bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polluting Profiles of Dieldrin and DDTs in Laying Hens of Osaka, Japan
Authors: Furusawa N. , Morita Y. 
Published: March 2003

SummaryContaminating/accumulating levels of organochlorine pesticides in extractable fats from a basal diet, eggs and seven tissues (adipose tissue, blood, kidney, liver, muscle, ovary and oviduct) and excreta of laying hens that were kept in a general poultry farm of Japan were examined. No benzene hexachlorides or aldrin was detected [<1 part per billion (p.p.b.)] overall. Dieldrin and all DDTs (p,p′‐DDE, o,p′‐DDT, p,p′‐DDD and p,p′‐DDT) were contaminated in the dietary fats (mean range 10–70 p.p.b.). Although dieldrin (4–58 p.p.b.), p,p′‐DDE (65–196 p.p.b.) and p,p′‐DDT (30–73 p.p.b.) were found to be accumulated in all the tissue fats and egg yolk fats, they were not detected in the dried excreta. Accumulations of o,p′‐DDT and p,p′‐DDD were found only in the liver fat (92 p.p.b.) and in the kidney fat (27 p.p.b.), respectively. In all the samples, p,p′‐DDE levels were highest in comparison with the other compounds. For all organochlorine pesticides detected, the accumulated levels were well below the practical residue limits.
Frequent Exposure of Mice to Crude Brucella abortus Proteins Down‐regulates Immune Response
Authors: Oñate A. , Andrews E. , Beltran A. , Eller G. , Schurig G. , Folch H. 
Published: March 2003

SummaryMice repeatedly immunized via the intraperitoneal route with a Brucella abortus antigen lost their ability to develop a strong in vitro lymphoproliferative response. This result correlates with a decreased tendency of the lymphoid population to produce interferon‐γ when stimulated in culture with the immunizing antigen. With respect to the humoral response, as the number of immunizations increased, the animals produced more specific immunoglobulin M and immunoglobulin G1 antibodies. It is postulated that the long‐term exposure of an animal to Brucella antigen changes the nature of the immune response from a T‐cell‐mediated response to a humoral response favouring the establishment of the disease.
Natural Distemper in Vaccinated and Unvaccinated Dogs in Warsaw
Authors: Jóžwik A. , Frymus T. 
Published: March 2003

SummaryTwo hundred and twenty‐four dogs with clinical signs of distemper were examined for the presence of canine distemper virus (CDV) in mucous membranes by direct immunofluorescence assay. The study showed that 22% of the animals were CDV‐positive. Most (33/50; 66%) of the infected dogs had never been vaccinated against distemper, whereas only 11 of 50 (22%) CDV‐positive animals were immunized at least once. The difference in the infection rate between vaccinated and unvaccinated animals was statistically significant (P < 0.001), as assessed by the χ2 test. It is concluded that distemper is an important disease among dogs in Warsaw and the vaccination significantly reduces the risk of this disease.
Symbiotic Relations of Sediment‐Agglutinating Nematodes and Bacteria in Detrital Habitats: The Enzyme‐Sharing Concept
Authors: Riemann Franz , Helmke Elisabeth 
Published: March 2003

Abstract. A new concept (‘enzyme sharing’) concerning the interaction of marine nematodes and microbes in the degradation of sedimentary detritus is presented. Elements of this concept are (1) the notorious tendency of many aquatic nematodes to agglutinate detrital particles by mucus secretions, (2) new observations on the stimulation of microbial growth by nematodes in agar plates, and (3) literature data on limited endogenous proteolytic capacities of aquatic nematodes.

