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1.
Progress in leaf protoplast isolation and culture from virus-free axenic shoot cultures of Vitis vinifera L. 总被引:1,自引:0,他引:1
Theodoropoulos P. A. Roubelakis-Angelakis K. A. 《Plant Cell, Tissue and Organ Culture》1990,20(1):15-23
Axenic shoot cultures of virus-free Vitis vinifera L. cv. Soultanina were a highly efficient source for isolation of viable protoplasts. Optimum results were obtained with leaves of 50–100 mg fresh weight, leaf discs of 0.7 cm in diameter, 100 and 15 U ml-1 Cellulase R-10 and Macerozyme R-10, respectively, and 18 h reaction time in either light or in darkness. Protoplast yield was approx. 25×106 viable protoplasts per g fresh weight and their size ranged from 12 to 44 m. During a 20-day culture period, the maximum survival rate obtained was approx. 40%. A plating density of 10×105 protoplasts per ml resulted in increased survival rates. Various growth regulators and glutamine did not significantly improve survival rates of protoplasts, whereas extract from coconut added to the culture medium caused an increase in the survival rates of protoplasts. Cell elongation at a significant rate and divisions were observed. [14C]glucose uptake was studied as an index of cell membrane integrity and functioning. Uptake rate of glucose by protoplasts was linear for up to 60 min, fully inhibited by NaN3, with an optimum pH of 4.8. Protoplasts 24 h old exhibited significantly lower rates of glucose uptake. 相似文献
2.
Seed transmission of turnip yellow mosaic virus in winter turnip and winter oilseed rapes 总被引:1,自引:0,他引:1
This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings. 相似文献
3.
TERESA MARYAKA HALSZKA OSMÓLSKA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1979,12(3):265-273
Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed. 相似文献
4.
K. C. Katsirdakis K. A. Roubelakis-Angelakis 《In vitro cellular & developmental biology. Plant》1992,28(2):90-96
Summary To identify possible reasons that may contribute to recalcitrance in plant protoplasts, the time course of new cell wall deposition
was studied by scanning electron microscopy in protoplasts of a recalcitrant species, the grapevine. Results showed that microfibrils
were developed after 2 days of culture, that complete cell wall formation occurred on Day 6 to 7 of protoplast culture, and
its ultrastructural appearance was identical to that of grapevine leaf-derived callus cells. In addition, a comparative study
was undertaken on [U-14C]glucose uptake and incorporation in ethanol-soluble, cellulosic, and noncellulosic polysaccharide fractions in protoplasts
of grapevine and of a readily regenerating species, tobacco, during culture. There was a significantly higher [U-14C]glucose uptake by tobacco than by grapevine protoplasts. The label distribution in the ethanol-soluble, cellulosic, and
noncellulosic fractions of newly synthesized cell walls differed quantitatively between the two species. In particular, the
labeled glucose incorporated in the noncellulosic cell wall fraction was threefold greater in tobacco than in grapevine protoplasts.
Differences were also revealed in the monosaccharide composition of this fraction between the two species. Addition of dimethyl
sulfoxide to the culture medium resulted in a dramatic increase in [U-14C]glucose uptake by grapevine protoplasts, whereas it exhibited a limited effect in tobacco protoplasts. It showed no effect
on the ultrastructural characteristics of new cell wall nor on the incorporation rate of labeled glucose in the cellulosic
and noncellulosic cell wall fractions. 相似文献
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6.
The paper presents multiplex panels of polymorphic microsatellites for two closely related cryptic species Pipistrellus pipistrellus and Pipistrellus pygmaeus. We tested the cross‐species amplification of 34 microsatellite loci, originally developed for five vespertilionid bat species. Ten and nine polymorphic loci in P. pipistrellus (mean number of alleles per locus = 10.5) and P. pygmaeus (8.1), respectively, in three multiplex polymerase chain reactions per species were amplified. All loci can be analysed in a single fragment analysis and can be used as markers to the study of evolution and the ecology of structured populations of socially living bats. 相似文献
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9.
Reduced activity of antioxidant machinery is correlated with suppression of totipotency in plant protoplasts 下载免费PDF全文
We previously showed that during protoplast isolation, an oxidative burst occurred and the generation of active oxygen species was differentially mediated in tobacco (Nicotiana tabacum) and grapevine (Vitis vinifera), accompanied by significant quantitative differences (A.K. Papadakis, K.A. Roubelakis-Angelakis [1999] Plant Physiol 127: 197-205). We have now further tested if the expression of totipotency in protoplasts is related to the activity of cellular antioxidant machinery during protoplast culture. Totipotent (T) tobacco protoplasts had 2-fold lower contents of intracellular O2*- and H2O2 and 7-fold lower levels of O2*- and H2O2 in the culture medium, compared with non-totipotent (NT) tobacco protoplasts. Addition of alkaline dimethylsulfoxide, known to generate O2*-, resulted in isolation of tobacco protoplasts with reduced viability and cell division potential during subsequent culture. Active oxygen species levels decreased in tobacco and grapevine protoplasts during culturing, although higher contents of O2*- and H2O2 were still found in NT- compared with T-tobacco protoplasts, after 8 d in culture. In T-tobacco protoplasts, the reduced forms of ascorbate and glutathione predominated, whereas in NT-tobacco and grapevine protoplasts, the oxidized forms predominated. In addition, T-tobacco protoplasts exhibited severalfold lower lipid peroxidation than NT-tobacco and grapevine protoplasts. Furthermore, several antioxidant enzyme activities were increased in T-tobacco protoplasts. Superoxide dismutase activity increased in tobacco, but not in grapevine protoplasts during culturing due to the increased expression of cytoplasmic Cu/Zn-superoxide dismutase. The increase was only sustained in T-tobacco protoplasts for d 8. Together, these results suggest that suppressed expression of totipotency in protoplasts is correlated with reduced activity of the cellular antioxidant machinery. 相似文献
10.
J?Craig CohenEmail author Lennart?KA?Lundblad Jason?HT?Bates Michael?Levitzky Janet?E?Larson 《BMC genetics》2004,5(1):21