scholarly journals In vivo and in vitro pollen maturation in Lilium: influence of carbohydrates

2014 ◽  
Vol 65 (1-2) ◽  
pp. 73-82 ◽  
Author(s):  
Christophe Clement ◽  
Daniel Al-Awad ◽  
Jean C. Audran
Keyword(s):  
Germination Rate ◽  
Starch Synthesis ◽  
Pollen Grains ◽  
Second Phase ◽  
Flower Buds ◽  
Flower Bud ◽  
Pollen Maturation ◽  
Microspore Stage

The purpose of this study was to develop a protocol for <em>in vitro</em> conform pollen maturation, as a model to study the involvement of carbohydrates on pollen maturation in <em>Lilium</em>. <em>In vivo</em> and <em>in vitro</em> pollen maturations were followed and compared by transmission electron microscopy, and several <em>in vitro</em> parameters were tested in terms of carbohydrate physiology. <em>In vivo</em>, pollen maturation was initiated at the vacuolated microspore stage, and consisted of two successive phases. The first phase was characterized by reactivation of microspore organelles, followed by microspore mitosis, starch synthesis and vacuole breakdown. During the second phase, starch was progressively degraded whereas lipid and phytine reserves accumulated. <em>In vivo</em>, pollen maturation occured within 14 days and pollen germination rate was 73.6 ± 2.2%. We then attempted to realise <em>in vitro</em> pollen maturation starting from the vacuolated microspore stage. The best results were obtained with flower buds cultivated at 26<sup>o</sup>C, in 100 µmol/m<sup>2</sup>/s light, with a 16h/8h photoperiod on a modified Heller's medium supplemented with NAA (10<sup>-2</sup> mg/l) and sucrose (M/6). In these conditions, pollen maturation occured within 7 days only. <em>In vitro</em> matured pollen is cytologically comparable to <em>in vivo</em> developed pollen grains and the germination rate was 72.4 ± 3.7%. When flower buds were cultivated in the dark, the germination rate decreased, but this could be compensated by providing high sucrose concentrations (1M) in the medium. Further, photosynthesis inhibitors had the same effect on pollen maturation than the darkness, strongly suggesting that photosynthesis occurs in the flower bud and is important for pollen maturation in <em>Lilium</em>.

scholarly journals Anatomical Characteristics of Petalized Anther Abortion in Male Sterile Camellia oleifera Plants

2021 ◽  
pp. 1-13
Author(s):  
Yang Hu ◽  
Chao Gao ◽  
Quanen Deng ◽  
Jie Qiu ◽  
Hongli Wei ◽  
...  
Keyword(s):  
Germination Rate ◽  
Pollen Grains ◽  
Relative Activity ◽  
Control Group ◽  
Camellia Oleifera ◽  
Male Sterile ◽  
Flower Bud ◽  
Triphenyltetrazolium Chloride ◽  
Pollen Sacs

Petalized anther abortion is an important characteristic of male sterility in plants. The male sterile plants (HB-21) evincing petalized anther abortion previously discovered in a clone population of the Camellia oleifera cultivar Huashuo by our research group were selected as the experimental material in this study. Using plant microscopy and anatomic methods and given the correspondence between external morphology and internal structure, we studied the anatomic characteristics of petalized anther abortion (with a fertile plant as the control group) in various stages, from flower bud differentiation to anther maturity, in hopes of providing a theoretical basis for research on and applications of male sterile C. oleifera plants, a new method for the selection of male sterile C. oleifera cultivars, and improvements in the yield and quality of C. oleifera. In this study, the development of anthers in C. oleifera was divided into 14 stages. Petalized anther abortion in male sterile plants was mainly initiated in the second stage (the stage of sporogenous cells). Either the petalized upper anther parts did not form pollen sacs, or the entire anthers did not form pollen sacs. The lower parts of some anthers could form deformed pollen sacs and develop, and these anthers could be roughly divided into two types: fully and partially petalized anthers. Abnormal callose and the premature degradation of the tapetum occurred in the pollen sacs formed by partially petalized anthers during the development process, resulting in the absence of inclusions in the pollen grains formed. Small quantities of mature pollen grains withered inward from the germinal furrows, exhibiting obvious abortion characteristics. The relative in vitro germination rate of the pollen produced by the partially petalized anthers of sterile plants was 11.20%, and the relative activity of triphenyltetrazolium chloride was 3.24%, while the fully petalized anthers did not generate pollen grains. Either the petalized anthers in male sterile plants did not produce pollen, or the vitality of the small amounts of pollen produced by sterile plants was very low compared with that of fertile plants. Such male sterile plants could be used to select correct clones and have good prospects for application in production.