Observations on nematode‐microbe associations in agar plates prompted the conceptual synthesis. In agar medium without the addition of any nutrients a spectacular growth of bacteria was visible on the sinusoidal crawling trails of nematodes only 2 – 3 days after introduction of the worms (species of Adoncholaimus, Anoplostoma and Sabatieria). Juveniles of Anoplostoma that hatched in the agar cultures left their minute trails in the medium and these were rapidly occupied by bacteria. The nematodes repeatedly visited their bacterial trails, which persisted as a peculiar biotic structure for more than one year and survived the nematodes. In sterile agar preparations containing the fluorogenic methylumbelliferyl‐β‐glucoside in the presence of the nematode Adoncholaimus, an enhanced fluorescence of the medium was visible, indicating β‐glucosidase activity. We therefore assume that oncholaimid nematodes discharge enzymes that alone, or in concert with microbial activities, contribute to the hydrolytic cleavage of refractory polysaccharides containing β‐glucosidic bonds such as agar components and cellulose. The sugars thus produced may then be taken up by the nematodes and concomitantly support the conspicuous growth of microbes. Since we did not observe any feeding of the nematodes on the associated microbes in agar plates, we question the nutritive potential of intact microbial cells for a number of nematodes abounding in detrital habitats, and call attention to the significance of ambient dissolved or adsorbed organic monomeric nutrients. Consequently, we perceive the puzzling perpetual accretion of detrital organic particles to sediment agglutinations by nematodes as an adaptation for operating an ‘enzymatic reactor’ for the production of dissolved nutrients. We hypothesise a relationship of mutual commensalism of nematodes and heterotrophic microbes in detrital habitats and propose the term ‘enzyme sharing’ for this relationship. Both parties invest in a common enzyme pool that decomposes organic detritus for their nutrition. We present here evidence that nematodes contribute β‐glucosidase, which is involved in the cellulase system. Data from the literature suggest that microbial enzymatic processing of detrital proteins yields amino acids available to nematodes, which apparently have no efficient proteolytic enzyme system in their intestines.
Genotypic variation for drought tolerance in Vicia faba
Authors: Link W. , Abdelmula A. A. , Kittlitz E. Von , Bruns S. , Riemer H. , Stelling D. 
Published: March 2003

AbstractInstability of yield in faba bean is partly caused by drought susceptibility. Four sets with 10‐19 faba bean genotypes each were evaluated in multilocal field trials between 1992 and 1996. Stress occurred as natural drought in one experiment and as artificial terminal drought in three experiments. Artificial drought was induced by rain shelters; the control treatment was irrigated. Tolerance was assessed as the ratio of yield under drought (Yd) to well‐watered yield (Yw). Highly significant variances between genotypes occurred; heritability of tolerance was 0.51 < h2 <0.88. Exotic (North African. Latin American) genotypes were more tolerant than adapted material. Correlations between Yw and Yd were 0.77** < r <0.97**, and variance of Yd was less than one‐third of the variance of Yw. Drought tolerance was negatively correlated with Yd (‐0.41 < r < ‐0.22). Relative reduction of plant height due to drought was a promising trait to improve drought tolerance indirectly in two sets. The prospects of improving Yd are good: heritability was 0.68 < h2 < 0.86. Genetic improvement of drought tolerance also seems feasible. A specific cross was proposed to create improved material.
Molecular and agronomic characterization of wheat‐Agropyron intermedium recombinant chromosomes
Authors: Khan I. A. 
Published: March 2003

AbstractThirty‐six wheat‐Agropyron intermedium (host) Beauv. [Syn. Trichopyrum intermedium (host) A. Love, Elytrigia intermedia (host) Nevski, Thinopyrum intermedium (host) Barkworth and Dewey] 7A/7Ai‐1 recombinant chromosomes were characterized using DNA markers. Analysis of recombinant chromosomes using 15 restriction fragment length polymorphism probes identified the homoeologous crossover products that had varying length of A. intermedium chromatin introgressed onto chromosome 7A of common wheat. The linear order of the probe loci was established along the lengths of the chromosomes. The short arm recombinants that had A. intermedium chromatin distal to the locus Xpsr108 and proximal to the locus Xpsr119 were resistant to wheat stem rust, indicating that the rust resistance gene (Sr44) was located on the distal part of chromosome arm 4Ai‐1s. The barley yellow dwarf virus (BYDV) resistance gene reported to be present on the long arm of chromosome 7Ai‐1 was found to be ineffective against the BYDV serotype used in the present study.
Dicamba and growth condition effects on doubled haploid production in durum wheat crossed with maize
Authors: Knox R. E. , Clarke J. M. , DePauw R. M. 
Published: March 2003

