Adaptation of male reproductive structures to wind pollination in gymnosperms: Cones and pollen grains

2011 ◽  
Vol 91 (5) ◽  
pp. 897-906 ◽  
Author(s):  
Y. Lu ◽  
B. Jin ◽  
L. Wang ◽  
Y. Wang ◽  
D. Wang ◽  
...  
Keyword(s):  
Pollen Dispersal ◽  
Digital Camera ◽  
Morphological Characteristics ◽  
Pollen Grains ◽  
Wind Pollination ◽  
Ancestral State ◽  
Physical Restraints ◽  
Pollination Success ◽  
Reproductive Structures ◽  
Evolutionary Response

Lu, Y., Jin, B., Wang, L., Wang, Y., Wang, D., Jiang, X.-X. and Chen, P. 2011. Adaptation of male reproductive structures to wind pollination in gymnosperms: Cones and pollen grains. Can. J. Plant Sci. 91: 897–906. Wind pollination (anemophily) in gymnosperms is thought to be an ancestral state. Previous studies considered wind pollination to be a largely random phenomenon, but recent evidence suggests that wind-pollinated species have evolved different complex reproductive adaptations for controlling and maximizing the success of wind pollination. However, compared with angiosperms, wind pollination in gymnosperms is poorly understood. We investigated the male reproductive structures of 13 representative gymnosperm species using a scanning electron microscope and digital camera, and analyzed how the morphological characteristics of male cones and pollen facilitate pollination. These characteristics showed a surprising variation between different gymnosperm species in improving pollination success. For example, the relationship between the position of the male cone and the surrounding vegetative structures is adjusted to optimize pollen release. The pollen grains have sacs and papilla and exhibit particular shapes after release from microsporangia, including boat-like, saccate, papilla-like and spheroid shapes, which facilitate pollen dispersal in the air. Taken together, our results suggest that the extensive diversity of male reproductive structures within gymnosperms represents an evolutionary response to long-term selection and results in solutions to the physical restraints of anemophily.

scholarly journals Morphology of Anemone sylvestris L. flower (Ranunculaceae)

2016 ◽  
Vol 75 (1) ◽  
pp. 74-80 ◽  
Author(s):  
Bożena Denisow ◽  
Sebastian Antoń ◽  
Małgorzata Wrzesień
Keyword(s):  
Seed Set ◽  
Pollen Dispersal ◽  
Pollen Grains ◽  
Starch Accumulation ◽  
Pollination Syndrome ◽  
Wind Pollination ◽  
Intermediate Form ◽  
Protected Species ◽  
Large Size ◽  
Opening And Closing

Abstract During the monitoring of populations of Anemone sylvestris L. (Ranunculaceae), a protected species in Poland, we found that the seed set is impaired. The flower is considered an adaptation that has coevolved to achieve effective pollination and successful fertilization. Therefore we have focused on the morphological and anatomical characteristics of the flowers of A. sylvestris L. as a prelude to the study of the species’ pollination biology and plant breeding system. The large size of the flower (50.6 ± 16.4 mm in dimensions) and its bowl shape fulfil both the biotic pollination syndrome and the aerodynamic requirements for pollen dispersal and capture. The opening and closing of the perianth provide a shelter for beetles. The odourless perianth, absence of nectar, scarcity of pollen (approximately 200 000 pollen grains per flower) and its traits - small size (axis P = 18.52 ± 1.0 μm; E = 16.59 ± 0.9 μm), lack of balsam on the exine surface, starch accumulation in more than 95% of pollen grains correspond to the specialization in anemophily. The stigma is papillous, the dense hairs are situated between single carpels indicating adaptation to capturing dry pollen and specialization in the wind pollination syndrome. The flower of A. sylvestris is an example for an intermediate form between entomophily and anemophily, i.e. a secondary and more advanced feature among Ranunculaceae.

scholarly journals Monoicy in A. angustifolia (Bert.) O. Kuntze (Araucariaceae): I. Morphological aspects of the reproductive structures

