scholarly journals Flowering Biology of Rhododendron pulchrum

Horticulturae ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 508
Author(s):  
Jie Qiu ◽  
Chao Gao ◽  
Hongli Wei ◽  
Biao Wang ◽  
Yang Hu ◽  
...  
Keyword(s):  
Colorimetric Assay ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Experimental Period ◽  
Polar Axis ◽  
Flowering Phenology ◽  
Mtt Colorimetric Assay ◽  
Single Flower ◽  
Axis Length ◽  
To Receive

To study the flowering biology of Rhododendron pulchrum, we used scanning electron microscopy (SEM) and paraffin sectioning to observe the microstructures of its floral organs, a methyl thiazolyl tetrazolium (MTT) colorimetric assay to detect pollen viability in different periods, continuous observations to study flowering phenology, and artificial pollination and a benzidine-hydrogen peroxide method to determine stigma receptivity. R. pulchrum exhibited a centralized flowering phenology. The protogynous stigmas of R. pulchrum were able to receive pollen before flowering. The pollen grains of R. pulchrum fused into tetrads, the average ratio of the polar axis length to the equatorial axis length (P/E) was 1.05, and the pollen viability was highest in the initial flowering period, reaching 88.98%. The pollen/ovule (P/O) ratio was 266–328, and the outcrossing index (OCI) was 4; the vitality of R. pulchrum pollen remained high in the initial flowering and blooming periods. Compared with the lifespan of a single flower, pollen vitality remained high for most of the experimental period, thereby improving male fitness. The P/O ratio suggests that R. pulchrum may have a facultative outcrossing breeding system. The OCI estimation suggests that R. pulchrum is partially self-compatible, most likely requiring pollinators to complete pollination.

scholarly journals Nutritive for insects attractantsin Asphodelus albus Miller flowers

2012 ◽  
Vol 59 (1) ◽  
pp. 155-164 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Mirosława Chwil
Keyword(s):  
Pollen Viability ◽  
Pollen Grains ◽  
Polar View ◽  
Polar Axis ◽  
Longitudinal Axis ◽  
Botanical Garden ◽  
Climatic Conditions ◽  
Nectar Secretion ◽  
Transverse Axis ◽  
Single Flower

The studies on <i>Asphodelus albus</i> Miller flowers were conducted in the Botanical Garden of the UMCS in Lublin in the years 2004-2005. The flower nectaries location was determined in a stereoscopic microscope. The nectaring abundance was studied with a pipette method described by Jabłoński and Szklanowska (1979), while pollen efficiency determined after Warakomska`s ether method (1972). Pollen viability was computed in a sample of 400 grains after acetocarmine staining. The following measurements of pollen grains were made: the length of polar axis (P), equatorial longitudinal axis (EL) and equatorial transverse axis (ET). In <i>Asphodelus albus</i> flowers, there are three nectary glands located in the ovary septa whose outlets are situated in the upper part of the ovary. The nectar secretion starts in a dehiscing bud and persists until the withering stage of perianth leaves. Considering the size of monocolpate pollen grains of <i>Asphodelus albus</i>, they are ranked among great, whereas their shape assumed flattened and circular at the polar view. In the Poland climatic conditions, a pollen showed high vitality (98%). The <i>Asphodelus albus</i> plants constitute a valuable source of nutrition for the pollinators as a single flower generated on average 4,22 mg sugars and 0,2 mg of pollen grains.

scholarly journals Morphology and pollen viability of Lolium multiflorum Lam.

2012 ◽  
Vol 36 (2) ◽  
pp. 180-188 ◽  
Author(s):  
Renata de Castro Nunes ◽  
Fernanda de Oliveira Bustamante ◽  
Vânia Helena Techio ◽  
Andréa Mittelmann
Keyword(s):  
Lolium Multiflorum ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Polar Axis ◽  
High Rate ◽  
Breeding Programs ◽  
Ploidy Levels ◽  
Equatorial Diameter ◽  
Breeding Populations

