Reproductive Function in the Mimosoid Legume Acacia retinodes: Ultrastructural and Cytochemical Characteristics of Stigma Receptivity

1989 ◽  
Vol 37 (2) ◽  
pp. 103 ◽  
Author(s):  
RB Knox ◽  
J Kenrick ◽  
S Jobson ◽  
C Dumas
Keyword(s):  
Fatty Acids ◽  
Reproductive Function ◽  
Stigma Receptivity ◽  
Flower Opening ◽  
Flavonoid Aglycones ◽  
Browning Reaction ◽  
Female Phase ◽  
Male Phase ◽  
The Moment ◽  
Stigma Exudate

The stigma of Acacia retinodes is receptive from the moment the flower opens (female phase). Receptivity, assessed in terms of pod set, is highest at flower opening, and lowest the following day (male phase). Stigma receptivity is associated with the acquisition of a heterogeneous stigma exudate, the components of which are secreted sequentially during differentiation. Cytochemical probes have tentatively identified the principal components as unsaturated and saturated lipids, free fatty acids, flavonoid aglycones, carbohydrates, proteins and phenolic compounds. The onset of male phase in unpollinated stigmas is associated with a breakdown of the plasma membrane and organelle membranes of stigma cells, and subsequently a browning reaction.

Thermogenesis in Syngonium (Araceae)

2007 ◽  
Vol 85 (2) ◽  
pp. 184-190 ◽  
Author(s):  
Mathieu Chouteau ◽  
Denis Barabé ◽  
Marc Gibernau
Keyword(s):  
Heat Production ◽  
Stigma Receptivity ◽  
The Third ◽  
Female Phase ◽  
Male Phase

Floral cycles and spadix temperatures were recorded for two species of Syngonium: Syngonium schottianum Wendl. ex Schott (section Cordatum) and Syngonium angustatum Schott (section Syngonium). Both species exhibited a 3-day flowering cycle, beginning with stigma receptivity and opening of the spathe the first day, the female phase continues over the second day, and the male phase continues over the third day. These species displayed two distinct patterns of heat production during flowering. In S. schottianum, the spadix warmed up twice during the beginning of the second and third nights, but in S. angustatum, the spadix warmed up twice the second day, once the second night, and once the third day. These different thermogenic cycles are discussed in regard to other genera that are phylogenetically close or sharing similar flowering and thermogenic cycles.

scholarly journals Nocturnal and diurnal pollination in Copaifera coriacea, a dominant species in sand dunes of the Middle São Francisco River Basin, Northeastern Brazil

2021 ◽  
Vol 154 (2) ◽  
pp. 207-216
Author(s):  
Isys Mascarenhas Souza ◽  
Frederic Mendes Hughes ◽  
Ligia Silveira Funch ◽  
Luciano Paganucci de Queiroz
Keyword(s):  
Uv Light ◽  
Pollen Viability ◽  
Sand Dunes ◽  
Abundant Species ◽  
Pollen Tubes ◽  
Northeastern Brazil ◽  
Stigma Receptivity ◽  
Flower Opening ◽  
Pollination System ◽  
Floral Visitors

Background and aims – Copaifera coriacea, a species in the resin-producing clade Detarioideae (Leguminosae), is an endemic and abundant species found in sand dunes in Brazilian Caatinga domain vegetation – a Quaternary paleodesert. We investigated floral traits and aspects of pollination biology, focusing on the pollination system of C. coriacea. Material and methods – Anthesis duration, stigma receptivity, pollen viability, nectar concentration, and the presence of osmophores and pigments reflecting UV light were assessed. Floral visitors were classified as potential pollinators, occasional pollinators or thieves, based on the time and foraging behaviour and resource collected. Pollination effectiveness were assessed for potential pollinators by the detection of pollen tubes on the stigma or stylar canal by epifluorescence microscopy.Key results – The species has white and small flowers, with anthesis beginning in the dark (ca 00:30) and the flowers are completely opened approximately 3 h later, when a sweet odour is perceptible. The onset of stigma receptivity and pollen grain viability occurs only after the completion of flower opening, and a concentrated nectar is available during the day. The presence of pollen tubes confirmed the efficiency of the main insects in the transfer of pollen. Conclusion – Our result demonstrates that C. coriacea has a generalist pollination system mediated mainly by two distinct guilds of insect pollinators: moths (nocturnal, searching for nectar) and bees (diurnal, pollen collectors). This finding can provide more information about diversification in the genus Copaifera.

