Wyniki wyszukiwania

1

Pyrrolizidine alkaloids in European honeys and honeys from overseas

100%

Dubecke A., Beckh G., Lullmann C.

Polish Journal of Food and Nutrition Sciences

|

2011

|

tom 61

|

nr Suppl.1

2

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Ecophysiological aspects of nectar reabsorption

100%

Stpiczynska M., Nepi M.

Acta Agrobotanica

|

2006

|

tom 59

|

nr 1

A number of approaches, both direct and indirect, have shown that nectar is reabsorbed by numerous plant species, irrespective of the age or sex of the flower. Furthermore, reabsorption occurs regardless of whether or not the flower has been pollinated. Reabsorption helps to maintain concentration of nectar and their viscosity and thereby encourages continued visits by pollinators. Conversely, the capacity to vary concentration of nectar sugars may confer evolutionary advantage by encouraging visits by more than one kind of pollinator and this is particularly important in regions where there is a paucity of pollinators. A further important role of nectar reabsorption is the maintenance of the energy equilibrium of the plant. A number of studies have shown that nectar production involves considerable energy expenditure requiring as much as 37% of the plant's daily production of energy by photosynthesis. The increased metabolic costs incurred by the plant during nectar production and secretion can reduce its growth and reproduction during the following season. Reabsorption of nectar that has not been collected by pollinators enables the plant to conserve at least some of the energy reserved for the secretion of nectar. Sugars reabsorbed from nectar can be re-used for the development of fruit and ovules - processes which demand large quantities of sugar. Despite convincing evidence for the reabsorption of nectar, few detailed studies have addressed the transport and incorporation of reabsorbed sugars. One of the questions that remain to be answered is 'What is the cellular basis for nectar reabsorption by the nectary?'.

3

Risk-taking and foraging strategy in honey bee workers collecting nectar and water

100%

Woyciechowski M.

Pszczelnicze Zeszyty Naukowe

|

1998

|

tom 42

|

nr 2

4

The effect of silicon on nectar and pollen production in Hosta Tratt. ‘Krossa Regal’

84%

Denisow B., Pogroszewska E., Laskowska H.

Acta Scientiarum Polonorum. Hortorum Cultus

|

2015

|

tom 14

|

nr 4

Recently, the importance of silicon (Si) has been demonstrated for many plant physiological processes. The recognized function of Si is to help plants to overcome multiple biotic and abiotic stresses, e.g. disease or pests, low temperature, water deficit, salinity or heavy metals. Silicon advantageously impact on plant development and may improve the quality of ornamental plants. Hosta is an ornamental perennial, that flowers can serve as a source of nectar and pollen for floral visitors. The effect of artificial silicon (Si) supply on flowering, nectar production and pollen traits in Hosta Tratt. ‘Krossa Regal’ was studied. A foliar spraying of 0, 120, 180 and 240 mg Si·dm–3 was applied with water solutions of Actisil Hydro Plus, containing silicon in the form of H4SiO4. Silicon supply in concentration of 180 and 240 mg Si·dm-3 affected the morphometric traits of the flower (perianth width and floral tube length), but not the number of flowers produced per inflorescence. The silicon supply in concentration of 180 and 240 mg Si·dm-3 resulted in the increase of nectar production and in sugars excess in floral nectar. Treatments in concentration of 180 and 240 mg Si·dm-3 positively influence both pollen production and pollen viability. Presumably, most of these results can be explained through the effect of the Si on metabolism enhancement, e.g. by water balance regulation and increase in photosynthetic efficiency.

5

Nectary structure of Ornithidium sophronitis Rchb.f. (Orchidaceae: Maxillariinae)

84%

Stpiczynska M., Davies K. L., Gregg A.