scholarly journals Embryological studies of reciprocal crosses between Vicia faba and Vicia narbonensis

2014 ◽  
Vol 67 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Maciej Zenkteler ◽  
Mechtild Tegeder ◽  
Otto Schieder
Keyword(s):  
Vicia Faba ◽  
Pollen Grains ◽  
Pollen Tubes ◽  
Flower Buds ◽  
Reciprocal Crosses ◽  
Globular Embryos ◽  
Vicia Narbonensis ◽  
Whole Number

A study was undertaken to asses the reciprocal crossability between <em>Vicia faba</em> and <em>Vicia narbonensis</em>. Flower buds or only ovaries of several varietes and genotypes were cross-pollinated in vivo (green house and field) and in vitro. Only few pollen tubes passed the style and entered into the ovary. On the whole number of 5320 cross pollinated in vivo and in vitro flowers and ovaries of <em>Vicia narbonensis</em> only 78 globular hybrid embryos were observed. After cross pollination in vivo of 3860 flower buds and ovaries of <em>Vicia faba</em> globular embryos developed in 124 ovules. The highest number of globular embryos were obtained when the <em>Vicia faba</em> line 1/33 was pollinated with <em>Vicia narbonensis</em> lines P3, P5, 150, SE.Embryogenesis proceeded till the 6-10 day after pollination, however, karyological disturbances in the cells of embryos and endosperm were often noticed at earlier stages. In vitro pollen grains of <em>Vicia faba</em> germinated on stigmas and ovaries of <em>Vicia narbonensis</em>, a significant increase in the growth of pollen tubes was noticed after ovary pollination. The technique of in vitro pollination was not suitable for <em>Vicia faba</em> as the inoculated explants died shortly after transferring onto the medium. The results indicate that finding a more suitable genotype for crossing may give a chance to obtain higher number of embryos (example line 1/33) - thus sufficient number for culturing them on media.

Identification and quantification of polyphenols from Cassia auriculata L. leaf, flower and flower bud using UPLC-QqQ-MS/MS

2021 ◽  
pp. 1-9
Author(s):  
Devanesan Arul Ananth ◽  
Vijayaraghavan Mahalakshmi ◽  
Thilagar Sivasudha ◽  
Liron Klipcan ◽  
Zipora Tietel
Keyword(s):  
Phenolic Compounds ◽  
Hydroxycinnamic Acids ◽  
Benzoic Acids ◽  
Flower Buds ◽  
Flower Bud ◽  
Plant Parts ◽  
Cassia Auriculata ◽  
Polyphenolic Composition

Abstract Cassia auriculata is an Ayurvedic medicinal herb, traditionally indicated for diabetes and hyperlipidemia. Several works have demonstrated its antioxidant, antidiabetic and anti-hyperlipidemic activity in vivo and in vitro. Nevertheless, only a few works have investigated its phytochemical composition, and specifically, the polyphenolic composition of the various plant parts that are traditionally used. In this work, the polyphenolic composition of C. auriculata leaves, flowers and flower buds were evaluated using UPLC-QqQ-MS/MS. Our results demonstrated the polyphenolic profile of C. auriculata plant parts. A total of five benzoic acids, four hydroxycinnamic acids, three flavonoids and two other phenolic compounds were identified and quantified. Our results show that in C. auriculata leaves, flavonoids were most abundant (4204 µg/g DW), while in flowers benzoic acids were the most prominent (3924 µg/g DW). Total benzoic acid contents ranged from 1580 to 3924 µg/g DW in leaf and flower, respectively. Hydroxycinnamic acids ranged from 404 µg/g DW in flower buds to 2623 µg/g DW in leaves. Flavonoids showed the highest contents in leaves, while the lowest levels were observed in flowers (2626 µg/g DW). The meaning of the results is discussed in light of the bioactivities of phenolic compounds, concomitant with C. auriculata reported medicinal bioactivities. To our knowledge, this is the first work to identify and quantify polyphenolic compounds in flower and bud of C. auriculata.

scholarly journals Effect of Boron and Calcium on in Vitro and in Vivo Lowbush Blueberry Pollen Germination

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 784B-784
Author(s):  
Youzhi Chen ◽  
John M. Smagula
Keyword(s):  
Pollen Germination ◽  
Pollen Grains ◽  
Germination Percentage ◽  
Control Treatment ◽  
Water Control ◽  
Flower Bud ◽  
Lowbush Blueberry ◽  
To Receive