Pollination of Amorphophallus johnsonii (Araceae) by carrion beetles (Phaeochrous amplus) in a Ghanaian rain forest

1996 ◽  
Vol 12 (3) ◽  
pp. 409-418 ◽  
Author(s):  
Daniel D. N. Beath
Keyword(s):  
Rain Forest ◽  
Rainy Season ◽  
Male Inflorescence ◽  
Large Numbers ◽  
Female Phase ◽  
Male Phase ◽  
Carrion Beetles ◽  
Main Rainy Season

ABSTRACTAmorphophallus johnsonii (N. E. Brown) flowers during April in the main rainy season in Ghana. Anthesis starts at dusk with fluid oozing from the upper spadix accompanied by a strong aminoid odour. Just after dark large numbers of carrion beetles (Phaeochrous amplus) and occasional dung fly species (Hemigymnochaeta unicolor and Paryphodes tigrinus) visit the inflorescences. The beetles become trapped in the lower spathe overnight and remain in the spadix until the following evening. Between 1630 and 1645 h the following day, the anthers produce long threads of sticky pollen. The trapped beetles escape just after dark by crawling up the spadix, past the dehisced anthers and fly away from the spadix tip. Marked beetles were seen to transfer pollen from male phase to female phase inflorescences. Successful fertilisation was only effected if pollen was transferred on the same night from a male inflorescence 30 m or less away. Pollen is psilate and typical of beetle pollinated Araceae. Berries ripen approximately 70 d after fertilization and ripen basisetally in the infructescence.

Improving the Productivity of Avocado Seed for Create High Value Products

2019 ◽  
Vol 394 ◽  
pp. 47-54
Author(s):  
Gerardo Espinosa-Garza ◽  
Imelda de Jesús Loera-Hernández ◽  
Jacobo Tijerina Aguilera
Keyword(s):  
Fatty Acids ◽  
Raw Material ◽  
Organic Load ◽  
Bioactive Substances ◽  
Cholesterol Levels ◽  
Therapeutic Properties ◽  
Processed Form ◽  
The Moment ◽  
Vegetables And Fruits ◽  
Avocado Seed

Nowadays there is a significant increase in the consumption of vegetables and fruits, due toall the therapeutic properties that have been associated with them, some of these fruits and vegetablesare consumed in processed form [1]. During the process, byproducts such as husks and seeds aregenerated, which are usually difficult to handle waste since they have a high organic load and carryan additional cost for their treatment [2]. Proteins, carbohydrates, bioactive substances, essential oils,are some of the compounds that can be found in this type of waste [3-6]. The subproduct mentionedcan be used as raw material for obtaining other products of high value for consumption. The objectiveof the present investigation was to determine the concentration of various minerals, fatty acids,resveratrol and phytosterols present in the avocado seed in order to add value to this residue. Afterconducting all these experiments in the laboratory, it was shown that the avocado seed containsresveratrol and other components that help improve glucose and cholesterol levels. An avocado seedsupplement was obtained that has been tested with rabbits for the moment.

