Germination of Orobanche crenata seeds, as influenced by conditioning temperature and period

1993 ◽  
Vol 71 (6) ◽  
pp. 786-792 ◽  
Author(s):  
M. J. van Hezewijk ◽  
A. P. van Beem ◽  
J. A. C. Verkleij ◽  
A.H. Pieterse
Keyword(s):  
Key Words ◽  
Optimum Temperature ◽  
Orobanche Crenata ◽  
Parasitic Weed ◽  
Secondary Dormancy ◽  
Conditioning Period ◽  
Conditioning Temperature ◽  
Seeds Germination ◽  
Tetrazolium Test

The effects of conditioning temperature and length of the conditioning period on germination of seeds of the parasitic weed Orobanche crenata were investigated in vitro. Seed samples from Syria and Egypt, collected in various years, were compared. Optimum temperature for conditioning was 15–20 °C for Syrian seeds and 20 or 15–20 °C for Egyptian seeds. At 20 °C a conditioning period of 18 days was required for maximum germination. When conditioning at 20 °C was prolonged beyond 7 weeks, germination decreased. This effect was more pronounced for Egyptian seeds than for Syrian seeds. Germination of Syrian seeds was strongly reduced after conditioning for more than 4 weeks at 15 or 10 °C. A stepwise decrease in temperature during conditioning did not enhance this effect. The results of a tetrazolium test indicated that the seeds most probably did not die but developed secondary dormancy. Key words: Orobanche, germination, conditioning, temperature, dormancy.

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.

scholarly journals Methodology of the tetrazolium test for identifying viable seeds of orchids of the genus Cattleya native to the Brazilian Cerrado

2021 ◽  
Vol 42 (3) ◽  
pp. 1351-1360
Author(s):  
Luan Marlon Ribeiro ◽  
◽  
José Carlos Sorgato ◽  
Jackeline Schultz Soares ◽  
Jéssica Celeste Mônico Ramos ◽  
...  
Keyword(s):  
Room Temperature ◽  
Germination Percentage ◽  
Seed Banks ◽  
Brazilian Cerrado ◽  
Randomized Design ◽  
Conditioning Temperature ◽  
Completely Randomized Design ◽  
Viable Seeds ◽  
Tetrazolium Test

Orchids need measures for conservation of their species, among them the creation of seed banks. This study analyzes suitable methodologies to identify the viability of Cattleya seeds through the tetrazolium test. Seeds of Cattleya nobilior Rchb. and Cattleya walkeriana Gardn. were submitted to three preconditioning: no soaking (control); sucrose (10%); or distilled water. After 24 hours, they were submitted to tetrazolium solution with three types of conditioning: oven (40 °C); water bath (40 °C); or room temperature. Subsequently, the percentage of viable seeds (VS) was calculated and in vitro sowing was carried out. Germination percentage (G) was determined after 45 days. A completely randomized design was used for each species studied, with treatments arranged in a 3x3 factorial scheme (three preconditioning and three conditioning), with eight replicates of one tube each. The experiment was performed in duplicate. The highest viability values found in the tetrazolium test were close to those of germination (C. nobilior: VS = 88% e G = 97%; C. walkeriana: VS = 88% e G = 95%) for Cattleya species native to the Cerrado. The conditioning at ambient temperature had a greater effect on seed visualization for both species studied, suggesting that the tetrazolium test should be performed at this conditioning temperature.