AbstractDoubled haploid plants are useful in genetic studies and plant breeding, but a consistent and satisfactory frequency of production has been difficult to achieve in durum wheat. Triticum turgidum L., using the maize pollen method. The objective of this study was to develop an objective method of producing doubled haploids in durum wheat. Plant growing and handling conditions, aspects of hormone treatments, wheat genotype and pollen source were considered. The number of caryopses, embryos, haploids, doubled plants and doubled plants that set seed were measured. Although growth conditions, pollen source, method of handling plants and wheat genotype are important considerations, the type of hormone was found to be most significant in the production of doubled haploid plants. When 50mg/l dicamba was substituted for 100 mg/l 2,4‐D the number of doubled haploids per spike increased from 0.2 for the best 2,4‐D treatment to 1.3 for the dicamba treatment. This increased frequency was largely attributed to an increase in the number of caryopses generated for each spike emasculated and from an increased frequency of germination of embryos to haploid plantlets. The best production of caryopses was 0.41 caryopses per florest with 2,4‐D. The best production of haploids per 100 florets was 12 with dicamba and 1.65 with 2,4‐D. The frequency of one doubled haploid per emasculated spike through the use of dicamba is a practical level for generating populations for genetic studies.
Heritability of early blight resistance in a Lycopersicon esculentum×Lycopersicon hirsutum cross estimated by correlation between parent and progeny
Authors: Foolad M. R. , Lin G. Y. 
Published: March 2003

AbstractSixteen‐hundred BC1 plants of a cross between an early blight (EB) susceptible tomato (Lycopersicon esculentum Mill.) breeding line (‘NC84173’ maternal and recurrent parent) and a resistant accession (‘PI126445’) of the tomato wild species Lycopersicon hirsutum Humb. and Bonpl. were grown in a field in 1998. This population was segregating (among other traits) for growth habit, self‐incompatibility and earliness in maturity. To eliminate confounding effects of these factors on disease evaluation and h2 estimation, plants that were self‐incompatible, indeterminate and/or late‐maturing were eliminated. The remaining plants (146), which were self‐compatible and determinate (sp./sp.) in growth habit, with early‐ to mid‐season maturity, were evaluated for EB resistance and self‐pollinated to produce BC1S1 seed. The 146 BC1S1 progeny families, consisting of 30 plants per family, were grown in a replicated field trial in 1999 and evaluated for EB resistance and plant maturity. For each of the 146 BC1 plants and corresponding BC1 families, the area under the disease progress curve (AUDPC) and final disease severity (final percentage defoliation) were determined and used to measure disease resistance. The distributions of the AUDPC and final percentage defoliation values in the BC1 and BC1S1 generations indicated that resistance from ‘PI126445’ was quantitative in nature. Estimates of h2 for EB resistance, computed by correlation between BC1S1 progeny family means and BC1 individual plant values, ranged from 0.69 to 0.70, indicating that EB resistance of ‘P1126445’ was heritable. Across BC1S1 families, a small, but significant, negative correlation (r = ‐0.26, P < 0.01) was observed between disease resistance and earliness in maturity. However, several BC1S1 families were identified with considerable EB resistance and reasonably early maturity. These families should be useful for the development of commercially acceptable EB‐resistant tomato lines.
Adaptation and ecological differentiation in wheat with special reference to geographical variation of growth habit and Vrn genotype
Authors: Iwaki K. , Haruna S. , Niwa T. , Kato K. 
Published: March 2003

