The effect of the natural assemblage of microorganisms and selected strains of the yeast Metschnikowia reukaufii in controlling the germination of pollen of the common milkweed Asclepias syriaca

1990 ◽  
Vol 68 (5) ◽  
pp. 1163-1165 ◽  
Author(s):  
D. Eisikowitch ◽  
M. A. Lachance ◽  
P. G. Kevan ◽  
S. Willis ◽  
D. L. Collins-Thompson
Keyword(s):  
Key Words ◽  
Pollen Germination ◽  
Natural Habitat ◽  
Pollen Tubes ◽  
The Other ◽  
Asclepias Syriaca ◽  
Natural Assemblage ◽  
The Common ◽  
Germination Of Pollen

The yeast Metschnikowia reukaufii is a natural contaminant of nectar and is vectored to the flowers of the field milkweed Asclepias syriaca by insects, some of which are pollinators of the plants. In its natural habitat, the yeast inhibits the germination of the milkweed's pollen, which normally uses nectar in the stigmatic cavity for germination. This inhibition is irreversible after about 8 h of exposure to the yeasts. Two selected strains of the yeast were isolated and investigated for their effects on pollen germination in vitro. The two strains, and their mixture, affected pollen germination adversely by reducing its amount and vigour and causing any pollen tubes that were produced to burst: One strain was more virulent than the other, and the mixture seemed to have an additive effect. The strains may be more efficacious than the natural assemblage of microbes in disrupting fertilization of milkweed flowers because they cause the immediate death (bursting) of the growing microgametophyte (pollen and tube). Key words: yeasts, pollen germination, milkweed, Metschnikowia reukaufii, Asclepias syriaca.

GERMINATION OF SWEET CHERRY (PRUNUS AVIUM L.) POLLEN IN VITRO AS INFLUENCED BY FUNGICIDES

1961 ◽  
Vol 41 (4) ◽  
pp. 740-743 ◽  
Author(s):  
G. W. Eaton
Keyword(s):  
Pollen Germination ◽  
Sweet Cherry ◽  
Prunus Avium ◽  
Pollen Tubes ◽  
Germination Of Pollen ◽  
Germination And Growth ◽  
Prunus Avium L

Effects of fungicidal concentrations of sulphur, dichlone, ferbam, and captan on sweet cherry (Prunus avium L.) pollen germination and growth were studied in artificial media. Sulphur did not reduce the germination of pollen. Dichlone and ferbam reduced germination from 53.0 per cent to 47.1 per cent and 40 per cent, respectively, reductions which were significant statistically. Sprayed at 0.2 pound/100 gallons or less, captan did not reduce germination. Captan, sprayed at 2 pounds/100 gallons, almost entirely prevented pollen germination, and arrested the elongation of pollen tubes.

Germination of pollen of the dwarf mistletoe Arceuthobium americanum

1991 ◽  
Vol 69 (3) ◽  
pp. 685-688 ◽  
Author(s):  
Jeannie Gilbert ◽  
David Punter
Keyword(s):  
Key Words ◽  
Pollen Germination ◽  
Pinus Banksiana ◽  
Optimum Temperature ◽  
Dwarf Mistletoe ◽  
In Vitro Pollen Germination ◽  
Arceuthobium Americanum ◽  
Pollen Germinability ◽  
Germination Of Pollen

Pollen of Arceuthobium americanum Nuttall ex Engelmann, a parasitic dwarf mistletoe of Pinus banksiana Lamb, in Manitoba, was germinated on media containing a range of concentrations of sucrose and salts. Highest germination levels occurred on 20% sucrose agar; addition of salts significantly depressed germination. Pollen germinability was below 5% at first but increased to near 50% as the season advanced. Mean germination differed significantly between flowers from 10 staminate plants but peaked at approximately the same times in association with increasing temperatures. Freezing night temperatures were followed by reduced germinability. The optimum temperature for in vitro pollen germination is close to 30 °C, whereas 40 °C impairs germination. Key words: parasitic angiosperms, microclimate, jack pine, reproductive biology.