2009 ◽  
Vol 81 (4) ◽  
pp. 701-705 ◽  
Author(s):  
Valdir M. Stefenon ◽  
Clarissa A. Caprestano
Keyword(s):  
Morphological Characteristics ◽  
Pollen Grains ◽  
Rare Occurrence ◽  
Araucaria Angustifolia ◽  
Conifer Species ◽  
Normal Morphology ◽  
Male And Female ◽  
Reproductive Structures ◽  
Morphological Aspects ◽  
Adult Trees

Araucaria angustifolia (Bert.) O. Kuntze is a dioecious conifer species native of Brazil. The rare occurrence of monoiceous specimens have been attributed to pathogenic infections or other injuries in adult trees. Here, the morphological characteristics of male and female cones and pollen grains of a monoiceous A. angustifolia are described. Male and female cones and pollen grains presented normal morphology, lacking any sort of injuries or infection and suggesting the existence of further grounds for the occurrence of monoicy in this conifer species.

Insects facilitate wind pollination in pollen-limited Crateva adansonii (Capparaceae)

2011 ◽  
Vol 59 (1) ◽  
pp. 61 ◽  
Author(s):  
Yash Mangla ◽  
Rajesh Tandon
Keyword(s):  
Fruit Set ◽  
Pollen Limitation ◽  
Airborne Pollen ◽  
Pollen Dispersal ◽  
Natural Populations ◽  
Pollen Grains ◽  
Floral Biology ◽  
Wind Pollination ◽  
Reproductive Assurance

Low fruit-set in obligately outbreeding plant species is attributed to a variety of reasons that can be ascertained from reproductive studies. In the present work, the causes of poor natural fruit-set in Crateva adansonii DC. were investigated. Floral biology, the role of wind and insects in pollination and the breeding system of the species were studied in two natural populations for three consecutive seasons (2006–08). The flowers exhibited traits conducive to a mixture of wind and insect pollination (ambophily). Although a variety of insects visited the flowers, they were ineffective in pollinating. Nevertheless, active foraging by the honeybees (Apis dorsata, A. mellifera and A. cerana indica) facilitated enhanced pollen dispersal in the air and resulted in indirect pollination by wind. Airborne pollen grains pollinated the plants only up to 10 m. Fruit-set from open pollination was comparable to wind-pollinated flowers. Supplemental pollination treatments established the occurrence of strong self-incompatibility (SI) (index of SI = 0.14). Spontaneous autogamy was prevented by pronounced herkogamy. Low natural fecundity in C. adansonii is due to pollination failure, pollen limitation (pollen limitation index = 0.98) and the sparse distribution of the conspecifics; partial SI may partly ensure reproductive assurance through geitonogamy. In the absence of a pollinator wind appears to act as a secondary mode of pollination.

Molecular Mechanisms of Pollination Biology

2020 ◽  
Vol 71 (1) ◽  
pp. 487-515 ◽  
Author(s):  
Róisín Fattorini ◽  
Beverley J. Glover
Keyword(s):  
Molecular Mechanisms ◽  
Pollen Grains ◽  
Flowering Plants ◽  
Wind Pollination ◽  
Developmental Studies ◽  
Essential Requirement ◽  
Pollination Success ◽  
Diverse Species ◽  
To Come ◽  
Effective Use

Pollination is the transfer of pollen grains from the stamens to the stigma, an essential requirement of sexual reproduction in flowering plants. Cross-pollination increases genetic diversity and is favored by selection in the majority of situations. Flowering plants have evolved a wide variety of traits that influence pollination success, including those involved in optimization of self-pollination, attraction of animal pollinators, and the effective use of wind pollination. In this review we discuss our current understanding of the molecular basis of the development and production of these various traits. We conclude that recent integration of molecular developmental studies with population genetic approaches is improving our understanding of how selection acts on key floral traits in taxonomically diverse species, and that further work in nonmodel systems promises to provide exciting insights in the years to come.

scholarly journals Morphological characteristic of black-winged myna (acridotheres melanopterus)*

2018 ◽  
Vol 197 ◽  
pp. 06006 ◽  
Author(s):  
Renaldi Ednin Vernia ◽  
Anais Tritto ◽  
Abinawanto Abinawanto ◽  
Nurul Winarni ◽  
Anita mayasari ◽  
...  
Keyword(s):  
Morphological Characteristic ◽  
Sample Selection ◽  
Digital Camera ◽  
Morphological Characteristics ◽  
The Body ◽  
Entire Body ◽  
Body Parts ◽  
Breeding Management ◽  
Black Feather ◽  
Average Body