Acta Agrobotanica

|

2009

|

tom 62

|

nr 2

Most orchids do not produce floral food-rewards. Instead, they attract pollinators by mimicry or deceit. When present, the most common floral food-reward is nectar. To date, nectary structure has been described for only two species of Maxillaria sensu lato, namely Maxillariella anceps and Ornithidium coccineum (formerly Maxillaria anceps and M. coccinea, respectively). Here, we describe that of a third species, Ornithidium sophronitis (formerly Maxillaria sophronitis). This species possesses floral characters concomitant with ornithophily. A ‘faucet and sink’ arrangement is present, with nectar secreted by a protuberance on the ventral surface of the column, collecting between column and tepal bases. The nectary of O. sophronitis shares many features with that of O. coccineum. It has a single-layered epidermis and 3- 5 layers of small, subepidermal, collenchymatous, secretory cells. Beneath these occur 2-3 layers of larger, subsecretory, parenchymatous cells supplied by phloem. Nectary cell vacuoles contain osmiophilic material and proteinaceous intravacuolar bodies. Moreover, distension of the nectary cuticle occurs as nectar accumulates between it and the secretory epidermis. Subsecretory cells, however, have thinner walls and contain flocculent, intravacuolar precipitates that may be related to the presence of flavonoids. Since the floral and nectary structure of O. sophronitis is very similar to that of closely related Ornithidium coccineum, it may have evolved in like manner in response to similar pollinator pressures.

6

Variability in nectar and pollen production in flowers of double-low lines of white mustard (Sinapis alba L.) and their attractiveness to honey bees

84%

Masierowska M., Pietka T.

Acta Scientiarum Polonorum. Hortorum Cultus

|

2014

|

tom 13

|

nr 5

The studies concerned the variability in nectar and pollen production in flowers of 75 double-low lines of white mustard (Sinapis alba L.) and a reference cultivar ‘Nakielska’. Also, rates of insect visitation to flowers in 19 lines were investigated. Significant genotypic differences were found in nectar amount, sugar concentration in nectar and total nectar sugar amount. The average nectar amount/10 flowers varied from 2.3 to 24.4 mg, with a mean 14.7 mg for ‘Nakielska’. Nectar concentration for most lines exceeded 20%. The majority (52%) of the lines tested produced more than 2 mg of sugars/10 flowers in nectar. The average amounts of pollen varied from 1.2 to 12.0 mg/10 flowers, with the mean 8.5 mg for ‘Nakielska’. No clear genotypic effect on the amount of pollen/10 flowers was demonstrated. The lines did not differed significantly in their attractiveness to flower visitors. The main foragers were honey bees (93% of all visiting insects). It is concluded that the double-low lines of S. alba are comparable to conventional cultivars in their potential for nectar flow but perform poorer as pollen producers. The studies concerned the variability in nectar and pollen production in flowers of 75 double-low lines of white mustard (Sinapis alba L.) and a reference cultivar ‘Nakielska’. Also, rates of insect visitation to flowers in 19 lines were investigated. Significant genotypic differences were found in nectar amount, sugar concentration in nectar and total nectar sugar amount. The average nectar amount/10 flowers varied from 2.3 to 24.4 mg, with a mean 14.7 mg for ‘Nakielska’. Nectar concentration for most lines exceeded 20%. The majority (52%) of the lines tested produced more than 2 mg of sugars/10 flowers in nectar. The average amounts of pollen varied from 1.2 to 12.0 mg/10 flowers, with the mean 8.5 mg for ‘Nakielska’. No clear genotypic effect on the amount of pollen/10 flowers was demonstrated. The lines did not differed significantly in their attractiveness to flower visitors. The main foragers were honey bees (93% of all visiting insects). It is concluded that the double-low lines of S. alba are comparable to conventional cultivars in their potential for nectar flow but perform poorer as pollen producers.

7

Adaptations of Lamium album L. flowers to pollination by Apoidea

84%

Sulborska A., Dmitruk M., Konarska A., Weryszko-Chmielewska E.

