scholarly journals Flowering, nectar secretion, pollen shed and insect foraging on Aquilegia vulgaris L. (Ranunculaceae)

2012 ◽  
Vol 65 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Bożena Denisow ◽  
Sebastian Antoń
Keyword(s):  
Reproductive System ◽  
Sugar Yield ◽  
Pollen Production ◽  
Nectar Secretion ◽  
Flower Opening ◽  
Flower Visitors ◽  
Insect Visitation ◽  
Female Phase ◽  
Pollen Shed

This study on blooming biology, nectar secretion, pollen production and insect visitation of <i>Aquilegia vulgaris</i> L. was carried out in 2009 and 2011 in Lublin. The peak of flower opening during the day was between 5.00 and 7.00 (GMT +2). The flowers are protandrous with the female phase beginning approx. on the 3rd day of anthesis. The dynamics of nectar secretion and pollen shed from anthers (progressing from the central part of the androecium outwards) support the reproductive system. The amount of nectar accumulated in the spurs increased from the bud stage and was the highest in the phase with approx. ¾ of dehisced anthers, usually on the 3<sup>rd</sup> day of flower life. Then, towards the end of anthesis, the amount of secreted and accumulated nectar decreased. The number of anthers developed per flower varied from 41 to 61 (mean = 49.1). The mass of pollen per 100 anthers averaged 6.7 mg. Pollen production per flower (mean = 3.28 mg) slightly varied between years and was mainly correlated with the number of developed anthers. Estimated pollen yield was 1.69 g per m<sup>2</sup> and sugar yield 1.22 g per m<sup>2</sup>. Species from the genus <i>Bombus</i> were the main flower visitors, with <i>B. terrestris</i> being the most frequent forager.

scholarly journals Nectar secretion and pollen production in protandrous flowers of Campanula patula L. (Campanulaceae)

2018 ◽  
Vol 71 (1) ◽  
Author(s):  
Bożena Denisow ◽  
Monika Strzałkowska-Abramek ◽  
Małgorzata Wrzesień
Keyword(s):  
Sugar Accumulation ◽  
Reproductive Costs ◽  
Pollen Production ◽  
Nectar Secretion ◽  
Mass Content ◽  
Plastic Response ◽  
Male And Female ◽  
Functional Relationships ◽  
Female Phase ◽  
Male Phase

Nectar secretion was noted both in the male and female floral phases of the protandrous flowers of <em>Campanula patula</em> (Campanulaceae). Female-biased sugar accumulation was evidenced and plasticity in the duration of sexual phases observed. Flowers in the male phase produced twofold less nectar with lower sugar concentrations compared to female-phase flowers. The sugar mass content averaged 0.6 mg ±0.45 <em>SD</em> per flower in the male phase and 1.4 ±0.5 <em>SD</em> per flower in the female phase. The pollen mass averaged 0.16 mg ±0.10 <em>SD</em> per flower. An understanding of the evolution of functional relationships between floral sexes requires consideration of the compensation of the reproductive costs, including the plastic response to interdependent factors, i.e., photosynthesis and growth, the effect of pollinators, pollen robbers, and external environmental forces.

scholarly journals Flowering and Nectar Secretion in two Forms of the Moldavian Dragonhead (Dracocephalum moldavica L.) – A Plant with Extraordinary Apicultural Potential

2018 ◽  
Vol 62 (1) ◽  
pp. 97-110 ◽  
Author(s):  
Marta Dmitruk ◽  
Elżbieta Weryszko-Chmielewska ◽  
Aneta Sulborska
Keyword(s):  
Sugar Content ◽  
Corolla Tube ◽  
Sugar Yield ◽  
Total Sugar ◽  
Nectar Secretion ◽  
Flower Visitors ◽  
Corolla Length ◽  
Leaf Surfaces ◽  
The Mean