Study and characterization of pollen grains are essential for different areas, especially taxonomy, genetic improvement, phylogeny, and paleobotany. As yet, there are no reports on pollen morphology of genotypes of naturalized Lolium multiflorum Lam., introduced cultivars or breeding populations, diploid or polyploid. Ten genotypes of annual ryegrass (L. multiflorum) were evaluated for the viability of pollen grains using propionic carmine and Alexander's stains, while morphology was assessed by the acetolysis technique. Measures of polar axis (P), equatorial diameter (E), exine thickness, and analysis of pollen grains were obtained by scanning electron microscopy (SEM). All genotypes showed high rate of pollen viability (> 89%) for both stains. There were differences between genotypes in the following quantitative traits: polar axis, equatorial diameter, exine, endexine, ektexine, and P/E ratio. Pollen grains were characterized as small, monoporates, with circular and non-prominent apertures. In addition to helping distinction of pollen grains, morphometric differences can be used later to compare ploidy levels, thus assisting in breeding programs of the species.

scholarly journals Pollen Morphology of Herbaceous Peonies with Different Ploidy Levels

2016 ◽  
Vol 141 (3) ◽  
pp. 275-284 ◽  
Author(s):  
Lihong Hao ◽  
Hui Ma ◽  
Jaime A. Teixeira da Silva ◽  
XiaoNan Yu
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Polar View ◽  
Polar Axis ◽  
Hybrid Breeding ◽  
Ploidy Levels ◽  
Herbaceous Peony ◽  
Group I ◽  
Surface Ornamentation ◽  
Axis Length

The pollen morphology of 26 cultivars of herbaceous peony (Paeonia L.) was examined by scanning electron microscopy (SEM). Pollen grains of the cultivars were mostly subprolate to perprolate, tricolporate, or ellipsoidal in equatorial view, but rounded-trifid in polar view. The poles of pollen grains were mainly flat when viewed in cross-section and only a few appeared to have a circular or arc shape. In addition, the surface of the pollen grains was psilate, and the muri were partly or fully protuberant with a reticulate surface sculpture. However, the shapes and sizes of pollen grains as well as surface ornamentation varied significantly among cultivars with different chromosome numbers. The pollen grains from diploid cultivars were regular and full, and the reticulation holes were evenly distributed, while most of the pollen grains from triploid cultivars were empty flat shells with some heteromorphic pollen whose surface ornamentation was mostly rugulate-reticulate exine. The pollen grains from tetraploid cultivars were the largest although pollen morphology and surface ornamentation differed between Athena and Cream Delight. Six indices [polar axis length (P), equator axis length (E), P/E, pollen perforation diameter (D), ridge width (W), and D/W] were used in Q cluster analysis, which divided the 26 cultivars into three groups. Group I included eight diploid, four triploid, and one tetraploid cultivar. Group II included 12 triploid cultivars with complex genetic backgrounds. Group III included only one tetraploid cultivar Cream Delight. This work may provide an important palynological basis for studying taxonomy and hybrid breeding of herbaceous peony cultivars.

Pollen morphology of some Verbascum (Scrophulariaceae) taxa in Turkey

Phytotaxa ◽  
2018 ◽  
Vol 333 (2) ◽  
pp. 209 ◽  
Author(s):  
AYŞE ÖZTÜRK ◽  
KUDRET BETÜL GÜNEY ◽  
BARIŞ BANİ ◽  
KERİM GÜNEY ◽  
FAİK AHMET KARAVELİOĞULLARI ◽  
...  
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Polar Axis ◽  
Prolate Spheroidal ◽  
Oblate Spheroidal ◽  
General Terms ◽  
Surface Ornamentation ◽  
Pollen Shape ◽  
Axis Length ◽  
Scanning Electron

Pollen morphology of six Verbascum (Scrophulariaceae) taxa belonging to five different groups in the genus [V. georgicum (group E), V. nudatum var. nudatum (group F), V. cariense (group F), V. bithynicum (group H), V. pycnostachyum (group K), and V. lasianthum (group L)] was studied. Pollen slides were prepared according to the Woodhouse method and were examined with light-microscopy (LM) and Scanning Electron Microscopy (SEM). All studied pollen grains are generally monads, though tetrads (5 %) were observed in Verbascum nudatum var. nudatum. Pollen grains of all studied taxa were determined as isopolar and radially symmetric. In general terms, aperture types are trizonocolporate, but also trisyncolpate (V. lasianthum 10 %, V. pycnostachum 1 %, and V. georgicum 4 %) and trizonocolpate (V. cariense 10 %, V. bithynicum 10%, V. lasianthum 90%, V. pycnostachyum 9%, and V. georgicum 96 %) aperture types were observed. The shapes of the pollen grains were determined as prolate, subprolate, prolate-spheroidal and oblate-spheroidal. The sculpture was reticulate in all cases. The results of the study corroborate that morphological features, such as pollen shape, polar axis length (P), equatorial axis length (L), aperture type, surface ornamentation, muri thickness, and lumina shape, show differences which can be taken into consideration in the systematic discrimination within the groups, and also for discrimination of the groups in the genus.

