the Lublin area, SE Poland. The blooming period was relatively long, and flowering usually started in the middle or late June and lasted until late July or the middle of August. The <em>Oenothera</em> species studied exhibited nocturnal anthesis, i.e., the flowers opened in the late evening and lasted overnight until the early morning hours. Plants developed a great number of flowers per individual and per unit area (on average, 158 and 4,136, respectively), and this feature appeared to be species-specific. It was demonstrated that the blooming phase had an impact on the mass of anthers and pollen produced per flower in all <em>Oenothera</em> species. In general, the greatest mass of anthers and pollen was observed at the beginning of blooming, and with the progress of flowering, the values decreased. However, statistical differences were found for <em>O. flaemingina</em>, <em>O. paradoxa</em>, and <em>O. rubricaulis</em>. The mass of pollen produced per unit area was also a species-specific characteristic and was related to the abundance of flowering. The greatest amount of pollen was produced by <em>O. flaemingina</em> (30.6 g m<sup>−2</sup>), which was almost three times more than that produced by <em>O. rubricaulis</em> (10.9 g m<sup>−2</sup>). The protein content of pollen grains was relatively low and on average amounted to 15.4%. The <em>Oenothera</em> species examined in this work may be considered valuable pollen yielding plants. Nevertheless, given the invasive potential of species from subsect. <em>Oenothera</em>, precautions are suggested during cultivation and/or planting these taxa in bee pastures, in order to prevent uncontrolled spread into new areas.

ARCTIC AEROPALYNOLOGY: SPORA OBSERVED ON STICKY SLIDES EXPOSED IN VARIOUS REGIONS IN 1950

1955 ◽  
Vol 33 (5) ◽  
pp. 401-415 ◽  
Author(s):  
Nicholas Polunin
Keyword(s):  
Pollen Grains ◽  
Ground Level ◽  
Growing Season ◽  
Baffin Island ◽  
Local Origin ◽  
Northern Areas ◽  
Main Period

Sticky slides were exposed more or less throughout the summer of 1950 in widely scattered arctic and other northern areas including Point Barrow, Alaska, northern-central Baffin Island, Jan Mayen Island, and Spitsbergen. Although the spora were generally sparse and conclusions must be regarded as tentative, it appeared that near ground level the incidence of pollen grains tended in general to coincide with the main period of flowering but that moss spores were in the air more or less throughout the growing season. Most (but by no means all) of the pollen observed could have been of local origin except in Spitsbergen, where there tended to be a preponderance of abietineous winged grains (mostly of Pinus) which were persistently caught practically throughout the brief summer although they had evidently been blown in from at least several hundred miles away.

scholarly journals Symbiotic cyanobacteria communities in hornworts across time, space, and host species

2020 ◽  
Author(s):  
Jessica M. Nelson ◽  
Duncan A. Hauser ◽  
Fay-Wei Li
Keyword(s):  
New York ◽  
Phylogenetic Diversity ◽  
Growing Season ◽  
Sympatric Species ◽  
Soil Samples ◽  
Host Factors ◽  
Upstate New York ◽  
Time Space ◽  
Long Reads ◽  
Microbe Interactions

SummaryRationaleWhile plant-microbe interactions have been intensively studied in mycorrhizal and rhizobial symbioses, much less is known about plant symbioses with nitrogen-fixing cyanobacteria. Here we focused on hornworts (a bryophyte lineage), and investigated the diversity of their cyanobionts and how these communities are shaped by spatial, temporal, and host factors.MethodWe carried out repeated samplings of hornwort and soil samples in upstate New York throughout the growing season. Three sympatric hornwort species were included, allowing us to directly compare partner specificity and selectivity. To profile cyanobacteria communities, we established a new metabarcoding protocol targeting rbcL-X with PacBio long reads.ResultsHornwort cyanobionts have a high phylogenetic diversity, including clades that do not contain other known plant or lichen symbionts. While the sympatric hornwort species have similarly low specificity, they exhibit different preferences toward cyanobionts, although this depended on what cyanobacteria were present in the soil. Cyanobacterial communities varied spatially, even at small scales, but time did not play a major organizing role.Conclusion.This study highlights the importance of sampling soil and sympatric species to infer partner compatibility and preference, and marks a critical step toward better understanding the ecology and evolution of plant-cyanobacteria symbiosis.

scholarly journals Palynological assessment of the atmosphere in the city of Cherepovets

2021 ◽  
Vol 265 ◽  
pp. 06003
Author(s):  
Alexandra Kamygina ◽  
Maria Smirnova ◽  
Natalia Afanasyeva ◽  
Nadezhda Poddubnaya
Keyword(s):  
Woody Plants ◽  
Pollen Grains ◽  
Growing Season ◽  
Hay Fever ◽  
Herbaceous Plants ◽  
Total Spectrum ◽  
Pollen Trap ◽  
Betula Pollen ◽  
The City ◽  
Gravimetric Sampling

The article presents the results of the study of aeropalinological spectra of the city of Cherepovets (59 ° 07′59 ″ N, 37 ° 53′59 ″ E), carried out during the growing season 2014-2015. The method of gravimetric sampling was used (Durham’s pollen trap). Data was obtained on 22 taxa and the dynamics of dusting of various palynomorphs; the dominant taxa of palinospectrum were identified, as well as non-pollen palynomorphs in the air. It is shown that Betula pollen grains prevail in the atmosphere of the city. The pollen of woody plants occupies 80% of the total spectrum, and the pollen of herbaceous plants – 20%. Seasonal highs are recorded twice: in May and in late June – early July. This information must be taken into account when accompanying patients with hay fever.

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