Abstract Dracocephalum moldavica is a valuable reward plant for flower visitors. The aim of the study was to ecologically characterise its flowers and leaves and assess the seasonal and daily dynamics of flowering in two white- and blue-flowered forms of this species in 2004 and 2005. Additionally, the duration and abundance of plant flowering as well as the nectar amount and sugar content were analysed. The signalling attractants of the plant include an intense scent emitted by trichomes located not only on its flowers but also on its stem and leaf surfaces. The average corolla length is 24 mm and the corolla tube, which can be completely filled with nectar, is 8.6 mm long. The floral lifespan was shown to reach 2-3 days and the mean blooming duration of both forms of dragonhead 45-48 days. The white-flowered plants produced a substantially greater number of flowers (5352) than the blue-flowered form (2965). The nectar amount obtained from ten blue flowers was 15.33 mg and that extracted from white flowers reached 17.56 mg, with 49.4% and 51.5% content of sugar, respectively. The total sugar mass produced by one white-flowered plant was 4656 mg, while one blue-flowered plant yielded 2164 mg of sugars. The sugar yield calculated in the study for the white-flowered form (586 kg · ha−1) was two-fold higher than that in the blue-flowered plants.

Floral Morphology of Eucalyptus melliodora A. Cunn. ex Schau. And Comparisons With Other Eucalypt Species

1989 ◽  
Vol 37 (2) ◽  
pp. 125 ◽  
Author(s):  
MW Moncur ◽  
DJ Boland
Keyword(s):  
Floral Development ◽  
Floral Morphology ◽  
Pollen Grains ◽  
Scanning Electron Micrographs ◽  
Nectar Secretion ◽  
Flower Opening ◽  
Outer Whorl ◽  
Close Proximity ◽  
Pollen Shed ◽  
Bud Initiation

The important phases of floral development in E. melliodora from bud initiation to anthesis and style abscission are documented by means of scanning electron micrographs. Thirteen phases of bud development from first indication of operculum abscission to style abscission are presented, as well as the timing and duration of each phase. Anther dehiscence commences prior to flower opening and no pollen grains were observed on flowers 2 days after opening. Secondary transportation of pollen after deposition is possible. Nectar secretion did not commence until after pollen was shed and the stigma became receptive. Although individual flowers were protandrous, there was some overlap within a single inflorescence between pollen shed and the 'wet stigma' phase, suggesting that geitonogamy was possible. The style did not increase in length following anthesis, a common feature in Eucalyptus, leaving the stigma in close proximity with the anthers. There was a graduation in filament length from the outer to inner whorls. The innermost anthers produced the most pollen grains while the outermost were staminodal. There was considerable difference between the number of stamens (71-312), staminodes (0-83) and pollen grains per anther (643-1790) found in the six species examined. Stamen length in all species increased across the staminophore from 1.82-6.99 mm in the inner whorl to 4.84-12.61 mm in the outer whorl.

scholarly journals Intraflower variation in nectar secretion: Secretion patterns and pollinator behavior in male- and female-phase flowers

2018 ◽  
Vol 105 (5) ◽  
pp. 842-850 ◽  
Author(s):  
Ando Misaki ◽  
Tomoyuki Itagaki ◽  
Yutaka Matsubara ◽  
Satoki Sakai
Keyword(s):  
Nectar Secretion ◽  
Male And Female ◽  
Pollinator Behavior ◽  
Female Phase

scholarly journals The Flowering, Pollen Production, and Insect Visitors in the Ornamental Shrub Potentilla Fruticosa L. (Rosaceae)

2013 ◽  
Vol 57 (1) ◽  
pp. 95-106 ◽  
Author(s):  
Bożena Denisow ◽  
Sebastian Antoń ◽  
Grażyna Szymczak
Keyword(s):  
Urban Areas ◽  
Ornamental Plants ◽  
Pollen Production ◽  
Flowering Pattern ◽  
Potentilla Fruticosa ◽  
Full Flowering ◽  
Insect Visitation ◽  
Pollen Productivity ◽  
Ornamental Shrub ◽  
Insect Visitors