scholarly journals Pollen Morphology of Some Turkish Salvia L. (Lamiaceae: Mentheae) Species

2020 ◽  
Vol 38 ◽  
Author(s):  
K. AKTA ◽  
C. ÖZDEMIR ◽  
M. ÖZKAN ◽  
P. BARAN
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Polar Axis ◽  
Radial Symmetry ◽  
Exine Ornamentation ◽  
Pollen Shape ◽  
Axis Length ◽  
Different Characteristics ◽  
Scanning Electron

ABSTRACT: In this presented work, the pollen morphologies of twenty-one taxa, nine of them endemic from Turkey, belonging to the genus Salvia (Lamiaceae: sub-family Nepetoideae: tribe Mentheae: sub-tribe Salviinae), S. aethiopis L., S. argentea L., S. aytachii Vural & Adigüzel, S. blepharochlaena Hedge & Hub.-Mor., S. cadmica Boiss., S. ceratophylla L., S. cryptantha Montbret & Aucher, S. frigida Boiss., S. fructicosa Miller, S. halophile Hedge, S. napifolia Jacq., S. microstegia Boiss. & Bal., S. recognita Fisch. & Mey. S. sclarea L., S. smyrnaea Boiss. S. suffruticosa Montbret & Aucher, S. tchihatcheffii (Fisch. & Mey.) Boiss., S. tometosa Bertol, S. verbenaca L., S. viridis L., and S. wiedemanni Boiss. and collected throughout the Turkey, have been intensively studied by using light (LM) and a scanning electron (SEM) microscopy. The objectives of this study are to investigate the pollen morphologies of twenty-one taxa of Turkish Salvia (nine of which are endemic) and to present similar and different characteristics of the taxa. The investigated whole pollen grains had a structure of both isopolar and radial symmetry. Overall, types of aperture were mostly hexacolpate, but it was also determined that the aperture type of S. viridis was both hexacolpate and octacolpate. The pollen grains had characteristic shapes of spheroidal, suboblate, prolate and subprolate. The exine ornamentation was bireticulate and reticulate-perforate. It was determined by the results of palynological studies that pollen morphology changed amongst these studied taxa. As a conclusion, the results of the present study show that palynological characters such as pollen shape, polar axis length (P), equatorial axis length (E), aperture numbers and types and exine ornamentation, exhibit remarkable differences amongst the studied taxa.

scholarly journals Pollen morphology and variability of species from the genus Rubus L. (Rosaceae) alien and invasive in Poland

Webbia ◽  
2021 ◽  
Vol 76 (1) ◽  
pp. 109-121
Author(s):  
Kacper Lechowicz ◽  
Jan Bocianowski ◽  
Dorota Wrońska-Pilarek
Keyword(s):  
Alien Species ◽  
Pollen Morphology ◽  
Pollen Viability ◽  
Intraspecific Variability ◽  
Pollen Grains ◽  
Polar Axis ◽  
Exine Ornamentation ◽  
The Family ◽  
Rubus Species

Rubus L. is one of the most species-rich and most taxonomically challenging genera in the family Rosaceae. The aim of this study was to investigate pollen morphology and the ranges of inter- and intraspecific variability of the studied Rubus alien species, as well as verify the taxonomic usefulness of these traits in distinguishing studied taxa from this genus. We analysed six quantitative pollen characteristics and the following qualitative ones: exine ornamentation, pollen outline and shape. The study was conducted on 24 samples of six alien Rubus species found in Poland. 720 pollen grains were measured in total. The most important pollen features included exine ornamentation and length of the polar axis (P). In the conducted studies there were no features of pollen indicating “invasiveness”. The results of our research fill the gap in knowledge on pollen structure in Rubus species alien to Poland and Europe. They may constitute a foundation for further research on the reproduction of these species (e.g. pollen viability and fertility), thus facilitating identification of features determining their expansive character.