HISTOPATHOLOGY OF THE PIGMENTED TUMORAL-LIKE LESIONS OF THE SKIN AT HUE HOSPITAL OF MEDICINE AND PHARMACY UNIVERSITY

2018 ◽  
Vol 8 (4) ◽  
pp. 65-69
Author(s):  
Mao Nguyen Van ◽  
Dong Tran Nam
Keyword(s):  
Key Words ◽  
Definitive Diagnosis ◽  
The Other ◽  
Cell Tumour ◽  
Cross Sectional ◽  
Skin Tumour ◽  
Clinical Appearance ◽  
The Face ◽  
The Common ◽  
Difficult Cases

Background: Pigmented tumour of the skin is one of the common tumour in human including the benign pigmented tumours (more common) called Nevi tumours and the malignant one called melanoma which was less frequent but the most poor in prognosis. In addition, the others not belonging to these group had the same clinical appearance, so the application of histopathology and immunohistochemistry for the definitive diagnosis was indespensible. Objectives: 1. To describe the macroscopic features of the pigmented tumoral-like lesions; 2. To classify the histopathologic types of the pigmented cell tumours and the other pigmented tumours of the skin. Materials and Method: Cross-sectional research on 55 patients diagnosed as pigmented tumoral lesions by clinician, then all definitively diagnosed by histopathology combining the immunohistochemistry in difficult cases. Results: There was no difference in gender, the disease was discovered most common in adult, especially with the age over 51 years old (58.1%). the most region located was in the face accounting for 60%, following the trunk and limbs (14.6%, 12.8% respectively). All 3 malignant melanomas happened in foot. The most common color of the lesions was black (65.4%), the other ones were rose, grey and blue. Histopathology and immunohisthochemistry showed that the true pigmented cell tumours were 52.6% encompassing benign ones (Nevi tumour) (41.8%), melanoma (5.4%) and lentigo (5.4%). 47.4% was not the true pigmented cell tumour including pigmented basocellular carcinoma (36.4%) and the others less common as histiofibromas, acanthoma and papilloma. Conclusion: the pigmented tumoral-like lesions of the skin could be the true pigmented cell tumours and the others, so the application of the histopathology and the immunohistochemistry after the clinical discovery helps to determine and classify the disease definitely and for the best orientation of treatment as well. Key words: skin tumour, benign pigmented tumour (Nevi), malignant pigmented tumour (melanoma), pigmented basocellular carcinoma

scholarly journals Hyperoside promotes pollen tube growth by regulating the depolymerization effect of actin-depolymerizing factor 1 on microfilaments in okra

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Biying Dong ◽  
Qing Yang ◽  
Zhihua Song ◽  
Lili Niu ◽  
Hongyan Cao ◽  
...  
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Pollen Germination ◽  
Pollen Tubes ◽  
Tube Growth ◽  
Actin Depolymerizing Factor ◽  
Specific Mechanism ◽  
Promoting Effect ◽  
New Research

AbstractMature pollen germinates rapidly on the stigma, extending its pollen tube to deliver sperm cells to the ovule for fertilization. The success of this process is an important factor that limits output. The flavonoid content increased significantly during pollen germination and pollen tube growth, which suggests it may play an important role in these processes. However, the specific mechanism of this involvement has been little researched. Our previous research found that hyperoside can prolong the flowering period of Abelmoschus esculentus (okra), but its specific mechanism is still unclear. Therefore, in this study, we focused on the effect of hyperoside in regulating the actin-depolymerizing factor (ADF), which further affects the germination and growth of pollen. We found that hyperoside can prolong the effective pollination period of okra by 2–3-fold and promote the growth of pollen tubes in the style. Then, we used Nicotiana benthamiana cells as a research system and found that hyperoside accelerates the depolymerization of intercellular microfilaments. Hyperoside can promote pollen germination and pollen tube elongation in vitro. Moreover, AeADF1 was identified out of all AeADF genes as being highly expressed in pollen tubes in response to hyperoside. In addition, hyperoside promoted AeADF1-mediated microfilament dissipation according to microfilament severing experiments in vitro. In the pollen tube, the gene expression of AeADF1 was reduced to 1/5 by oligonucleotide transfection. The decrease in the expression level of AeADF1 partially reduced the promoting effect of hyperoside on pollen germination and pollen tube growth. This research provides new research directions for flavonoids in reproductive development.

scholarly journals Consistency of in vitro drug sensitivities within pharmacological classes

2021 ◽  
Vol 15 (1) ◽  
pp. 12
Author(s):  
Casey Hon ◽  
Sisira Nair ◽  
Petr Smirnov ◽  
Hossein Sharifi-Noghabi ◽  
Nikta Feizi ◽  
...  
Keyword(s):  
Cell Lines ◽  
Drug Sensitivity ◽  
Cancer Therapeutics ◽  
The Other ◽  
Comparative Analyses ◽  
Potential Sources ◽  
The Common ◽  
Pharmacogenomic Studies

Multiple comparative analyses between the common drugs and cell lines of the Genomics of Drug Sensitivity in Cancer (GDSC) and the Cancer Therapeutics Response Portal (CTRP) have previously shown low consistency between the in vitro phenotypic measures of a drug in one study with the other. While several potential sources of inconsistency have been tested, the similar targets of tested compounds has yet to be tested as a contributing factor of discrepancy. This analysis includes two methods of reclassifying drugs into classes based on their targets to identify the truer set of consistent cell lines, showing an increased correlation between the two pharmacogenomic studies.