Summary Urban areas have a specific ecological environment and may help to sustain local pollinator populations by the cultivation of different ornamental plants with entomophilous flowers. This yearlong study examined the flowering pattern, abundance of flowering, pollen production as well as insect visitation of two cultivars of the ornamental shrub Potentilla fruticosa L. (‘Maanleys’ and ‘Blink’), grown in Lublin; a city in south-eastern Poland. P. fruticosa ‘Maanleys’ bloomed from the middle of May to the first decade of September and P. fruticosa ‘Blink’ from June until October. The pattern of diurnal flowering was similar for both cultivars and showed plasticity in the season. Flowers opened most intensively in the morning hours, and 80 - 90% of the daily installment of newly opened flowers expanded by 8.00 h GMT +2h. A delay in the peak of diurnal flowering was noted between the spring/summer and summer/autumn periods. The most intense blooming fell in the 2nd month of flowering. The mass of pollen produced per flower depended on both the number of anthers and the efficiency of archesporial tissues. The pollen output varied from 1.4 to 7.2 mg per 10 flowers (‘Maanleys’) and from 2.6 to 4.5 mg per 10 flowers (‘Blink’). The mass of pollen produced per individual shrub was substantially related to the abundance of blooming. The average estimated pollen productivity in the full flowering phase was low; 1 g (‘Maanleys’) and 1.5 g (‘Blink’) per 10 m2 of shrub crown. The flowers of Potentilla fruticosa attracted numerous insects, mainly solitary bees (33 - 43%), dipterans (31 - 42%), lepidopterans (4 - 14%), bumblebees (3 - 15%), and honey bees (3 - 4%). The Potentilla fruticosa ‘Maanleys’ and ‘Blink’ are propagated for specific ornamental arrangements and due to a long flowering period may be used in small urban courtyards for both decorative value and as a pollen delivering plants.

scholarly journals Comparative reproduction mechanisms of three species of Ocimum L. (Lamiaceae)

2016 ◽  
Vol 69 (1) ◽  
Author(s):  
Matthew Oziegbe ◽  
Temitope Olatayo Kehinde ◽  
Joshua Olumide Matthew
Keyword(s):  
Reproductive System ◽  
Seed Set ◽  
Ocimum Basilicum ◽  
The Self ◽  
Self Pollination ◽  
Insect Visitation ◽  
Open Treatment ◽  
Fruit And Seed Set

<em>Ocimum</em> species have a combination of reproductive system which varies with the locality and cultivar. We have studied here the reproductive mechanisms of five variants of three <em>Ocimum</em> species in Nigeria, namely: <em>Ocimum canum</em> Sims., <em>O. basilicum</em> L., and <em>O. americanum</em> L. Flowers from each variant were subjected to open and bagged pollination treatments of hand self-pollination, spontaneous self-pollination and emasculation. All open treatments of the five <em>Ocimum</em> variants produced more fruit and seed than the corresponding bagged treatments. The two <em>O. canum</em> variants and <em>O. basilicum</em> ‘b<span><sub>1</sub></span>’ produced high fruit and seed set in the open and bagged treatments of spontaneous self-pollination. <em>Ocimum basilicum</em> ‘b<span><sub>2</sub></span>’ and <em>O. americanum</em> produced higher fruit and seed set in the self-pollination open treatment but significantly lower fruit and seed set in the bagged treatment. Fewer fruit and seeds were produced in the emasculated open treatments but none in the emasculated bagged treatments of the five <em>Ocimum</em> variants. The floral foragers comprising of bees, wasps and butterflies visited the <em>Ocimum</em> species to collect pollen or nectar in the open treatments. The two <em>O. canum</em> variants and <em>O. basilicum</em> ‘b<span><sub>1</sub></span>’ variant reproduced mainly through autogamy but <em>O. basilicum</em> ‘b<span><sub>2</sub></span>’ and <em>O. americanum</em> showed mixed reproduction of autogamy and outcrosssing. Insect visitation to the flowers enhanced pollination resulting in higher fruit and seed set in all the <em>Ocimum</em> species studied.

scholarly journals Wind to insect pollination ratios and floral traits in five alpine Salix species

1999 ◽  
Vol 77 (4) ◽  
pp. 556-563 ◽  
Author(s):  
Liza Peeters ◽  
Ørjan Totland
Keyword(s):  
Plant Traits ◽  
Pollen Dispersal ◽  
Negative Relationship ◽  
Field Work ◽  
Floral Traits ◽  
Wind Pollination ◽  
Pollen Production ◽  
Insect Pollination ◽  
Insect Visitation ◽  
Nectar Content

This study examines the ratio of wind to insect pollination of five alpine-arctic Salix species and possible correlations between plant traits and this ratio. The field work was done in an alpine area in southwest Norway, at an elevation of 1250 m. Female catkins were enclosed within mesh cloth to prevent insect visitation, and their fruit set was determined and compared with that of open-pollinated control catkins. Simultaneously, pollen production per anther, pollen dispersal, standing crop of nectar, flower length, number of flowers per catkin, and catkin length were measured. The amount of wind pollination of the species varied from 2 to 52%. All species spread pollen in the air. Nectar content, catkin length, flower number, and flower length showed a negative relationship with the percentage of wind pollination. Significant negative linear correlations between female catkin length and flower length and amount of wind pollination were detected. Pollen production per anther did not show any relationship to the pollination system. We suggest that the evolution to insect pollination in alpine Salix species may have resulted in a lengthening of anthers and pistils, and an increase in nectar production.Key words: alpine, anemophily, entomophily, floral traits, pollination, Salix.