Effects of calcium salts of fatty acids on follicular characteristics and several blood parameters in two fat-tailed sheep breeds

2002 ◽  
Vol 2002 ◽  
pp. 131-131
Author(s):  
M. J. Zamiri ◽  
E. Rowghani ◽  
S. M. Ghoreishi
Keyword(s):  
Fatty Acids ◽  
Plasma Cholesterol ◽  
Post Partum ◽  
Reproductive Function ◽  
Blood Parameters ◽  
Dietary Lipid ◽  
Ovarian Activity ◽  
Corpora Lutea ◽  
Luteal Function ◽  
Sheep Breeds

There is substantial evidence that the increased consumption of fat by dairy cattle can result in an increase in the number ovarian follicles, and the number and size of corpora lutea; it also stimulates post-partum ovarian activity and improve pregnancy rate. Increased dietary lipid also increases plasma cholesterol and progesterone, and the supply of lipoproteins which play significant roles in regulating ovarian steroidogenesis (Willimas, 1996). In contrast to cattle, there are few observations on the effects of dietary lipid on reproductive function in sheep. Intravascular infusion of lipid into ewes stimulated progesterone and prostaglandin synthesis (Burke et al., 1996), and dietary supplementation of calcium soaps of fatty acids enhanced luteal function (Kuran et al., 1999). Calcium soaps of fatty acids have been manufactured in Iran in recent years and sold under the trade name of Megalac. The aim of the present experiment was to study the effects of this protected fat on follicular number and luteal activity in two fat-tailed sheep breeds.

scholarly journals Male flowers of Aconitum compensate for toxic pollen with increased floral signals and rewards for pollinators

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
A.-L. Jacquemart ◽  
C. Buyens ◽  
M.-F. Hérent ◽  
J. Quetin-Leclercq ◽  
G. Lognay ◽  
...  
Keyword(s):  
Larval Food ◽  
Chemical Defences ◽  
Toxic Nectar ◽  
Pollen Transfer Efficiency ◽  
Aconitum Napellus ◽  
Female Phase ◽  
Male Phase ◽  
Male Flowers ◽  
Nectar Rewards ◽  
Toxic Pollen

Abstract Many plants require animal pollinators for successful reproduction; these plants provide pollinator resources in pollen and nectar (rewards) and attract pollinators by specific cues (signals). In a seeming contradiction, some plants produce toxins such as alkaloids in their pollen and nectar, protecting their resources from ineffective pollinators. We investigated signals and rewards in the toxic, protandrous bee-pollinated plant Aconitum napellus, hypothesizing that male-phase flower reproductive success is pollinator-limited, which should favour higher levels of signals (odours) and rewards (nectar and pollen) compared with female-phase flowers. Furthermore, we expected insect visitors to forage only for nectar, due to the toxicity of pollen. We demonstrated that male-phase flowers emitted more volatile molecules and produced higher volumes of nectar than female-phase flowers. Alkaloids in pollen functioned as chemical defences, and were more diverse and more concentrated compared to the alkaloids in nectar. Visitors actively collected little pollen for larval food but consumed more of the less-toxic nectar. Toxic pollen remaining on the bee bodies promoted pollen transfer efficiency, facilitating pollination.

scholarly journals Linking pollinator efficiency to patterns of pollen limitation: small bees exploit the plant–pollinator mutualism

2018 ◽  
Vol 285 (1880) ◽  
pp. 20180635 ◽  
Author(s):  
Matthew H. Koski ◽  
Jennifer L. Ison ◽  
Ashley Padilla ◽  
Angela Q. Pham ◽  
Laura F. Galloway
Keyword(s):  
Pollen Limitation ◽  
Pollen Deposition ◽  
Pollinator Efficiency ◽  
Flower Visitation ◽  
Female Phase ◽  
Male Phase ◽  
Single Flower ◽  
Floral Visitation ◽  
Low Efficiency ◽  
Plant Pollinator