scholarly journals Foliar Application of Boron to Almond Trees Affects Pollen Quality

2000 ◽  
Vol 125 (2) ◽  
pp. 265-270 ◽  
Author(s):  
A.M.S. Nyomora ◽  
P.H. Brown ◽  
K. Pinney ◽  
V.S. Polito
Keyword(s):  
Pollen Germination ◽  
Foliar Application ◽  
Culture Media ◽  
Pollen Viability ◽  
Prunus Dulcis ◽  
Pollen Tubes ◽  
Tube Growth ◽  
Mature Trees

The effect of boron (B) on in vivo and in vitro development of almond [Prunus dulcis (Mill.) D.A. Webb (syn. P. amygdalus Batsch)] pollen and pollen tubes and the resultant effect on fruit set was studied in mature trees. The cultivars Mono (pistil donor) and Butte (pollinizer) in an orchard with low soil B in Fresno, California were sprayed with B at 0, 0.8, 1.7, or 2.5 kg·ha-1 during Fall 1993. Pollen viability as indicated by the fluorescein diacetate method (FDA) was >85% and was not affected by field-applied B, however, in vivo pollen germination and tube growth were enhanced by foliar-applied B. More effect of applied B on in vivo growth appeared as pollen tubes progressed toward the ovary. For in vitro germination, foliar-applied B reduced bursting of tubes, and addition of B to the culture media significantly increased pollen germination and pollen tube growth.

scholarly journals Efecto de los factores determinantes para el establecimiento de microesquejes de papaya (Carica papaya L.)

Respuestas ◽  
2015 ◽  
Vol 15 (1) ◽  
pp. 5-12
Author(s):  
Jesús Arturo Ramírez Sulvarán
Keyword(s):  
Production Process ◽  
Key Words ◽  
Statistical Method ◽  
Carica Papaya ◽  
The Other ◽  
Tropical Fruits ◽  
Important Goal ◽  
Experimental Procedure ◽  
Micro Propagation

El objetivo fue determinar los efectos de los factores para el establecimiento de microesquejes de papaya. Se incluyeron los efectos de los factores: 1. Protocolo de desinfección. 2. Variedad. 3. Edad de la planta donadora. 4. Número de yemas por microesquejes. 5. Los componentes hormonales en los medios de cultivo y 6. La temperatura de desarrollo de los microesquejes. Los resultados se analizaron estadísticamente mediante tablas de contingencia. También se encontró la correlación entre las variables. Los resultados indican que las mejores condiciones para el establecimiento de los microesquejes fueron: 1.Desinfección con hipoclorito al 1,5% durante 5 minutos. 2. La variedad de papaya Roja Melonera. 3. La edad optima de las plantas donadora fue a los 60 días. 4. Los mejor microesquejes eran los que poseía 2 yemas. 5. La relación hormonal optima fue ANA 0,1 mg/l y BAP 0,5 mg/l. 6. La temperatura de desarrollo óptima fue a 27° C. Se concluyó que todos los factores estudiados presentaron efecto sobre el desarrollo y crecimiento de los microesquejes de papaya. De esta forma es necesario abordar estos procesos con un enfoque multifactorial.Palabras clave: Carica papaya, microesqueje, establecimiento, multifactorial. AbstractPrevious studies on apical and axilar microesqueje micropropagation of papaya have been lined up and without a systemic working. Consequently, it arises the actual research, which brough into study all the variables and parameters and their relationships, in order to improve the vitroplants production process, more efficiently. The main purpose of this study was to establish the effects of the former and in vitro factors, which have incidence upon the establishment of microesquejes. The effects of the former variables previous to the in vitro growing, which were studied, were: Sanitizing procedure, variety incidence, mother plant age incidence, among other ones. On the other hand, the in vitro variables studied were: temperature and hormonal compositions of the crops. Respuestas Año 15 No. 1 Junio 2010 ISSN 0122-820X This research was held at the vegetal biotechnology laboratory, which belongs to the biotechnology complex of the Universidad Francisco de Paula Santander in “Los Patios” Norte de Santander, Colombia. The experimental procedure was held with two months old plants from “Maradol” and “Roja Melonera” varieties. In order to accomplish the different effects of each one of the variables, it was used qualitative statistical method for their measurements. The final results showed that all factors were important to the papaya microesquejes micro propagation. As a result, the actual conclusion was to introduce the necessity to give a systemic focusing to the process in order to improve the efficiency in the vitroplants production, where all the factors and their relationships must be considered. Finally, the most important goal of this study is that all these results could be extended beyond other researches related to tropical fruits micro propagation, so important to the tropical micro propagation workers. Key Words: Carica papaya, microcuttings, establishment, multifactors.