scholarly journals Nectar and Pollen Production and Insect Visitation on Ornamentals from the Genus Hosta Tratt. (Asparagaceae)

2015 ◽  
Vol 59 (2) ◽  
pp. 115-125 ◽  
Author(s):  
Małgorzata Bożek ◽  
Monika Strzałkowska-Abramek ◽  
Bożena Denisow
Keyword(s):  
Pollen Grains ◽  
Polar View ◽  
Shape Index ◽  
Flowering Phenology ◽  
Botanical Garden ◽  
Agricultural Landscapes ◽  
Phenotypic Traits ◽  
Pollen Production ◽  
Insect Visitation ◽  
Perianth Tube

Abstract Properly arranged ornamental gardens in both urban and agricultural landscapes can be of a benefit to bees. In this study, we observed the flowering phenology, nectar, and pollen production of the ornamental Hosta species and varieties (H. sieboldiana Engler, H. capitata Nakai, H. crispula Maekawa, H. fluctuans Maekawa, syn. H. sieboldiana var. fluctuans hort., H. undulata var. univittata Miquel (Hylander), syn. H. univittata). Our experiment was conducted in the 2012 - 2014 time period, at the UMCS Botanical Garden in Lublin, Poland (51° 14’ N, 21° 34’ E). The total sugar yield varied almost 5-fold among Hosta ornamentals; the lowest amount was calculated for H. fluctuans (2.31 g per 10 m2) and the highest for H. capitata (11.80 g per 10 m2). The average pollen yield was from 0.24 g per 10 m2 (H. undulata var. univittata) to 9.53 g per 10 m2 (H. capitata). Pollen grains were bilaterally symmetrical, and large-sized. In polar view, they were prolatum (shape index 1.33 - 1.61), while in equatorial view, oblatum (shape index 0.5 - 0.7). Hosta species can complete the summer pasture mainly for bumblebees. In four of the five Hosta representatives, bumblebees accounted for 60 - 70% of the total visits. The honeybee predominated only on the flowers of H. capitata (54 - 71%). Solitary bees were rarely observed (3 - 9% of visits). The phenotypic traits of Hosta flowers (the accumulation of nectar in the deep and narrow perianth tube) reduced the access to nectar reward and restricted an array of insect visitors.

scholarly journals Preferential reproduction mode of hermaphrodite papaya plant (Carica papaya L; Caricaceae)

2009 ◽  
Vol 31 (1) ◽  
pp. 182-189 ◽  
Author(s):  
Pedro Corrêa Damasceno junior ◽  
Telma Nair Santana Pereira ◽  
Messias Gonzaga Pereira ◽  
Francisco Filho da Silva ◽  
Margarete de Magalhães Souza ◽  
...  
Keyword(s):  
Reproductive System ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Acetate Solution ◽  
Flower Bud ◽  
Stigma Receptivity ◽  
Flower Opening ◽  
Reproduction Mode ◽  
Pollen:Ovule Ratio

This research was done to study the reproductive system of papaya hermaphrodite plant based on the histochemical nature of pollen grain, stigma receptivity, in vivo pollen grain germination and pollen:ovule ratio. In the histochemical analysis, pollen grains were stained by using Sudan IV and I2KI solution ; the stigma receptivity was assessed by alpha-naphthtyl acetate solution in closed and opened flowers. Pollen germination and pollen tube growing were examined in flower buds near anthesis with 0.1% aniline blue. To estimate the pollen:ovule ratio , anthers from each flower bud were dissected and all pollen grains were counted; ovules were dissected from ovaries and were counted under stereomicroscope. The results indicated that papaya pollen grains are of lipidic nature; the stigmas were receptive before the opening and until 48 hours after opening; the pollen grains germinated and emitted polinic tube before flower opening and the pollen:ovule ratio indicated the predominance of autogamous reproductive system. These results indicate that hermaphrodite papaya trees is preferentially of optional autogamous with cleistogamy.

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