DETERMINATION OF AFTER-RIPENING PERIOD AND HORMONAL RESPONSE OF OROBANCHE SOLMSII C.D. CLARKE SEEDS

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Bista ◽  
G. B. Khattri ◽  
B. D. Acharya ◽  
S. C. Srivastava
Keyword(s):  
Growth Hormone ◽  
Seed Germination ◽  
Key Words ◽  
Incubation Period ◽  
Seed Set ◽  
Summer Season ◽  
Conditioning Period ◽  
Root Parasite ◽  
One Year

To find out the ability of Orobanche seeds to germinate immediately after seed set, seeds were germinated periodically at an interval of three months for one year in GR24. Some Orobanche seeds were capable of germination immediately after seed set but most required about nine months as after ripening or incubation period to be able to germinate. The phenomenon of after ripening in Orobanche seeds could be taken as an ecological measure to dormant over following unfavorable wet summer season. The growth hormone studies on Orobanche seed germination have shown that GA3 at a concentration of 100 ppm substantially enhanced seed germination when applied during pre-conditioning period. NAA showed some stimulatory effect at 0.5 - 1.0 ppm when applied during post-conditioning period but the hormone if applied during pre-conditioning period inhibited the germination. Kinetin failed to stimulate the germination at all the concentrations tested. Key words: Germination, root-parasite, hormone. Ecoprint Vol.11(1) 2004.

scholarly journals GLUCOSE CONSUMPTION AND LACTIC ACID PRODUCTION BY ERYTHROCYTES FROM DOUBLE-MUSCLED CATTLE

1982 ◽  
Vol 62 (3) ◽  
pp. 751-757 ◽  
Author(s):  
J. A. BASARAB ◽  
R. T. BERG ◽  
J. R. THOMPSON
Keyword(s):  
Lactic Acid ◽  
Key Words ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Age Groups ◽  
Phenotypic Expression ◽  
Glucose Consumption ◽  
Molar Ratio ◽  
Breed Group

The in vitro glucose consumption and lactic acid production by erythrocytes from 20 cattle of a Beef Synthetic (SY) breed group and 25 cattle of a double-muscled (DM) breed group were determined. There were three age groups and two sexes within each breed group. Animals within the DM breed group were categorized as either phenotypically normal- to moderate-muscled (DM carriers) or extreme-muscled (extreme DM) based on the phenotypic expression of the double-muscling trait and on their breeding history. Both DM phenotypes had higher (P < 0.01) erythrocyte glucose consumption and lactic acid production than normal-muscled, noncarrier cattle of the SY breed group. Extreme DM cattle were not different (P > 0.05) in either their erythrocyte glucose consumption or lactic acid production compared with DM carriers. No difference (P > 0.05) due to breed or phenotype was observed in the molar ratio of lactic acid produced to glucose consumed by erythrocytes. These results suggest that carriers of the Double Muscled Syndrome, regardless of phenotypic expression of the double-muscling trait, have a higher rate of erythrocyte glycolysis than normal cattle. Key words: Cattle, double muscled, erythrocyte, glucose, lactic acid

scholarly journals Infection Potential of Pleospora allii and Evaluation of Methods for Reduction of the Overwintering Inoculum of Brown Spot of Pear

Plant Disease ◽  
2006 ◽  
Vol 90 (12) ◽  
pp. 1511-1516 ◽  
Author(s):  
Isidre Llorente ◽  
Albert Vilardell ◽  
Emilio Montesinos
Keyword(s):  
Biological Control ◽  
Brown Spot ◽  
Control Methods ◽  
Optimum Temperature ◽  
Chemical Methods ◽  
Stemphylium Vesicarium ◽  
Mechanical Methods ◽  
Pleospora Allii ◽  
Evaluation Of Methods

The capacity for germination and pathogenicity to pear leaves of ascospores of Pleospora allii, the teleomorph of Stemphylium vesicarium, causal agent of brown spot of pear, were studied in vitro. Most ascospores germinated within 1 h at temperatures between 15 and 20°C, and the optimum temperature for germination was 18.9°C. Infections developed on wounded and non-wounded detached pear leaves, but were more frequent on wounded leaves. The minimum infective dose was one ascospore per wound. Biological, chemical, and mechanical methods for decreasing overwintering inoculum of P. allii were evaluated. Ascospores were discharged from March to May, depending on the orchard and year. Leaf shredding or removal were the most effective methods of reducing overwintering inoculum. Biological control methods based on application of Thichodermasp. formulations were partially effective. Chemical methods based on copper and urea treatments were ineffective.