scholarly journals Putrescine Increases Effective Pollination Period in Roses

1992 ◽  
Vol 2 (2) ◽  
pp. 211-213 ◽  
Author(s):  
Serge Gudin ◽  
Laurence Aréne
Keyword(s):  
Pollen Germination ◽  
Pollen Grains ◽  
Pollen Tubes ◽  
Rosa Hybrida ◽  
In Vitro Pollen Germination ◽  
Stigmatic Exudate ◽  
Germinated Pollen ◽  
Number Of Seeds

Flowers of two cultivars of Rosa hybrida were treated or not with putrescine before being pollinated from 2 to 8 days after anther emasculation. On both cultivars the 10-3 M putrescine treatment extended the effective pollination period, as shown by the best hip formation rates and mean number of seeds per hip. On one cultivar, the 10-5 M putrescine treatment increased fertilization efficiency (more hips obtained). The effect of putrescine was proportionally more important on the cultivar characterized by the highest stigmatic exudate pH. Putrescine also influenced in vitro pollen germination by increasing the length of emitted pollen tubes (10-3 and 10-5 M-putrescine) and the quantity of germinated pollen grains (10-5 M putrescine).

scholarly journals Multiple paternity in Asclepias syriaca using a paired-fruit analysis

1995 ◽  
Vol 73 (8) ◽  
pp. 1212-1216 ◽  
Author(s):  
Julie J. Gold ◽  
Joel S. Shore
Keyword(s):  
Maximum Likelihood ◽  
Key Words ◽  
Multiple Paternity ◽  
Statistical Evidence ◽  
Likelihood Methods ◽  
Asclepias Syriaca ◽  
Maximum Likelihood Methods ◽  
Fruit Abortion ◽  
The Common ◽  
Common Milkweed Asclepias Syriaca

We investigated the extent of multiple paternity within and between fruits of the common milkweed, Asclepias syriaca, at one site. Using isozyme polymorphisms at four loci and the maximum likelihood methods of Williams and Evarts (1989), we found no statistical evidence for multiple paternity within fruits. When pairs of fruits obtained from individual ramets were analyzed in a similar manner, extensive multiple paternity was observed, indicating that fruits on the same ramet are sired by different paternal parents. This extensive multiple paternity between fruits provides considerable opportunity for maternal choice via selective fruit abortion. Key words: Asclepias, isozyme polymorphisms, multiple paternity, pollinia.

Interspecific Incompatibility Amongst Victorian Species of Amyema (Loranthaceae)

1982 ◽  
Vol 30 (2) ◽  
pp. 175 ◽  
Author(s):  
P Bernhardt
Keyword(s):  
Pollen Viability ◽  
Interspecific Cross ◽  
Pollen Tubes ◽  
The Other ◽  
Current Evidence ◽  
Interspecific Crosses ◽  
Natural Distribution ◽  
Interspecific Incompatibility ◽  
Pollen Tube Penetration

Each of the six Amyema species collected in Victoria had a natural distribution and floral phenoiogy that overlapped with at least one of its Victorian congenerics. All of the Amyema spp. were pollinated by the same family of birds (Meliphagidae, honeyeaters) and often by the same species. All intraspecific cross-pollinations in vitro consistently produced an average of more than five pollen tubes per style which grew more than 0.125 the length of the style within 24 hours. Seventeen of 30 interspecific pollinations in vitro failed to produce pollen tubes in the style over the same time. Only eight of the 30 interspecific crosses attempted produced results competitive with respective intraspecific crosses. The success of the interspecific cross appeared to depend on the breeding system of the species receiving pollen from another. Self-incompatible Amyema pendulum (Sieb. ex Spreng.) Van Tieghem and Amyema miraculosum (Miq.) Van Tieghem repeatedly failed to accept the pollen of all the other species. Seif- compatible Amyema preisii (Miq.) Van Tieghem and Amyema quandang (Lindl.) Van Tieghem showed good to excellent interspecific pollen tube penetration of stylar tissue. Partially self-compatible Amyema linophyllum (Fenzl) Van Tieghem and Amyema miquelii (Lehm. ex Miq.) Van Tieghem showed results intermediate between self-compatible and self-incompatible taxa. Geographic and floral phenological barriers contribute partially to interspecific isolation as intercompatible species may have regionally different flowering seasons and distributions. F, hybrids recorded in southern Australia show extremely low rates of pollen viability and seed production. There is no current evidence that introgression occurs.

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