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81.
Rescifina A Chiacchio U Iannazzo D Piperno A Romeo G 《Journal of agricultural and food chemistry》2010,58(22):11876-11882
Complexes of β-cyclodextrin (β-CD) and caffeine (Caf) with biophenols present in olive and olive oil (tyrosol, hydroxytyrosol, homovanillic acid, 3,4-dihydroxyphenylacetic acid, and protocatechuic acid) were investigated by NMR spectroscopy and thermodynamical-molecular dynamic studies to verify the formation of supermolecular aggregates. The obtained results indicated that the investigated biophenols form inclusion complexes with β-CD in a molar ratio of 1:1 in aqueous solution having binding constant values from 10- to 40-fold bigger than those of the corresponding complexes with Caf. Then, β-CD preferentially encloses the biophenol molecule, decreasing its bitter taste and, at the same time, preserving it against chemical and physical decomposition reactions that occur during storage. 相似文献
82.
In order to observe the spatial phosphorus (P) fractions transformations in sediments in relation to bacterial abundance and enzyme hydrolysing organic P-alkaline phosphatase (APA), samples from 35 stations from eutrophic Sulejow Reservoir were taken in spring after flood and in summer after cyanobacterial bloom breakdown. The results show pronounced fluctuations: decrease of average total P in sediments, despite organic matter delivery after cyanobacterial bloom, in parallel with increase of labile P (8.3%) and Ca-bounded P (16.6%) fractions and decline of organic P fraction (28.5%). Higher alkaline activity in sediments in the spring delivered nutrients to water column and supported cyanobacterial bloom development during the summer. Positive correlation between APA and organic P (r?=?0.37, p?<?0.01, n?=?70) and negative with labile inorganic P (r?=??0.44, p?<?0.01, n?=?70) in sediments proved significant role of the APA in phosphorus transformation in sediments and internal loading in the reservoir. During summer, APA was significantly related to bacterial number (r?=?0.36, p?<?0.01, n?=?35) and bacterial abundance was correlated to organic matter content (r?=?0.36, p?<?0.01, n?=?35). Such pattern of temporal variations of P transformation in sediments indicates order of solutions for enhancement of recultivation effects of eutrophic dam reservoirs: (1) reduction of organic matter supply in spring and (2) sediment inactivation during summer. 相似文献
83.
Anna Lisek Danuta Kucharska Agnieszka Głowacka Elżbieta Rozpara 《The Journal of Horticultural Science and Biotechnology》2017,92(5):484-492
The sour cherry is known to exhibit the phenomenon of gametophytic self-incompatibility which prevents self-fertilization. In sour cherry, besides self-incompatible cultivars, there often occur self-compatible cultivars. This is due to the occurrence of natural mutations of the S-RNase or SFB genes and, consequently, loss of functionality of S-alleles. Here we present the results of the identification of S-haplotypes of 21 cultivars of sour cherry from various regions of Europe. The analyses were performed using methods based on the amplification of intron I and intron II of the S-RNase gene and fragments specific to the individual alleles of the S-RNase or SFB genes. The tested cultivars were found to contain 15 S-haplotypes: S1, S1?, S4, S6, S6m, S6m2, S9, S12, S13, S13?, S26, S35, S36a, S36b, and S36b2. The most frequently occurring S-haplotypes were S13? (61.9%), S36a (57.1%), and S26 (47.6%). On the basis of the results, 17 of the 21 cultivars were deduced to be self-compatible. The results will be of use in the production of sour cherry fruit by facilitating the selection of suitable pollinating cultivars. The results are also expected to be useful in the breeding of new cultivars of sour cherry when selecting genotypes for crosses. 相似文献
84.
Maria Holmberg Anu Akujärvi Saku Anttila Lauri Arvola Irina Bergström Kristin Böttcher Xiaoming Feng Martin Forsius Inese Huttunen Markus Huttunen Yki Laine Heikki Lehtonen Jari Liski Laura Mononen Katri Rankinen Anna Repo Vanamo Piirainen Pekka Vanhala Petteri Vihervaara 《Landscape Ecology》2015,30(3):561-577
85.
86.
New aspects of soybean somatic embryogenesis 总被引:4,自引:0,他引:4
Somatic embryo formation from immature cotyledons was improved in the following ways: by cutting into sections, supplementing culture media with spermine and using solid/liquid/solid type of culture. Cut cotyledons of the eight genotypes examined expressed a higher ability for somatic embryogenesis than whole cotyledons. Of the three polyamines tested, spermine considerably stimulated and putrescine slightly inhibited induction of somatic embryos. The ability of embryoid formation on medium with spermidine depended on the genotype. The solid/liquid/solid type of culture was better than the continuous solid culture. The best nitrogen ion content for the subculture of somatic embryos was 10 mM NH4NO3 and 30 mM KNO3. The possibility of using these modifications in Agrobacterium transformation is discussed. 相似文献
87.