Black-winged myna (Acridotheres melanopterus) is an endemic bird of Java and Bali, currently critically endangered based on International Union of Conservation for Nature (IUCN) since 2010. The study about black-winged myna morphological characteristic is important because it has two relatives with almost identical features of morphology. The information can be used as a basis in breeding management to avoid hybridization. The study aims to determine the morphological characteristics of black-winged myna. The sample selection was done using purposive sampling method. Data was taken from 36 black-winged mynas with >=2 years old. Data collection was done by measuring and documenting every morphological feature of the observed body parts. Documentation of the wings, back, chest, head and sides of the body are taken from each bird using a digital camera. The results showed that almost the entire body of black-winged myna covered by white feather, black feather only present on the cover of the wings and tail. Black eyes surrounded by yellow skin without feather. The beak is orange with blackish parts around the nostrils. The bird has yellow legs with three fingers at the front and one finger at the back. The average body length of this bird is 22.5 cm, weight 89.02 g, width 5.98 cm, body circumference 14.36 cm and wingspan 38.49 cm.

scholarly journals Why so many flowers? A preliminary assessment of mixed pollination strategy enhancing sexual reproduction of the invasive <i>Acacia longifolia</i> in Portugal

Web Ecology ◽  
2018 ◽  
Vol 18 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Manuela Giovanetti ◽  
Margarida Ramos ◽  
Cristina Máguas
Keyword(s):  
Invasive Plant ◽  
Seed Set ◽  
Pollen Grains ◽  
Striking Difference ◽  
Pollination Syndromes ◽  
Pollination Success ◽  
Relative Contribution ◽  
Acacia Longifolia ◽  
Exclusion Experiments ◽  
Pollination Strategy

Abstract. Acacia longifolia, a native legume from Australia, has been introduced in many European countries and elsewhere, thus becoming one of the most important global invasive species. In Europe, its flowering occurs in a period unsuitable for insect activity: nonetheless it is considered entomophilous. Floral traits of this species are puzzling: brightly coloured and scented as liked by insects, but with abundant staminate small-sized flowers and relatively small pollen grains, as it is common in anemophilous species. Invasion processes are especially favoured when reshaping local ecological networks, thus the interest in understanding pollination syndromes associated with invasive plant species that may facilitate invasiveness. Moreover, a striking difference exists between its massive flowering and relatively poor seed set. We introduced a novel approach: first, we consider the possibility that a part of the pollination success is carried on by wind and, second, we weighted the ethological perspective of the main pollinator. During the flowering season of A. longifolia (February–April 2016), we carried on exclusion experiments to detect the relative contribution of insects and wind. While the exclusion experiments corroborated the need for pollen vectors, we actually recorded a low abundance of insects. The honeybee, known pollinator of acacias, was relatively rare and not always productive in terms of successful visits. While wind contributed to seed set, focal observations confirmed that honeybees transfer pollen when visiting both the inflorescences to collect pollen and the extrafloral nectaries to collect nectar. The mixed pollination strategy of A. longifolia may then be the basis of its success in invading Portugal's windy coasts.

scholarly journals Floral Biology and Seed Production in Cultivated North American Ginseng (Panax quinquefolius)

2000 ◽  
Vol 125 (5) ◽  
pp. 567-575 ◽  
Author(s):  
Cayetana Schluter ◽  
Zamir K. Punja
Keyword(s):  
Seed Production ◽  
North American ◽  
Age Groups ◽  
Morphological Characteristics ◽  
Floral Biology ◽  
American Ginseng ◽  
Panax Quinquefolius ◽  
Flowering Period ◽  
Pollination Success ◽  
Pollen Release