AbstractGeographical variation of growth habit was studied for 749 landraces from various parts of the world, with special reference to their adaptation and ecogeographical differentiation. The total frequency of spring‐type landraces was 49.9%, and varied between localities. Spring‐type landraces were frequent in two distinct areas where the average January temperature was either below ‐7°C or above 4°C, with winter‐type landraces in areas from ‐7°C to 4°C. These results indicated that geographical variation of growth habit is closely related to the degree of winter coldness. An analysis of the Vrn genotype for 216 spring‐type landraces demonstrated the uneven distribution of four Vrn genes, with Vrn4 being the least frequent. The adaptive Vrn genotype was different between localities. Genotypes carrying Vrn‐A1 and additional Vrn gene(s) were frequent in two distinct areas where the average January temperature was either below ‐7°C or over 10°C, while genotypes with any of three Vrn genes, except Vrn‐A1, adapted to areas with temperatures from 4°C to 10°C. Therefore, it was concluded that the adaptability of wheat landraces differed depending on their growth habit and Vrn genotype, and that ecotypes with different Vrn genotypes were allopatrically distributed as a result of adaptation to different winter temperature. However, the differential distribution of Vrn‐B1, Vrn‐D1 and Vrn4 could not be explained by their adaptability, and might reflect the polyphyletic origin of common wheat.
Multivariate analysis of traits determining adaptation in cultivated barley
Authors: Karsai I. , Mészáros K. , Láng L. , Hayes P. M. , Bedö Z. 
Published: March 2003

AbstractThirty‐nine barley varieties of different origin, representing different growth types, were included in a series of experiments aimed at analysing the variability in vernalization response, photoperiod sensitivity and earliness per se and establishing the types of ecoclimatic adaptability using multivariate analysis. In the case of spring barley varieties there was no correlation between any of the three traits. For winter barleys, a negative correlation was found between photoperiod sensitivity and vernalization response and between photoperiod sensitivity and earliness per se. Vernalization response and earliness per se showed a positive correlation. Among the winter barley varieties large variations were apparent in photoperiod sensitivity, vernalization response and earliness per se, which resulted in a tremendous variation in flowering patterns and frost tolerance. Between the spring barley varieties only wider variations in photoperiod sensitivity were detected. Based on the cluster analysis, the 39 varieties could be separated into seven groups. The spring barley varieties were placed in two groups, and the winter barleys in five groups representing different adaptational types. Among these five groups two represented the two opposing extreme combinations of photoperiod sensitivity and vernalization response. The combination of large photoperiod sensitivity and no vernalization response resulted in better frost tolerance than did the combination of photoperiod insensitivity and large vernalization response.
Genome‐specific markers of tetraploid wheats and their putative diploid progenitor species
Authors: Khlestkina E. K. , Salina E. A. 
Published: March 2003

AbstractThe objective of this study was to isolate genome‐specific markers from the genomes of tetraploid wheats and the putative donor diploid species on the basis of random amplified polymorphic DNA analysis followed by cross‐hybridization. Twenty different Triticum and Aegilops species and accessions were analysed by polymerase chain reaction (PCR) using 30 random primers. The polymorphic PCR fragments were then isolated, labelled and used in cross‐hybridization screenings. The hybridization results established that one marker was specific to the Ae. speltoides S genome, two to the A genome, one to the B genome and five to the G genomes of polyploid species (and to the genomes of the corresponding progenitor species). Four markers were identified that were specific to both the B and G genomes. Analysis of the Triticum and Aegilops species and accessions supported the notion that Ae. speltoides is more closely related to the B and G genomes of polyploid wheat species than were other members of the Sitopsis section. The data also indicated that the B and G genomes had originated from different accessions of Ae. speltoides.
Environmental and genetic determination of protein content and grain yield in durum wheat under Mediterranean conditions
Authors: Rharrabti Y. , Villegas D. , Garcia del Moral L. F. , Aparicio N. , Elhani S. , Royo C. 
Published: March 2003

AbstractThe unpredictability of the Mediterranean climate causes fluctuations in wheat yield and quality, but offers the opportunity for obtaining high‐quality durum wheat in terms of grain protein content. Twenty‐five durum wheat genotypes were grown under irrigated and rainfed conditions at each of two latitudes in Spain during 1998 and 1999. Differences between latitudes in grain protein content and chlorophyll content in the flag leaf were attributable to nitrogen fertilization management. Cycle length until anthesis was less affected by the environment than grain‐filling duration, and was longer under irrigated conditions than in the rainfed sites. A negative asymptotic curve was the best equation to fit the relationship between yield and protein content, suggesting that yield improvements in fertile environments may be attained with negligible reductions in protein content. ‘Jabato’, ‘Waha’, ‘Lagost‐3’, ‘Massara‐1’ and ‘Vitŕon’ showed medium to high yield, yield stability and high protein content. Chlorophyll content in the flag leaf, measured at anthesis with the soil‐plant analysis development (SPAD) portable field unit, may be useful for the fast and cheap detection of durum wheat genotypes with high grain protein content in drought‐stressed Mediterranean environments.
Morphological traits and high resolution RAPD markers for the identification of the main strawberry varieties cultivated in Argentina
Authors: García M. G. , Ontivero M. , Diaz Ricci J. C. , Castagnaro A. 
Published: March 2003