Ten clones of lowbush blueberry (Vaccinium angustifolium) having low leaf boron (B) concentrations (<20 ppm) were selected to receive fall foliar B (400 ppm), Ca (4000 ppm), B (400 ppm) + Ca (4000 ppm), or water (control). B concentration was raised in stem and bud tissue 3 months after application, but Ca concentration was unaffected. Two randomly selected 5-inch sod plugs from treatment plots within each clone were transported to cold storage at 2.7C for 1000 h to satisfy flower bud dormancy, then to a growth chamber at 24C to blossom. Pollen from plants receiving B had lower in vitro germination rates on 5% agar with 12% lactose after 20 h compared to control and Ca treatments. For in vivo germination, 10 blossoms were randomly selected on sod plugs of each treatment plot to receive 15 control-treatment pollen grains, which were allowed to germinate for 3 days. With the aid of fluorescence microscopy, a higher pollen germination percentage was observed in blossoms of plants receiving B, Ca, and B + Ca. B and Ca may have more influence on the ability of the stigma to stimulate pollen germination than on the germinability of pollen grains themselves.

scholarly journals Pollen of Arbutus unedo: Effects of plant growth regulators

2020 ◽  
Vol 44 (1) ◽  
pp. 55-59
Author(s):  
Zeliha Gökbayrak ◽  
Hakan Engin ◽  
Arda Akçal ◽  
Hatice Kiraz
Keyword(s):  
Growth Medium ◽  
Growth Regulators ◽  
Pollen Germination ◽  
Germination Rate ◽  
Pollen Grains ◽  
Combined Treatments ◽  
Arbutus Unedo ◽  
Antioxidant Characteristics

Arbutus unedo is a species mainly used for landscaping purposes and lately for honey production. Its antioxidant characteristics have also been a subject of of research interest. The germination of pollen grains freshly collected from flowers was tested in vitro, and 30% sucrose gave the highest pollen germination. Subsequently, three growth regulators belonging to the categories of gibberellins and brassinosteroids [24-epibrassinolide (Ebl) and 22S,23S-homobrassinolide (Hbl)] were added to the growth medium singly or in double combinations (gibberellin + brassinosteroid), and the petri dishes were kept for 24 hours at 26?1?C. The results showed that the highest germination rates were obtained from treatments with 0.01 ppm Hbl (45.47%) and 0.001 ppm Hbl (26.74%). They were followed by treatments with 0.001 ppm Ebl, 25 ppm GA3 and 0.1 ppm Ebl. As the concentration of GA3 increased, the germination rate declined considerably. Statistical analysis of the combined treatments showed that combinations of growth regulators lowered the germination rates compared to their individual application. Moreover, action of the lowest GA3 concentration (25 ppm) best matched the effects of brassinosteroids, and increasing the GA3 concentration in combined treatments did not improve germination. The highest germination was obtained with 0.1 ppm Hbl, followed by all Ebl treatments. Brassinosteroids might be an inducer of pollen germination in plants depending on their type and concentrations. When individually included in the growth medium, the extent of this induction was greater with the homobrassinolide than with the epibrassinolide. Their interactions with gibberellins are shown to be mostly dependent on the concentration of gibberellic acid used. The tested epibrassinolide was more consistent than the homobrassinolide in maintaining higher germination levels. The findings of this study indicate that gathering more information from studies involving other plant species is needed to clarify the role of brassinosteroids in in vitro and in vivo germination.

scholarly journals The roles of Fzy/Cdc20 and Fzr/Cdh1 in regulating the destruction of cyclin B in space and time

2002 ◽  
Vol 157 (7) ◽  
pp. 1139-1149 ◽  
Author(s):  
Jordan W. Raff ◽  
Kim Jeffers ◽  
Jun-yong Huang
Keyword(s):  
Cell Cycle ◽  
Triple Point ◽  
Mitotic Spindle ◽  
Cyclin B ◽  
Second Phase ◽  
Point Mutant ◽  
Two Phases ◽  
Drosophila Cells

