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1.
Stability of tissue culture medium pH as a function of autoclaving,time, and cultured plant material
Robert M. Skirvin Mel C. Chu Mary L. Mann Heather Young Joseph Sullivan Thomas Fermanian 《Plant cell reports》1986,5(4):292-294
Autoclaving is a standard procedure for sterilizing nutrient media for plant tissue cultures. Most tissue cultures are grown at pH 5.2 to 5.8 with pH adjustments being made prior to autoclaving. This paper reports that there are significant differences between initial pH levels and pH levels following autoclaving, particularly in the pH range of 5.7 to 8.5. This effect is noted with and without agar. In addition, we report that with time the pH of the medium drifts into the acid range. When Cucumis callus was added to the medium, the pH was changed significantly within 48 hours. The amount and direction (increase or decrease of pH) was significantly correlated with the original pH. This suggests that researchers should be wary of the true pH situation in their medium. In addition, in publications authors should specify whether their medium pH value was determined before or after autoclaving. 相似文献
2.
E. Chevreau R. M. Skirvin H. A. Abu-Qaoud S. S. Korban J. G. Sullivan 《Plant cell reports》1989,7(8):688-691
To develop an adventitious regeneration system for pear cultivars, several experiments were conducted with 2 cultivars of Pyrus communis L. (Seckel and Louise Bonne) and one cultivar of P. bretschneideri Rehd. (Crystal Pear). Half-leaves, taken from shoots proliferating on Lepoivre medium, were plated in petri-dishes on medium supplemented with various combinations of cytokinins and auxins. Cultures of the above cultivars had been established from mature trees. Among the growth regulators tested, thidiazuron (TDZ), combined with naphthalene-acetic acid (NAA), was the most efficient for stimulation of adventitious shoots. The optimum level of TDZ was about 3 uM; shoot regeneration was observed over a wide range of TDZ and NAA concentrations (0.5 to 5 uM and 2.5 to 13 um, respectively). Among different macronutrient compositions, 1/2 and 1/4 Murashige and Skoog were the most effective. Sucrose concentrations (10 to 50 g L-1) had a linear significant effect on shoot regeneration of Crystal Pear.Abbreviations BAP
6-benzylaminopurine
- IBA
indole-3-butyric acid
- NAA
a-naphthaleneacetic acid
- NoA
2-naphthoxyacetic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- TDZ
thidiazuron (N-phenyl-N'-1,2,3-thidiazol-5-ylurea)
- MS
Murashige and Skoog (1962) macroelements
- L
Lepoivre (Quoirin and Lepoivre, 1977) macroelements 相似文献
3.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
4.
Mohamed Kouider Randal Hauptmann Jack M. Widholm Robert M. Skirvin Safi S. Korban 《Plant cell reports》1984,3(4):142-145
Protoplasts could be successfully isolated and cultured from callus and suspension cultures of Malus xdomestica cv. Jonathan. Protoplast-derived colonies were recovered when the osmoticum (glucose) was gradually reduced in semi-solid 8p medium or by the use of feeder plates. Formation of embryo-like structures was induced from the protoplast-derived callus on media supplemented with IAA and BA. These structures formed roots but plants failed to develop. Protoplasts could be isolated from leaves, but not from stems or petioles. The leaf protoplasts failed to divide.List of abbreviations BA
benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- ABA
abscisic acid
- IAA
indole acetic acid 相似文献
5.
Skirvin DJ Kravar-Garde L Reynolds K Jones J Mead A Fenlon J 《Bulletin of entomological research》2007,97(3):309-315
Two experiments were done to examine the predation of thrips, and the movement of Orius laevigatus Fieber and Neoseiulus cucumeris (Oudemans) in the presence and absence of two supplemental food sources, pollen and the fungus Trichoderma viride. The presence of pollen led to a 55% reduction in predation of the thrips by N. cucumeris and a 40% reduction in thrips predation by O. laevigatus, in experiments using single predators. The presence of fungus had no significant effect on thrips predation by either of the natural enemy species. Movement of the natural enemies was examined in a multiple predator experiment, and this showed that O. laevigatus was more likely to remain on the plant in the presence of thrips and when supplemental food, either pollen or fungus, was present. For N. cucumeris, there was no association between the presence of thrips and the mite, with the majority of the mites being found on the leaves where pollen was present. Although the single and multiple predator experiments were done at different times, the indications are that the predation rates of the N. cucumeris do not differ greatly between the two experiments, suggesting that there may be a potential interference effect between the mites, which is not present for O. laevigatus. The significance of these results for the use of supplemental food sources in biological control is discussed. 相似文献
6.