scholarly journals A Duplicated Copy of the Meiotic Gene ZIP4 Preserves up to 50% Pollen Viability and Grain Number in Polyploid Wheat

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 290
Author(s):  
Abdul Kader Alabdullah ◽  
Graham Moore ◽  
Azahara C. Martín
Keyword(s):  
Pollen Viability ◽  
Pollen Grains ◽  
Wheat Chromosome ◽  
Grain Number ◽  
Meiotic Gene ◽  
Chromosome 5B ◽  
Mutant Pollen ◽  
Female Gametogenesis ◽  
Chromosome 3B

Although most flowering plants are polyploid, little is known of how the meiotic process evolves after polyploidisation to stabilise and preserve fertility. On wheat polyploidisation, the major meiotic gene ZIP4 on chromosome 3B duplicated onto 5B and diverged (TaZIP4-B2). TaZIP4-B2 was recently shown to promote homologous pairing, synapsis and crossover, and suppress homoeologous crossover. We therefore suspected that these meiotic stabilising effects could be important for preserving wheat fertility. A CRISPR Tazip4-B2 mutant was exploited to assess the contribution of the 5B duplicated ZIP4 copy in maintaining pollen viability and grain setting. Analysis demonstrated abnormalities in 56% of meiocytes in the Tazip4-B2 mutant, with micronuclei in 50% of tetrads, reduced size in 48% of pollen grains and a near 50% reduction in grain number. Further studies showed that most of the reduced grain number occurred when Tazip4-B2 mutant plants were pollinated with the less viable Tazip4-B2 mutant pollen rather than with wild type pollen, suggesting that the stabilising effect of TaZIP4-B2 on meiosis has a greater consequence in subsequent male, rather than female gametogenesis. These studies reveal the extraordinary value of the wheat chromosome 5B TaZIP4-B2 duplication to agriculture and human nutrition. Future studies should further investigate the role of TaZIP4-B2 on female fertility and assess whether different TaZIP4-B2 alleles exhibit variable effects on meiotic stabilisation and/or resistance to temperature change.

Scanning electron microscopy observations of pollen morphology in common vetch (Vicia sativa) subspecies

2021 ◽  
pp. 1-14
Author(s):  
Rui Dong ◽  
Zhongjie Lu ◽  
Zhengyu Yang ◽  
Yanrong Wang ◽  
Chao Chen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pollen Morphology ◽  
Polar View ◽  
Polar Axis ◽  
Vicia Sativa ◽  
Common Vetch ◽  
Plant Phylogeny ◽  
Axis Length ◽  
Scanning Electron

Abstract Common vetch (Vicia sativa) is an important forage and green manure crop that is widely cultivated around the world. However, the large number of subspecies and accessions of common vetch has made taxonomic research on this species difficult. Pollen morphology data can provide important evidence in the study of plant phylogeny. Therefore, in this research, light microscopy and scanning electron microscopy were used to observe seven morphological traits of pollens from 22 common vetch accessions, and residual maximum likelihood and pattern analysis was conducted. The results showed that the pollen grains of the 22 accessions were all monad pollen and the polar view revealed three-lobed circular and triangular shapes, while the equatorial view mainly revealed an oblate shape; only one accession showed an oblate spherical shape. All accessions were 3-zonocolporate and the colpus length extended close to the poles. The polar axis length was (19.39 ± 0.97)–(42.12 ± 0.76) μm and the equatorial axis length was (35.97 ± 1.27)–(45.25 ± 0.81) μm. We found that qualitative traits of pollen shape, aperture polar view and ornamentation were highly stable. Among them, polar axis length, equatorial axis length and colpus length and width had significant differences among the accessions. The ratios of the equatorial and polar axes had significant differences among the subspecies. This trait information could be used for the classification and identification of common vetch accessions and subspecies.

