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41.
Hilde Nybom Artur Mikiciński Larisa Garkava-Gustavsson Jasna Sehic Mariusz Lewandowski Piotr Sobiczewski 《Trees - Structure and Function》2012,26(1):199-213
Fire blight (Erwinia amylovora) causes serious damage to pome fruit orchards, and identification of germplasm with heritable disease resistance is therefore
crucial. Two dominant SCAR (sequence characterised amplified region) marker alleles (AE10-375 and GE-8019), flanking a previously
identified QTL (quantitative trait locus) for resistance to fire blight on ‘Fiesta’ linkage group 7 in apple cultivars related
to ‘Cox’s Orange Pippin’, were screened on 205 apple cultivars. Both marker alleles were present in 22% of the cultivars,
indicating presence of the QTL allele for tolerance, and both were lacking in 25%, indicating homozygosity for absence of
the QTL tolerance allele. However, 33% had only the marker allele AE10-375, while 20% had only GE-8019, suggesting that some
cultivars with the dominant alleles for both of the flanking markers can carry these on separate chromosomes and may lack
the QTL allele for tolerance. In 2009 and 2010, terminal shoots of greenhouse-grown grafted trees of 21 cultivars (only 20
in 2010) were inoculated with Erwinia amylovora. ‘Idared’ (susceptible) and ‘Enterprise’ (tolerant) were included as controls. Disease severity for each cultivar was expressed
as percentage of necrosis in relation to entire length of shoot, and the ranking of cultivars in 2009 and 2010 was compared
with a Spearman rank correlation test, P < 0.01. A relationship between presence of both flanking marker alleles for tolerance and level of fire blight tolerance
was confirmed with a Mann–Whitney U-test, P < 0.01 in 2009, and P < 0.05 in 2010. A PCO (principal coordinate) analysis based on band profiles obtained with 12 SSR (simple sequence repeat)
loci produced three loose clusters, two of which contained known offspring of ‘Cox’s Orange Pippin’, and one with cultivars
that were either unrelated or had an unknown origin. Cases where DNA markers did not predict level of fire blight damage as
expected, were, however, as common among descendants of ‘Cox’s Orange Pippin’ as among apparently unrelated cultivars. Obviously
the ‘Fiesta’ LG 7 QTL has some predictive value, both for known ‘Cox’ relatives and others, but more efficient markers would
be desirable for marker-assisted selection. 相似文献
42.
Kałużna Monika Albuquerque Pedro Tavares Fernando Sobiczewski Piotr Puławska Joanna 《Applied microbiology and biotechnology》2017,101(2):903-903
Applied Microbiology and Biotechnology - 相似文献
43.
The intermolecular interaction energies in central guanine triad of telomeric B-DNA were estimated based on ab initio quantum
chemistry calculations on the MP2/aDZ level of theory. The source of structural information was molecular dynamics simulation
of both canonical (AGGGTT) and oxidized (AG8oxoGGTT) telomere units. Our calculations demonstrate that significant stiffness
of central triad occurs if 8oxoG is present. The origin of such feature is mainly due to the increase of stacking interactions
of 8oxoG with neighbouring guanine molecules and stronger hydrogen bonding formation of 8oxoG with cytosine if compared with
canonical guanine. Another interesting observation is the context independence of stacking interactions of 8oxoG. Unlike to
5′-G2/G3-3′ and 5′-G3/G4-3′ sequences which are energetically different, 5′-G2/8oxoG3-3′ and 5′-8oxoG3/G4-3′ sequences are almost iso-energetic. 相似文献
44.
Golankiewicz B Januszczyk P Zeidler J Popenda M 《Nucleosides, nucleotides & nucleic acids》2004,23(1-2):127-136
Two new types of imidazole derivatives: N-(2-R1-5-R2-1H-imidazol-4-yl) thioureas 7a-g and N-(2-R1-5-R2-1H-imidazol-4-yl) formamides 8b,c,g were obtained in high yields by the hydrolytic degradation of 6-R1-8-R2-2-thioxo-2,3-dihydroimidazo[1,5-a]-1,3,5-triazin-4(1H)-ones 5a-g and 6-R1-8-R2-imidazo[1,5-a]-1,3,5-triazin-4(3H)-ones 6b,c,d, respectively. The tautomeric preferences of the new imidazoles were determined. 相似文献
45.
Guangxi Wu He Zhao Chenhao Li Menaka Priyadarsani Rajapakse Wing Cheong Wong Jun Xu Charles W. Saunders Nancy L. Reeder Raymond A. Reilman Annika Scheynius Sheng Sun Blake Robert Billmyre Wenjun Li Anna Floyd Averette Piotr Mieczkowski Joseph Heitman Bart Theelen Markus S. Schr?der Paola Florez De Sessions Geraldine Butler Sebastian Maurer-Stroh Teun Boekhout Niranjan Nagarajan Thomas L. Dawson Jr. 《PLoS genetics》2015,11(11)
Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin’s carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin. 相似文献
46.
Synchrony in the phenology of a culturally iconic spring flower 总被引:1,自引:0,他引:1
Sparks TH Mizera T Wójtowicz W Tryjanowski P 《International journal of biometeorology》2012,56(2):407-409
We examine the flowering phenology of the cultural iconic Spring Snowflake Leucojum vernum, a considerable tourist attraction, recorded from two sites in western Poland. Flowering dates at the two sites were closely
correlated but about 6 days later at the more natural area. The end of flowering was associated with the start of canopy leafing.
Early flowering was related to a longer flowering season which may benefit ecotourism under future climate warming. 相似文献
47.
Nowacki A Smiataczowa K Kasprzykowska R Dmochowska B Wiśniewski A 《Carbohydrate research》2002,337(3):265-272
Four isomers of methyl 2-deoxy-D-arabino-hexosides were isolated by HPLC as chromatographically homogeneous compounds. The rates of pyranoside isomerization (alpha(p) and beta(p)) at 40 degrees C and of furanoside isomerization (alpha(f) and beta(f)) at 26 degrees C were determined. A mechanism has been suggested for transformations taking place during isomerization of methyl 2-deoxy-D-arabino-hexosides in methanolic solution catalyzed with hydrogen chloride. 相似文献
48.
49.
The hooded crow Corvus cornix is a west Palaearctic, solitary nesting, monogamous corvid. In the breeding season, populations are characterized by a social organization wherein breeding pairs are territorial and non-breeding individuals, called floaters, live in flocks. During a study of the breeding ecology of the hooded crow, conducted in a protected flooded area, we monitored nests with video cameras. We recorded two separate incidents when intruders attacked a female at the nest. We believe that she remained in the nest in order to prevent the strangers cannibalizing the nestlings by mantling over the brood. The spatio-temporal occurrence of these attacks suggests that the observed behaviour is intraspecific sexual aggression wherein non-breeding males mounted an immobilized female. 相似文献
50.