The effect of temperature on the functional response of Phytoseiulus persimilis (Acari: Phytoseiidae) 总被引:1,自引:0,他引:1
Environmental variables, such as temperature, are important in determining the efficiency of biological control in ornamental crops. This paper examines the effect of temperature on the functional response of adult female Phytoseiulus persimilis to eggs of the spider mite, Tetranychus urticae. The functional response was determined using a new functional response assay technique with plant stems as an arena, rather than leaf discs. The use of plant stems allows the influence that plant structure has on predation to be incorporated into the assay. Control assays were also used (without predators) to estimate natural losses of prey. The data were analysed using a binomial model, with the use of Abbot's formula to correct for the losses in the controls. A combined equation to describe the effect of temperature and prey density on the predation rate of Phytoseiulus persimilis was derived. The results showed that more prey are eaten as the temperature increases from 15 degrees C to 25 degrees C, but the number of prey eaten then declines at 30 degrees C, although not to the levels seen at 20 degrees C. The implication of these results for biological control in ornamental crops, where the temperature can often exceed 30 degrees C, is discussed. 相似文献
7.
Muma JB Lund A Siamudaala VM Munang'andu HM Munyeme M Matope G Nielsen K DJønne B Godfroid J Tryland M Skjerve E 《Journal of wildlife diseases》2010,46(4):1063-1069
One of the diseases of veterinary and public health importance affecting the Kafue lechwe (Kobus leche kafuensis) on the Kafue flats is brucellosis, for which only scant information is available. During the 2003 (October), 2004 (December), and 2008 (July-December) hunting seasons in the Kafue flats, we conducted a study to determine the seroprevalence of Brucella spp. in the Kafue lechwe and to evaluate serologic tests for detection of Brucella spp. antibodies in lechwe. The Rose Bengal Test (RBT), competitive enzyme-linked immunosorbent assay (cELISA), and fluorescence polarization assay (FPA) were used. A total of 121 Kafue lechwe were hunted for disease investigations in 2003, 2004, and 2008 in the Kafue Flat Game Management Area. Of these, 21.6%, (95% confidence interval [CI]: 14.2-29.1%) had detectable antibodies to Brucella spp. The Kafue lechwe in Lochnivar National Park had higher antibody results than those in Blue Lagoon National Park (odds ratio=3.0; 95% CI: 0.94-9.4). Infection levels were similar in females (21.6%) and males (21.7%). Results were similar among RBT, FPA, cELISA tests, suggesting that these could effectively be used in diagnosing brucellosis in the Kafue lechwe. Our study demonstrates the presence of Brucella infections in the Kafue lechwe in two national parks located in the Kafue flats and further highlights the suitability of serologic assays for testing the Kafue lechwe. Because the Kafue lechwe is the most hunted wildlife species in Zambia, hunters need to be informed of the public health risk of Brucella spp. infection. 相似文献
8.
N. Ali R. M. S. Mulwa M. A. Norton R. M. Skirvin 《Plant Cell, Tissue and Organ Culture》2007,91(3):295-298
Controlling contamination in vitro is one of the basic requirements for successful tissue culture technology. In preliminary
studies, in vitro contamination of guava seeds was almost 100%, even when disinfested with bleach. To overcome this problem,
we developed a unique method to control contamination using bleach and strong acids. Submerging guava seeds in 10% HCl for
24–72 h followed by a 30 min treatment with 10% bleach (NaOCl) reduced contamination rates from 98 to 0%. Substituting 5%
H2SO4 for 12 h for 10% HCL gave similar results. In addition to eliminating contamination, acid-treated seeds germinated faster
in vitro than control seeds germinated in a greenhouse (15 vs. 40 days, respectively). 相似文献
9.
Susan DJ Chapple Anna M Crofts S Paul Shadbolt John McCafferty Michael R Dyson 《BMC biotechnology》2006,6(1):49-15
Background
A variety of approaches to understanding protein structure and function require production of recombinant protein. Mammalian based expression systems have advantages over bacterial systems for certain classes of protein but can be slower and more laborious. Thus the availability of a simple system for production and rapid screening of constructs or conditions for mammalian expression would be of great benefit. To this end we have coupled an efficient recombinant protein production system based on transient transfection in HEK-293 EBNA1 (HEK-293E) suspension cells with a dot blot method allowing pre-screening of proteins expressed in cells in a high throughput manner. 相似文献10.