Seemingly mutualistic relationships can be exploited, in some cases reducing fitness of the exploited species. In plants, the insufficient receipt of pollen limits reproduction. While infrequent pollination commonly underlies pollen limitation (PL), frequent interactions with low-efficiency, exploitative pollinators may also cause PL. In the widespread protandrous herb Campanula americana , visitation by three pollinators explained 63% of the variation in PL among populations spanning the range. Bumblebees and the medium-sized Megachile campanulae enhanced reproductive success, but small solitary bees exacerbated PL. To dissect mechanisms behind these relationships, we scored sex-specific floral visitation, and the contributions of each pollinator to plant fitness using single flower visits. Small bees and M. campanulae overvisited male-phase flowers, but bumblebees frequently visited female-phase flowers. Fewer bumblebee visits were required to saturate seed set compared to other bees. Scaling pollinator efficiency metrics to populations, small bees deplete large amounts of pollen due to highly male-biased flower visitation and infrequent pollen deposition. Thus, small bees reduce plant reproduction by limiting pollen available for transfer by efficient pollinators, and appear to exploit the plant–pollinator mutualism, acting as functional parasites to C. americana . It is therefore unlikely that small bees will compensate for reproductive failure in C. americana when bumblebees are scarce.

scholarly journals Intraspecific Seasonal Variation of Flowering Synchronization in a Heterodichogamous Tree

Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1509
Author(s):  
Noemi Tel-Zur ◽  
Tamar Keasar
Keyword(s):  
Genetic Diversity ◽  
Seasonal Variation ◽  
Phase Duration ◽  
Male And Female ◽  
Flowering Synchrony ◽  
Flowering Season ◽  
Hand Pollination ◽  
Female Phase ◽  
Male Phase ◽  
Phase Differences

Heterodichogamous reproduction in plants involves two flowering morphs, reciprocal in their timing of male and female sexual functions. The degree of synchrony in floral sex phase, within and between individuals of each morph, determines the flowers’ potential fertilization partners. Complete within-morph synchrony enables across-morph mating alone, whereas unsynchronized floral sex phases may allow fertilization within a plant individual (geitonogamy) or within a morph. We documented the disruption of flowering synchrony in the heterodichogamous Ziziphus spina-christi towards the end of its seven-month flowering season. This desert tree has self-incompatible, protandrous, short-lived (2-day) flowers that open before dawn (‘Early’ morph) or around noon (‘Late’ morph). We counted flowers in the male and female phase on flowering branches that were sampled monthly during the 2016–2018 flowering seasons. In 2018, we also tagged flowers and followed their sex-phase distributions over two days at the start, middle, and end of the season. The switch to the female phase was delayed at the end-season (November-December), and 74% of the flowers did not develop beyond their male phase. Differences in male-phase duration resulted in asynchrony among flowers within each tree and among trees of both flowering morphs. Consequently, fertilization between trees of the same morph becomes potentially possible during the end-season. In controlled hand-pollination assays, some within-morph fertilizations set fruit. The end-season breakdown of synchronous flowering generates variability within morphs and populations. We suggest that this variability may potentially enable new mating combinations in a population and enhance its genetic diversity.

scholarly journals Stigma receptivity in Cashew nut (Anacardium occidentale L.)

2020 ◽  
Vol 21 ◽  
pp. 37-39
Author(s):  
Swapan Mandal ◽  
Keyword(s):  
Experimental Study ◽  
Research Centre ◽  
Research Station ◽  
Regional Research ◽  
Stigma Receptivity ◽  
Flower Opening ◽  
Cashew Nut ◽  
Monoecious Plant ◽  
Optimum Period ◽  
And Bisexual

The cashew is widely and commercially cultivated throughout the nation for its nut. Cashew is a polygamo – monoecious plant with both male and bisexual flowers developing in same inflorescence. Experimental study was conducted at Kesiary Cashew Plantation Sector, Medinipur as per the guidelines Regional Research Station, Jhargram and National Research Centre of Cashew, Karnataka (2014 – 2018). Changes in stigma receptivity were studied by over 100 panicles chosen at random taken from the commercially cultivated germplasms (WBDC – 4, Kottakerala – 2/97, Dicherla – 2/9, Vetore – 56 and Ullal – 2). The study was continued as for one day before, on the day of flower opening, one day & two days after flowering. It indicates that one day prior to opening & two days after of flowering, stigma receptivity was maximum in the plants of Vetore – 56. But on the day & one day after of flowering it was highest in Dicherla – 2/9. The optimum period of receptivity was at 12 noon on the day of anthesis.

Sign in / Sign up

Export Citation Format

Share Document