Exploration of the in vitro cytotoxic and antiviral activities of different medicinal plants against infectious bursal disease (IBD) virus

2014 ◽  
Vol 9 (5) ◽  
pp. 531-542 ◽  
Author(s):  
Waqas Ahmad ◽  
Sohail Ejaz ◽  
Khaleeq Anwar ◽  
Muhammad Ashraf
Keyword(s):  
Medicinal Plants ◽  
Colorimetric Assay ◽  
Rna Virus ◽  
Infectious Bursal Disease ◽  
Dna Viruses ◽  
Mtt Colorimetric Assay ◽  
Bursal Disease ◽  
Dried Fruit ◽  
Antiviral Activities

AbstractInfectious bursal disease (IBD) caused by non-enveloped double stranded RNA virus is an acute and contagious poultry disease. Outbreak of IBD could result in 10–75% mortality of the birds; hence it has gained socio-economic importance worldwide. Medicinal plants have shown broad spectrum anti-viral activities against RNA and DNA viruses. Moringa oleifera Lam (MOL), Phyllanthus emblicus Linn (PEL), Glycyrrhiza glabra Linn (GGL), and Eugenia jambolana Lam (EJL) are commonly available medicinal plants of the sub-continent and exhibited anti-viral potential against different viruses. Ethanolic extracts of the leaves of MOL and EJL, roots of GGL and dried fruit of PEL were investigated for their cytotoxic and anti-viral potential against IBD virus using MTT colorimetric assay and anti-viral assay. Significant anti-viral potential (P<0.001) was demonstrated at concentrations 12.5, 25, 50 and 100 µg ml−1 of GGL, PEL, MOL and EJL, respectively, with no cytotoxicity. Data also spotlighted that all tested plant extracts possess significant anti-viral potential and this trend was higher in GGL followed by PEL, MOL, and EJL. The data undoubtedly conclude that these medicinal plants contain several health beneficial phyto-chemicals which got significant anti-viral potential and effectively be utilized against IBD virus. Moreover, the outcomes of this study provide a platform on the way to discover novel anti-viral agents against IBD virus and other viruses from plant origin.

PSXIII-15 Impact of forage allowance on performance and reproductive parameters in Nellore heifers

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 467-468
Author(s):  
Igor M Ferreira ◽  
Iorrano A Cidrini ◽  
Karla Oliveira ◽  
Luciana Sousa ◽  
Laura F Prados ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Treatment Effect ◽  
Average Daily Gain ◽  
Experimental Period ◽  
Fixed Time ◽  
Carcass Composition ◽  
Stocking Rate ◽  
Treatment Conditions ◽  
To Receive ◽  
Daily Gain

Abstract The objective was to evaluate the effects of forage allowance on the performance and pregnancy rate of Nellore heifers submitted to the fixed-time artificial insemination (FTAI) at 14±1 months. The experimental period was divided into the growing phase (GP; 173d) and breeding season (83d). Ninety weaned Nellore heifers [169±19 kg of body weight (BW); 210±28 days of age] were blocked by initial BW and randomly assigned to receive different forage allowance: (1) High (HFA; 7.17 kgDM/kgBW; and (2) Low (LFA; 3.27 kgDM/kgBW); and divided into 6 paddocks (2.15 to 2.4 ha each one). The grazing method used was continuous stocking with a variable stocking rate where treatment conditions were established varying the stocking rate on pasture (put-and-take). The supplement consisted of corn, soybean meal, urea, monensin, sodium chloride and minerals mix (80% TDN and 24% CP) and was provided daily (ad libitum; expected intake around 1% of BW). The final pregnancy rate was determined after two FTAI (d256). Heifers BW at the end of the GP was greater (P &lt; 0.01) for HFA vs. LFA (268 vs. 255 kg). The overall average daily gain (ADG) was greater 68 g/d for animals maintained in HFA than LFA (P &lt; 0.01; 0.713 vs. 0.645 kg/d). Supplement intake (kg/animal/d) had no treatment effect (P = 0.117). On d173, forage allowance affected (P &lt; 0.01) the backfat thickness obtained by real-time carcass ultrasound (HFA = 3.08 vs. LFA = 2.85 mm). The pregnancy rate had no treatment effect (P = 0.223; on average 61%). However, the pregnant heifers per hectare had treatment effect (P = 0.036; HFA = 3.78 vs. LFA = 2.72 pregnant heifers/ha). In conclusion, the low forage allowance reduces the animal performance and affects the carcass composition but provides a greater number of pregnant heifers per hectare.

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