Acta Scientiarum Polonorum. Hortorum Cultus

|

2014

|

tom 13

|

nr 6

The presence of ruderal and mid-field vegetation promotes conservation of biodiversity and provides an additional source of food for insect pollinators. The white deadnettle is a common synanthropic plant visited frequently by various groups of insects, as it is a source of pollen and nectar. In 2012–2013, in the city of Lublin (Poland), signalling and food attractants in L. album flowers were analysed using light and scanning electron microscopy. The pipetting method was used for determination of nectar abundance in the flowers, and the content of sugars in the nectar was assessed with the use of an Abbe refractometer. It was found that the white dead-nettle flowers emitted a fragrance and were equipped with nectar guides, and the corolla and stamens had glandular trichomes and papillae secreting essential oils. On the stamens, there are also non-glandular trichomes, which play a role of pollen presenters. The nectary in the L. album flower has a shape of an irregular disc partly surrounding the base of the ovary. The content of sugars in the nectar was 43%. Sugar and honey yields per ha were calculated, and the values obtained were 153 kg and 191 kg, respectively.

8

The structure of septal nectaries and nectar presentation in the flowers of Allium aflatunense B. Fedtsch.

84%

Zuraw B., Weryszko-Chmielewska E., Laskowska H., Pogroszewska E.

Acta Agrobotanica

|

2009

|

tom 62

|

nr 2

The location and structure of the septal nectaries in the flowers of Allium aflatunense B. Fedtsch. were studied. Light and scanning electron microscopy were used for examination. It has been shown that the septal nectaries are located in the lower part of the ovary and in the gynophore on which the ovary is borne. Nectar is secreted through the single-layered epidermis surrounding three nectary slits and nectar release occurs through three openings located at the base of the gynophore, which are the outlets of the ducts connected to the nectary slits. The expanded and fused bases of the stamen filaments and the tepals participate in secondary nectar presentation. In the flowers of Allium aflatunense, numerous purple elements: tepals, filaments, style and pedicle, perform the role of a colour attractant. On the intensely green ovary, there occur glistening conical outgrowths of epidermal cells, which may also function as signal attractants.

9

The biology of flowering of winter aconite (Eranthis hyemalis (L.) Salisb.)

84%

Rysiak K., Zuraw b.

Acta Agrobotanica

|

2011

|

tom 64

|

nr 2

Eranthis hyemalis belongs to the Ranunculaceae family whose representatives enrich early spring pollen flow and nectar for pollinating insects. Flowering biology and morphological characteristics flowers of winter aconite were studied. The forage value was estimated as the rate of nectar production. Observations were carried out between 2008 and 2011 in the Botanical Garden of the Maria Curie-Skłodowska University located in the Lublin area. In the conditions of Lublin, flowering of winter aconite plants started at the beginning of February and lasted until the end of March. The seasonal bloom dynamics was strongly affected by maximum temperatures, which intensified flower blooming, and snowfalls which hampered this process. During the day, flowers opened between 8.00 am and 3.00 pm, but the highest intensity was between 10.00 am and 12.00 am. The process of pollen release, with the average number of 29 stamens shedding pollen in the flowers, lasted from 2 to 3 days. During the day the largest number of anthers opened at noon hours, between 11.00 am and 1.00 pm, though a certain rise in this number was also observed in the morning hours between 8.00 and 9.00 am. Eranthis hyemalis flowers develop funnel-shaped nectaries, on average 3-6 per flower. The determined amount of nectar per flower was 1.23 mg, while the concentration of sugars in it averaged 72.11%. The weight of nectar sugar per flower was 0.88 mg.

10

Characteristics of blooming, floral nectaries and nectar of Malus sargentii Rehd.

84%

Weryszko-Chmielewska E., Dmitruk M.

