scholarly journals Effect of Relative Humidity on the Development of Head Blight by Bipolaris sorokiniana in Wheat

1970 ◽  
Vol 4 (1) ◽  
pp. 61-65 ◽  
Author(s):  
Sheikh Afsar Uddin ◽  
KM Khalequzzaman ◽  
AQM Bazlur Rashid
Keyword(s):  
Relative Humidity ◽  
Key Words ◽  
Grain Quality ◽  
Control Variable ◽  
Bipolaris Sorokiniana ◽  
Leaf Blight ◽  
The Other ◽  
High Humidity ◽  
Head Blight

Effect of exposure to different duration of high humidity (5,10,15,20,25 & 30 days) on the development of head blight caused by Bipolaris sorokiniana in wheat was studied in vitro. Maximum leaf blight severity of 42.97% and head blight development of 87.53% caused by the pathogen were recorded for the infected plants incubated for a period of 30 days under condition of high humidity. The treatments did not differ significantly with respect to head blight development except the control. Variable effects of the treatments was observed on the grain quality. The highest diseased (black pointed and shriveled) grains of 62.27% were recorded in treatment 6 (30 days exposure) followed by treatment 5 (25 days exposure) with 48.01% diseased grains. There were no significant differences among the other treatments except the check. Key words: Humidity, head blight, leaf blight, Bipolaris sorokiniana, wheat.

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.

In vitro evaluation of antimicrobial peptides against Fusarium species

2009 ◽  
Vol 89 (4) ◽  
pp. 739-743 ◽  
Author(s):  
A Badea ◽  
F Eudes ◽  
R Graf ◽  
A Laroche ◽  
A E Berg ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Fusarium Head Blight ◽  
Key Words ◽  
Mycelial Growth ◽  
Fusarium Species ◽  
Common Species ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Head Blight

The in vitro activity of five antimicrobial peptides was evaluated against several Fusarium species that affect wheat in Canada. Among the peptides tested (10R, 11R, BMAP-18, MsrA2 and MsrA3) 10R was most effective against conidial germination, whereas MsrA2 showed activity against mycelial growth. Antimicrobial peptides 10R and MsrA2 were identified as potential candidates for engineering resistance against common species causing fusarium head blight in wheat. Key words: Antimicrobial peptides, fusarium head blight, conidia, mycelia

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.

scholarly journals What’s the relative humidity in tropical caves?

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0250396
Author(s):  
Luis Mejía-Ortíz ◽  
Mary C. Christman ◽  
Tanja Pipan ◽  
David C. Culver
Keyword(s):  
Global Warming ◽  
Relative Humidity ◽  
Large River ◽  
The Other ◽  
Quintana Roo ◽  
High Humidity ◽  
Dark Zone ◽  
Negative Effect ◽  
One Year ◽  
Strong Seasonality

Relative humidity (RH) was measured at hourly intervals for approximately one year in two caves at seven stations near Playa del Carmen in Quintana Roo, Mexico. Sistema Muévelo Rico is a 1.1 km long cave with 12 entrances and almost no dark zone. Río Secreto (Tuch) is a large river cave with more than 40 km of passages, and an extensive dark zone. Given the need for cave specialists to adapt to saturated humidity, presumably by cuticular thinning, the major stress of RH would be its deviation from saturation. RH in Río Secreto (Tuch) was invariant at three sites and displayed short deviations from 100% RH at the other four sites. These deviations were concentrated at the end of the nortes and beginning of the rainy season. Three of the sites in Sistema Muévelo Rico showed a similar pattern although the timing of the deviations from 100% RH was somewhat displaced. Four sites in Sistema Muévelo Rico were more variable, and were analyzed using a measure of amount of time of deviation from 100% RH for each 24 hour period. Strong seasonality was evident but, remarkably, periods of constant high humidity were not the same at all sites. In most Sistema Muévelo Rico sites, there was a detectable 24 hour cycle in RH, although it was quite weak in about half of them. For Río Secreto (Tuch) only one site showed any sign of a 24 hour cycle. The troglomorphic fauna was more or less uniformly spread throughout the caves and did not concentrate in any one area or set of RH conditions. Compared to temperature, RH is much more constant, perhaps even more constant than the amount of light. However, changes in RH as a result of global warming may have a major negative effect on the subterranean fauna.

Genotypic differences in chemical composition and ruminal degradability of oat hulls

2000 ◽  
Vol 80 (2) ◽  
pp. 377-379 ◽  
Author(s):  
R. K. Thompson ◽  
A. F. Mustafa ◽  
J. J. McKinnon ◽  
D. Maenz ◽  
B. Rossnagel
Keyword(s):  
Chemical Composition ◽  
Key Words ◽  
Dry Matter ◽  
The Other ◽  
Genotypic Differences ◽  
Oat Hulls ◽  
Acid Detergent Lignin ◽  
Ruminal Degradability

A study was conducted to determine differences in chemical composition and ruminal degradability of oat hulls derived from ten oat varieties. Hulls derived from AC Assiniboia had a lower (P < 0.05) acid detergent lignin (ADL) and a higher (P < 0.05) in vitro dry matter disappearance (IVDMD) relative to the other nine varieties. Effective ruminal degradability of neutral (NDF) and acid (ADF) detergent fiber for AC Assiniboia hulls were higher (P < 0.05) than those of Calibre hulls and similar to those of Calibre straw. Key words: Oat hulls, chemical composition, ruminal degradability

scholarly journals What's the relative humidity in tropical caves?

2021 ◽  
Author(s):  
Luis Mejia-Ortiz ◽  
Mary C. Christman ◽  
Tanja Pipan ◽  
David C Culver
Keyword(s):  
Relative Humidity ◽  
Similar Pattern ◽  
Rainy Season ◽  
Large River ◽  
The Other ◽  
Quintana Roo ◽  
High Humidity ◽  
Dark Zone ◽  
One Year ◽  
Strong Seasonality

Relative humidity (RH) was measured at hourly intervals for approximately one year in two caves at seven stations near Playa del Carmen in Quintana Roo, Mexico. Sistema Muévelo Rico is a 1.1 km long cave with 12 entrances and almost no dark zone.  Río Secreto (Tuch) is a large river cave with more than 40 km of passages, and an extensive dark zone. Given the need for cave specialists to adapt to saturated humidity, presumably by cuticular thinning, the major stress of RH would be its deviation from saturation. RH in Río Secreto (Tuch) was invariant at three sites and displayed short deviations from 100% RH at the other four sites.  These deviations were concentrated at the end of the nortes and beginning of the rainy season. Three of the sites in Sistema Muévelo Rico showed a similar pattern although the timing of the deviations from 100% RH was somewhat displaced.  Four sites in Sistema Muévelo Rico were more variable, and were analyzed using a measure of amount of time of deviation from 100% RH for each 24 hour period.  Strong seasonality was evident but, remarkably, periods of constant high humidity were not the same at all sites.  In most Sistema Muévelo Rico sites, there was a detectable 24 hour cycle in RH, although it was quite weak in about half of them.  For Río Secreto (Tuch) only one site showed any sign of a 24 hour cycle. The troglomorphic fauna was more or less uniformly spread throughout the caves and did not concentrate in any one area or set of RH conditions. Compared to temperature, RH is much more constant, perhaps even more constant than the amount of light.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

ALDOSTERONE STIMULATION IN VITRO

1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Ammonium Chloride ◽  
Human Urine ◽  
Incubation Medium ◽  
The Other ◽  
Ammonium Ions ◽  
Response Curves ◽  
Urine Extract ◽  
Similar Dose ◽  
Aldosterone Production

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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