In Drosophila cells cyclin B is normally degraded in two phases: (a) destruction of the spindle-associated cyclin B initiates at centrosomes and spreads to the spindle equator; and (b) any remaining cytoplasmic cyclin B is degraded slightly later in mitosis. We show that the APC/C regulators Fizzy (Fzy)/Cdc20 and Fzy-related (Fzr)/Cdh1 bind to microtubules in vitro and associate with spindles in vivo. Fzy/Cdc20 is concentrated at kinetochores and centrosomes early in mitosis, whereas Fzr/Cdh1 is concentrated at centrosomes throughout the cell cycle. In syncytial embryos, only Fzy/Cdc20 is present, and only the spindle-associated cyclin B is degraded at the end of mitosis. A destruction box–mutated form of cyclin B (cyclin B triple-point mutant [CBTPM]–GFP) that cannot be targeted for destruction by Fzy/Cdc20, is no longer degraded on spindles in syncytial embryos. However, CBTPM–GFP can be targeted for destruction by Fzr/Cdh1. In cellularized embryos, which normally express Fzr/Cdh1, CBTPM–GFP is degraded throughout the cell but with slowed kinetics. These findings suggest that Fzy/Cdc20 is responsible for catalyzing the first phase of cyclin B destruction that occurs on the mitotic spindle, whereas Fzr/Cdh1 is responsible for catalyzing the second phase of cyclin B destruction that occurs throughout the cell. These observations have important implications for the mechanisms of the spindle checkpoint.

Digestion in the tick,Argas persicus, Oken.

Parasitology ◽  
1964 ◽  
Vol 54 (3) ◽  
pp. 423-440 ◽  
Author(s):  
R. J. Tatchell
Keyword(s):  
Epithelial Cells ◽  
Waste Product ◽  
Aminopeptidase Activity ◽  
Second Phase ◽  
Rapid Phase ◽  
Argas Persicus ◽  
Intracellular Digestion ◽  
Two Phases

1.Studies on the histological changes during digestion in Argas persicus reveal that the ingestion of blood is accompanied by the destruction of the existing gut epithelial cells.2.The blood remains unlysed for 2–3 days while a new epithelium develops which contains cells that secrete a saliva-fast PAS-positive colloid that causes haemolysis.3.Other epithelial cells remove the freed erythrocytic nuclei by phagocytosis.4.Most of the gut cells then absorb protein from the lumen and intracellular digestion takes place leaving pure haematin granules as the waste product of the digestion of haemoglobin.5.After the initial rapid phase of digestion only relatively few cells show signs of absorptive and digestive activity.6.Absorption of protein is accompanied by increased alkaline phosphatase activity in the microvilli of the cell border; this activity is lost once absorption finishes and digestion begins.7.Strong aminopeptidase activity can be demonstrated at the border of some of the protein vacuoles.8.In vitro tests show that the gut proteinase is active only in the acid range with peaks at pH 2·6 and 3·8 and has a Km of 0·32 % with bovine serum albumin as substrate.9.In vivo data show that digestion, after haemolysis has occurred, takes place in two phases; the first is rapid and lasts approximately 1–2 weeks and is followed by the second phase which is slow and remains constant until the next blood feed.10.The proportion of the blood meal which remains after the rapid phase of digestion is determined by the sex and developmental stage of the tick and within each category it is constant and serves, in the absence of significant fat and glycogen reserves, as a food reserve.

scholarly journals Antinociceptive and Antioxidant Activities of Phytol In Vivo and In Vitro Models

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Camila Carolina de Menezes Patrício Santos ◽  
Mirian Stiebbe Salvadori ◽  
Vanine Gomes Mota ◽  
Luciana Muratori Costa ◽  
Antonia Amanda Cardoso de Almeida ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Thiobarbituric Acid ◽  
In Vitro Models ◽  
Control Group ◽  
Second Phase ◽  
Hot Plate Test ◽  
Antinociceptive Effects

The objective of the present study was to evaluate the antinociceptive effects of phytol using chemical and thermal models of nociception in mice and to assess its antioxidant effects in vitro. Phytol was administered intraperitoneally (i.p.) to mice at doses of 25, 50, 100, and 200 mg/kg. In the acetic acid-induced writhing test, phytol significantly reduced the number of contortions compared to the control group (P<0.001). In the formalin test, phytol reduced significantly the amount of time spent in paw licking in both phases (the neurogenic and inflammatory phases), this effect being more pronounced in the second phase (P<0.001). Phytol also provoked a significant increase in latency in the hot plate test. These antinociceptive effects did not impaire the motor performance, as shown in the rotarod test. Phytol demonstrated a strong antioxidant effect in vitro in its capacity to remove hydroxyl radicals and nitric oxide as well as to prevent the formation of thiobarbituric acid reactive substances (TBARS). Taken as a whole, these results show the pronounced antinociceptive effects of phytol in the nociception models used, both through its central and peripheral actions, but also its antioxidant properties demonstrated in the in vitro methods used.

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