Acta Agrobotanica

|

2009

|

tom 62

|

nr 1

In the years 2007-2008, the flowering biology of Malus sargentii, an ornamental apple tree native to Japan, was studied in the conditions of Lublin (Poland). The daily rate of flower opening, flowering duration and flower visitation by insects were determined. The amount of nectar produced per flower and sugar content in the nectar were investigated. The size of nectaries and the micromorphology of their surface were examined using light and scanning electron microscopy. It was found that the greatest amount of flowers opened between 11.00 and 13.00. During this time, the largest number of insects was observed in the flowers. Bees (90%) were predominant among the insects, with a much smaller number of bumblebees (6%) and butterflies (4%). The flower life span was 5 days. Over this period, the flower produced, on the average, 0.71 mg of nectar with an average sugar content of 32%. The nectaries of Malus sargentii are orange-yellow coloured and they represent the hypanthial type. Due to the protrusion of the nectariferous tissue, they are classified as automorphic nectaries. The surface of the epidermal cells of the nectary was distinguished by distinct cuticle folds. A small number of stomata were located only in the basal part of the nectary. At the beginning of flowering, all stomata were closed, but secretion traces were observed near well-developed outer cuticular ledges.

11

The structure of the spur nectary in Dendrobium finisterrae Schltr. (Dendrobiinae, Orchidaceae)

84%

Kaminska M., Stpiczynska M.

Acta Agrobotanica

|

2011

|

tom 64

|

nr 1

To date, the structure of the nectary spur of Dendrobium finisterrae has not been studied in detail, and the present paper compares the structural organization of the floral nectary in this species with the spurs of other taxa. The nectary spur of D. finisterrae was examined by means of light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It is composed of a single layer of secretory epidermis and several layers of small and compactly arranged subepidermal secretory cells. The secretory cells have thick cellulosic cell walls with primary pits. The secretory tissue is supplied by vascular bundles that run beneath in ground parenchyma and are additionally surrounded by strands of sclerenchymatous fibers. The flowers of the investigated species displayed morphological features characteristic of bee-pollinated taxa, as they are zygomorphic, creamy-green coloured with evident nectar guides. They also emit a weak but nice scent. However, they possess some characters attributed to bird-pollinated flowers such as a short, massive nectary spur and collenchymatous secretory tissue that closely resembles the one found in the nectaries of certain species that are thought to be bird-pollinated. This similarity in anatomical organization of the nectary, regardless of geographical distribution and phylogeny, strongly indicates convergence and appears to be related to pollinator-driven selection.

12

Comparative floral morphology and anatomy of Gagea s. str. and Lloydia

84%

Novikov A.

Acta Agrobotanica

|

2021

|

tom 74

|

nr 1

13

Food plants of Apis mellifera in a nature reserve

84%

Hedtke C., Langer N.

Pszczelnicze Zeszyty Naukowe

|

1998

|

tom 42

|

nr 2

14

Carbonohydrate feeding of the tabanids [Diptera]

84%

Veselkin A.

Wiadomości Parazytologiczne

|

1998

|

tom 44

|

nr 3

15

The preliminary studies on flowering biology and melliferous value of three perennial species from Lamiaceae family

84%

Masierowska M., Krzysiak K.

Pszczelnicze Zeszyty Naukowe

|

2000

|

tom 44

|

nr 2

16

'Sweet but dangerous': nectaries in carnivorous plants

84%

Plachno B. J.

Acta Agrobotanica

|

2007

|

tom 60

|

nr 2

In carnivorous plants, two types of nectaries occur: extra- floral nectaries, generally associated with prey luring, and floral ones associated with pollination. Nectar produced by extra-floral nectaries not only attracts prey but may also be involved in trapping prey and plays a role in myrmecophily. The diversity of nectary structure in carnivorous plants reflects complicated evolutionary routes in this unique ecological group.

17

Fruit quality and processing potential in five new blackcurrant cultivars

84%

Siksnianas T., Stanys V., Sasnauskas A., Viskelis P., Rubinskiene M.

Journal of Fruit and Ornamental Plant Research

|

2006

|

tom 14

|

nr Suppl.2

18

Flowering, nectar production and insects visits in two cultivars of Cucurbita maxima Duch. flowers

84%

Dmitruk M.