Anna Pretova Norbert C.A. de Ruijter André A.M. van Lammeren Jan H.N. Schel 《Euphytica》1992,65(1):61-69
Summary The capacity of the maize genotype 4c1 to regenerate microcalli and embryos from cultured microspores has been examined by comparing various cold pretreatments and culture media, using microspores and pollen at different stages of development. Viability of cultured cells was tested with FDA and their development was traced with light and fluorescence microscopy using DAPI as a nuclear dye.It was found that a pre-incubation of dissected flowers floating in a liquid nutrient medium at 8°C during 10–14 days was most successful for the induction of cell division. Among the developmental stages tested only the microspores appeared to regenerate. Subculture at 25°C in the same liquid medium, supplemented with 0.1 mg/l TIBA, gave highest rates of microspore division, i.e. up to 70% at 4 to 6 days of culture.All pathways described earlier for maize androgenic embryogenesis were observed within the 4c1 genotype. Symmetric divisions occurred in cultured microspores but most frequently asymmetric divisions lead to the formation of microcalli within 12 days of culture. In at least 60% of all dividing microspores cells were derived from the generative nucleus. Microcalli further developed either into loose or compact calli. Compact calli formed embryo-like structures.Abbreviations DAPI
4,6-diamidino-2-phenylindole
- Dicamba
3,6-dichloro-2-methoxy benzoic acid
- 2,4D
2,4 dichlorophenoxyacetic acid
- FDA
fluorescein diacetate
- PAA
phenylacetic acid
- TIBA
2,3,5-triiodobenzoic acid
- YP medium
Yu-Pei basal salt medium 相似文献
88.
PPR‐B‐31: a new maintainer allele in the male‐fertility restorer gene of radish (Raphanus sativus) Ogura cytoplasm 下载免费PDF全文
Anna Hawliczek‐Strulak Grzegorz Bartoszewski Renata Słomnicka Aleksandra Korzeniewska Régine Delourme Iwona Bartkowiak‐Broda Katarzyna Niemirowicz‐Szczytt 《Plant Breeding》2015,134(5):557-563
The PPR‐B gene is responsible for male‐fertility restoration of the Ogura‐type male‐sterile radish plants, and it is located in the complex Rfo locus in the vicinity of similar PPR‐A gene and PPR‐C pseudogene. The aim of this study was to identify PPR‐B alleles and understand the structure of the Rfo locus in radish breeding lines. Five lines of radish with normal male‐fertile cytoplasm were tested. The entire PPR‐B gene was amplified, sequenced and allelic PPR‐B sequences were identified. The results indicated that the maintainer lines 7, 15 and 21 contained a non‐restoring form of PPR‐B protein. A unique PPR‐B was found in lines 24/15 and 31 that are restorer and maintainer lines, respectively. The substitutions might be responsible for the loss of a restoring function of the PPR‐B‐31 allele. Amplification of the PPR‐A/PPR‐B and PPR‐B/PPR‐C intergenic regions allowed to identify rearrangements within Rfo locus. Obtained results confirm the wide allelic variation within the Rfo locus, as well as high genetic complexity of the fertility restoration mechanism in radish. 相似文献
89.
Julia Cartelle Anna Pedr Roxana Savin Gustavo A. Slafer 《European Journal of Agronomy》2006,25(4):365-371
Average grain weight is a major yield component contributing to its variation, especially in Mediterranean regions where grain weight is frequently exposed to terminal stresses affecting grain growth. Most of the literature agrees that wheat grain growth is hardly limited by the source. However, no source–sink ratios studies seem to have been conducted in the Mediterranean region to determine to what degree wheat grain growth is actually limited by the source in these particular regions. We conducted two field experiments in Catalonia (north-eastern Spain), where an old cultivar (Anza) and a more recently released one (Soissons) were sown in a range of different nitrogen and water availabilities and sowing dates. This was to analyse the degree of source limitation for grain growth. Sink size was modified by removing half of the spikelets c. 10 days after anthesis, virtually doubling the availability of assimilates per grain effectively growing.
Trimming the spikes did not produce significant changes in grain growth rate or duration of grain filling. Consequently, grain weight did not respond noticeably to the reduction in sink demand and any eventual response has been far from representing a strong competition among grains during grain filling. 相似文献
90.
Book reviewed in this articles: Cereal Grain Protein Improvement. Shivanna, K. R., and B. M. Johri, The Angiosperm Pollen. Structure and Function. Gustafson, J. P., Gene Manipulation in Plant Improvement. Backer, A. W., Manual of Quantitative Genetics. Fishbeck, G., W. Plarre und W. Schuster (Hrag.) , Hoffmann , W., A. Plarre : Lehrbush der Züchtung landwirtschaftlicher Kulturflanzen, Bd. 2, Spezieller Teil, 2. Auflage. Dodds, J. H. (editor and author), Plant Genetic Engineering. Fiechter, A. (managing editor), Advanced in Biochemical Engineering/Biotechnology. Vol. 31. Plant Cell Culture. 相似文献