Results of an experimental study of hydrogel drainage containing ranibizumab in antiglaucoma operations

2021 ◽  
pp. 63-67
Author(s):  
I.I. Khusnitdinov ◽  
Keyword(s):  
Experimental Study ◽  
Hyaluronic Acid ◽  
Key Words ◽  
Experimental Research ◽  
Experimental Studies ◽  
Glaucoma Surgery ◽  
Control Group ◽  
Morphological Studies

Purpose. Еxperimental substantiation of the effectiveness of biocompatible biodegradable hydrogels based on hyaluronic acid and chitosan succinate as a carrier of ranibizumab in antiglaucoma operations. Material and methods. Hydrogel drainage (HD) was obtained immediately before surgery. A solution of ranibizumab (0.23 ml) was mixed with a solution of hyaluronic acid dialdehyde (0.5 ml), then a solution of chitosan succinate (0.5 ml) was added. Experimental studies were performed in 12 (12 eyes) healthy rabbits. The first group consisted of 6 eyes – 0.187 ml of ranibizumab per 1 ml of gel. In the control group, HD was used intraoperatively without the addition of ranibizumab (6 eyes). Morphological studies were performed on 7th, 21st, and 42nd days. Results. In experimental studies in vitro and in vivo, it was proved that ranibizumab, administered as a part of 0.1 ml of hydrogel drainage in the antiglaucoma surgery area is released within 3 weeks and suppresses vascularization, scarring of the operating area, and preserves the intrascleral cavity. The optimal concentration of ranibizumab was selected-0.02 ml in 0.1 ml of gel. Conclusion. The safety and effectiveness of the use of hydrogel drainage with ranibizumab based on hyaluronic acid dialdehyde and chitosan succinate in anti-glaucoma operations has been proven. Key words: experimental research, hydrogel drainage, ranibizumab, glaucoma surgery.

scholarly journals Effects of Growth Regulators on In vitro Propagation and Tuberization of Four Dioscorea Species

1970 ◽  
Vol 18 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Md. Tariqul Islam ◽  
E. R. Joachim Keller ◽  
D. Philibert Dembele
Keyword(s):  
Key Words ◽  
Growth Regulators ◽  
Plant Tissue ◽  
In Vitro Propagation ◽  
In Vitro Production ◽  
Dioscorea Species ◽  
Vitro Production ◽  
Species Being ◽  
Nodal Culture

Nodal explants of 12 accessions from four species of yam (Dioscorea spp.) were cultured for six weeks on MS to evaluate the influence of IAA, Kn, NAA and BAP on the production of leaves and microtubers. Four Dioscorea polystachya Turcz., three each of D. bulbifera L. and D. sansibarensis Pax. and two D. japonica Thunb. accessions were used. Five and 10 mg/l of Kn along with IAA and sucrose, and 0.2 and 0.5 mg/l of NAA, sucrose and with or without BAP were used in four treatments. The accessions Yam 23 and Yam 25 of D. sansibarensis failed to initiate any leaf under four treatments. The remaining accessions produced 0.11 to 1.76 leaves per explant. The medium containing IAA with higher concentration of Kn (10 mg/l) and 3% sucrose was found to be best for in vitro production of leaf (0.71/explant) and the most productive species was D. japonica (1.36), followed by D. polystachya (1.19/explant). At the same culture period, Yam 16 of D. bulbifera failed to initiate any microtuber at IAA with Kn, and NAA with or without BAP. The remaining accessions produced 0.09 to 1.15 microtubers per explant. Lower concentration of Kn (5 mg/l) with IAA and sucrose was favourable for producing microtubers (0.61/explant on an average), the best species being D. sansibarensis (1.27) followed by D. japonica (0.59/ explant). Finally, the presence of BAP adversely affected the production of microtuber among Dioscorea species. Key words: Dioscorea spp., Microtuber, Nodal culture, Propagation D.O.I. 10.3329/ptcb.v18i1.3260 Plant Tissue Cult. & Biotech. 18(1): 25-35, 2008 (June)

scholarly journals In vitro Propagation of Solanum capsicoides All. – An Important Therapeutic Agent 'Kantakari'