Acta Agrobotanica

|

2008

|

tom 61

|

nr 1

The study was conducted on experimental plots in the conditions of Lublin. In the years 1998–2000 flowering, nectar secretion and insect visitation of male and female flowers of two winter squash (Cucurbita maxima Duch.) cultivars: ‘Ambar’ and ‘Amazonka’, were studied. The plants flowered from July to October. The flower life span was within the range of 7–10 hours. Female flowers of cv. Ambar were marked by the most abundant nectar secretion (129 mg). The nectar sugar content can be estimated as average (25%–35%). Winter squash nectar contained 84% of sucrose as well as 8–9% of fructose and 7%–8% of glucose. Flowers of the studied taxa were frequently foraged by the honey bee (66%–98% of total insects) and bumblebees (1%–30%).

19

Blooming and nectar secretion of Nepeta grandiflora Bieb. under the condition of lead excess

84%

Weryszko-Chmielewska E., Chwil M.

Journal of Apicultural Science

|

2002

|

tom 46

|

nr 1

20

The structure of some floral elements and the nectar production rate of Polemonium caeruleum L.

67%

Chwil M.

Acta Agrobotanica

|

2010

|

tom 63

|

nr 2

The present study, carried out in the period 2008 – 2009, covered some morphological and anatomical features of the flowers of Polemonium caeruleum L. and their nectar production rate in the climatic conditions of the Lublin region. Observations were made with stereoscopic, light and scanning electron microscopy. Nectar production in the flowers was determined using the pipette method. The flowers of Polemonium caeruleum develop a calyx covered by an epidermis with numerous non-glandular and glandular trichomes. The secretory trichomes are composed of a several-celled stalk and a four-celled head. At the boundary of the corolla tube and the lobes, there is white colouration with violet nectar guides. The epidermis in this region produces several-celled living trichomes that close the entry into the corolla tube, thereby protecting the nectar accumulated in it. These hairs are at the same time glistening colour attractants for insects. The tripartite stigma of the pistil is covered, from the adaxial side, by unicellular papillae with striated cuticular ornamentation, growing at high density. Around the ovary there is located a nectariferous disc, in the form of a free projection, which secrets nectar with sugar concentration of 29 – 52% and sugar weight ranging 1.1 – 1.8 mg/flower.

Ograniczanie wyników

Pyrrolizidine alkaloids in European honeys and honeys from overseas

Ecophysiological aspects of nectar reabsorption

Risk-taking and foraging strategy in honey bee workers collecting nectar and water

The effect of silicon on nectar and pollen production in Hosta Tratt. ‘Krossa Regal’

Nectary structure of Ornithidium sophronitis Rchb.f. (Orchidaceae: Maxillariinae)

Variability in nectar and pollen production in flowers of double-low lines of white mustard (Sinapis alba L.) and their attractiveness to honey bees

Adaptations of Lamium album L. flowers to pollination by Apoidea

The structure of septal nectaries and nectar presentation in the flowers of Allium aflatunense B. Fedtsch.

The biology of flowering of winter aconite (Eranthis hyemalis (L.) Salisb.)

Characteristics of blooming, floral nectaries and nectar of Malus sargentii Rehd.

The structure of the spur nectary in Dendrobium finisterrae Schltr. (Dendrobiinae, Orchidaceae)

Comparative floral morphology and anatomy of Gagea s. str. and Lloydia

Food plants of Apis mellifera in a nature reserve

Carbonohydrate feeding of the tabanids [Diptera]

The preliminary studies on flowering biology and melliferous value of three perennial species from Lamiaceae family

'Sweet but dangerous': nectaries in carnivorous plants

Fruit quality and processing potential in five new blackcurrant cultivars

Flowering, nectar production and insects visits in two cultivars of Cucurbita maxima Duch. flowers

Blooming and nectar secretion of Nepeta grandiflora Bieb. under the condition of lead excess

The structure of some floral elements and the nectar production rate of Polemonium caeruleum L.