Morphological characteristics of flowers, duration of flowering, degree of self-pollination, and extent of berry and seed production in North American ginseng (Panax quinquefolius L.) were studied under controlled environmental conditions as well as under field conditions. A comparison was also made between plants of 3 and 4 years of age at two field locations. The duration of flowering was ≈4 weeks and was similar in plants of both age groups grown in the two environments; however, 4-year-old plants produced an average of 40% more flowers (≈100 per plant in total) compared to 3-year-old plants. Flowers were comprised of five greenish-colored petals, five stamens, and an inferior ovary consisting of predominantly two fused carpels and stigmatic lobes. Anthers dehisced in staggered succession within individual flowers, and flowering began with the outermost edge of the umbel and proceeded inwards. At any given time during the 4-week flowering period, ≈10% of the flowers in an umbel had recently opened and were producing pollen. Stigma receptivity was associated with separation of the stigmatic lobes; this occurred at some time after pollen release. Growth of pollen tubes through the style in naturally pollinated flowers was most evident when the stigmatic lobes had separated. The proportion of flowers that developed into mature berries (pollination success rate) was in the range of 41% to 68% for both 3-year-old and 4-year-old plants. However, when the inflorescence was bagged during the flowering period, berry formation was increased by 13% to 21% in 4-year-old plants, depending on location. A majority of the berries (92% to 99%) contained one or two seeds in an almost equal frequency, with the remaining berries containing three seeds. In 4-year-old plants, the frequency of two-seeded berries was increased by ≈13% by bagging the inflorescence. These observations indicate that P. quinquefolius is highly self-fertile and that several physiological and environmental factors can affect seed production.

scholarly journals SCDMImage: um aplicativo para detecção de características morfológicas em produtos agrícolas

2021 ◽  
Vol 1 (53) ◽  
pp. 27
Author(s):  
Valnyr Vasconcelos Lira ◽  
Francisco Fechine Borges ◽  
Jéssica Cordeiro da Silva Santos ◽  
Antônio Pedro Gomes Tabosa ◽  
Mário Eduardo Rangel Moreira Cavalcanti Mata
Keyword(s):  
Fruits And Vegetables ◽  
Mangifera Indica ◽  
Digital Camera ◽  
Morphological Characteristics ◽  
Reliable Estimate ◽  
Continuous Growth ◽  
The Masses ◽  
Cultivation Techniques

<p><span class="fontstyle0">With the evolution of cultivation techniques, the world production of fruits and vegetables has been presenting a continuous growth. Despite the increase in production, a significant portion of the harvested products is mainly lost in the post-harvest due to several factors, such as inapropriate handling, transportation and conservation, lack of selection and classification, poorly sized packaging, among others. In general, the quality of fruits and vegetables is usually evaluated by the following parameters: size, shape, mass, color, firmness, ripeness, absence of bruises and pathologies.The objective of this work was to develop an application in Matlab to detect morphological characteristics (width, length, area, perimeter) of Mangifera indica L., ‘Tommy Atkins’ mangos from images, and using the same images, estimate its weigth. The images of the mangoes were acquired with a digital camera attached to an illuminated box and later processed in an application developed in Matlab. The images showed the morphological characteristics of the samples were obtained and an equation was determined to estimate their mass. The determination of the mass from the images had a 96% correlation with the actual mass measured with a scale and it was possible to obtain a reliable estimate of the masses of the mangoes from their images.</span></p>

Pollen biodiversity – why are pollen grains different despite having the same function? A review

2020 ◽  
Vol 193 (2) ◽  
pp. 141-164 ◽  
Author(s):  
Ettore Pacini ◽  
Gian Gabriele Franchi
Keyword(s):  
Pollen Dispersal ◽  
Pollen Grains ◽  
Reproductive Function ◽  
Female Competition ◽  
Size Number ◽  
Pollen Presentation ◽  
Dispersal Unit ◽  
Number Of Cells ◽  
Physiological Characters ◽  
Female Counterpart

Abstract The main morphological, cytological and physiological characters of ripe pollen are described, compared, analysed and discussed individually, in multiple combinations and in respect to the female counterpart and the biotic and abiotic components of the environment. This is to try to understand the reasons why pollen grains have the same reproductive function, but at dispersal are morphologically and physiologically different in many respects. The considered characters are: one or more types of grain per species; shape and size; number of cells; types of pollen dispersal unit; sporoderm stratification, furrows, colpori and other kinds of apertures; pollen presentation and array; water content percentage; and mature pollen reserves and osmotics. Some of the pollen features are correlated between themselves, some with the female counterpart or male and female competition, and others with the different components of the environment where the species lives, when it flowers and when pollen presentation occurs.

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