1970 ◽  
Vol 20 (2) ◽  
pp. 179-184
Author(s):  
N.P. Anish ◽  
M.G. Rajesh ◽  
Jiby Elias ◽  
N. Jayan
Keyword(s):  
Survival Rate ◽  
Key Words ◽  
Plant Tissue ◽  
In Vitro Propagation ◽  
Therapeutic Agent ◽  
Shoot Tip ◽  
Shoot Induction ◽  
Half Strength ◽  
Shoot Tip Explants

Shoot tip explants from in vitro germinated seedlings of Solanum capsicoides All. inoculated on MS containing 2 mg/l BA produced maximum shoot induction response (26 shoots per explant). Rooting of the microshoots (19.4 roots per explant) was obtained better in half strength of MS supplemented with NAA (0.5 mg/l). Well rooted plantlets were successfully hardened with 80 per cent survival rate.   Key words: Solanum capsicoides, Propagation, Therapeutic agent   D.O.I. 10.3329/ptcb.v20i2.6912   Plant Tissue Cult. & Biotech. 20(2): 179-184, 2010 (December)

scholarly journals Biochemistry of postharvest spoilage of sweet potato (Ipomoea batatas L.). 2. Comparison of cellulolytic enzyme production in cultures and fungi-infected sweet potato tubers

2006 ◽  
pp. 48-57
Author(s):  
R. C. Ray
Keyword(s):  
Sweet Potato ◽  
Enzyme Production ◽  
Ipomoea Batatas ◽  
Rhizopus Oryzae ◽  
Cellulose Synthesis ◽  
Cellulolytic Enzyme ◽  
Optimum Temperature ◽  
Potato Tubers

The study was conducted to determine the production in vitro and in vivo of cellulases by Botrydiplodia theobromae and Rhizopus oryzae. Isolates of these organisms were obtained from the postharvest decay of sweetpotato tubers. Results revealed that B. theobrornae and R. oryzae which were isolated from postharvest spoilage of sweetpotato tubers produced endo-13-1,4-glucanase and exo-V-1 ,4-glucanase in culture and in fungi-infected tissues of sweetpotato tubers. The optimum temperature and pH for cellulose synthesis and activity were 30°C and pH 6.5, respectively.

An attempt at sperm-mediated gene transfer in mice and chickens

1991 ◽  
Vol 71 (2) ◽  
pp. 287-291 ◽  
Author(s):  
J. S. Gavora ◽  
B. Benkel ◽  
H. Sasada ◽  
W. J. Cantwell ◽  
P. Fiser ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Gene Transfer ◽  
Transgenic Mice ◽  
Key Words ◽  
Plasmid Dna ◽  
Dna Transfer ◽  
Laboratory Mice ◽  
Vitro Fertilization ◽  
Bacterial Plasmid

Experiments were carried out to transform laboratory mice and domestic chickens by use of sperm incubated with bacterial plasmid DNA. Following demonstration of "uptake" of such DNA by sperm of both species, attempts were made to replicate a previously published procedure (Lavitrano et al. 1989, Cell 57: 717–723) for producing transgenic mice through in vitro fertilization (IVF). Also, female mice and hens were inseminated (AI) with sperm which had been incubated in a DNA solution. Such incubation did not influence the fertility or hatchability of the hens' eggs. However, no transformed progeny were detected among 45 mice produced by IVF or among 69 mice and 470 chickens produced by AI. Key words: Sperm-mediated DNA transfer, mice, chickens

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