AbstractEight genotypes of the main Fragaria×ananassa cultivars grown in Argentina were analysed using the random amplified polymorphic DNA (RAPD) technique combined with electrophoresis in polyacrylamide gels. The high resolution of this procedure allowed the detection, with only 13 random primers, of 37 genotype‐specific bands that can be used as markers for verifying the identity of cultivars. By using this approach, three different accessions of the cultivar ‘Pájaro’ exhibited differences in amplification profiles, confirming the need for DNA analysis to prevent misidentification of cultivars. In addition, RAPD bands and morphological traits were used to assess genetic relatedness among cultivars. Comparison of both dendrograms revealed that there is no correlation between the clustering obtained with molecular and morphological characters.
Isolation and linkage mapping of disease‐resistance‐like sequences from various rice cultivars, containing different recognition specificities
Authors: Wang S. , Xiao X. 
Published: March 2003

AbstractDegenerated oligonucleotide primers identified from the nucleotide‐binding sites of known disease resistance (R) genes were used from rice cultivars harbouring different recognition specificities to amplify and clone homologous sequences of R genes. A total of 68 non‐redundant clones, which showed various degrees of sequence homology to R genes, were obtained from 18 rice cultivars. These clones had a high degree of sequence diversity both in the nucleotides and in the predicted amino acids, and were classified into five groups using clustal analysis. Fifteen of the 68 clones were mapped to 17 loci on chromosomes 3, 5, 11 and 12 in the rice molecular linkage map. The loci of the mapped clones correlated with the locations of known rice R genes for blast resistance and bacterial blight resistance on chromosomes 11 and 12. Other mapped loci occurred in cluster on chromosome 3, and correlated with the position of a quantitative trait locus for bacterial blight resistance. The mapping of the R gene homologues may aid the identification and isolation of R gene candidates.
Inheritance of resistance to sunflower downy mildew races 1, 2 and 3 in cultivated sunflower
Authors: Rahim M. , Jan C. C. , Gulya T. J. 
Published: March 2003

AbstractSunflower downy mildew (SDM) caused by Plasmopara halstedii, is a major disease of sunflower. Eleven resistance genes have been identified, but allelic relationships among these genes are not clear. This study examined the inheritance and allelic relationships of genes conferring resistance to SDM races 1, 2 and 3 (virulence phenotypes 100, 300 and 700, respectively) and confirmed a twelfth resistance gene. Three USDA Plant Introductions, AMES 3235, PI 497250, and PI 497938, and three released lines, RHA 266, RHA 274 and DM‐2 were studied. RHA 266 has only the Pl1 gene for race 1 resistance. Digenic inheritance of resistance was found in AMES 3235, PI 497250, and RHA 274. These lines have the Pl1 and Pl12 genes, conferring resistance to race 1, and the Pl2 and Pl11 genes, conferring resistance to race 2. DM‐2 and PI 497938 have Pl12 (but not Pl1 for resistance to race 1, the Pl12 gene (but not the Pl2) for resistance to race 2, and Pl5 for resistance to race 3. These resistance genes will serve as a foundation for future gene designations and genetic diversity studies of resistance to SDM.
Molecular mapping of major genes and quantitative trait loci determining flowering time in response to photoperiod in barley
Authors: Börner A. , Buck‐Sorlin G. H. , Hayes P. M. , Malyshev S. , Korzun V. 
Published: March 2003

AbstractTwo major genes (eam8 and eam10) and two quantitative trait loci (QTL) determining flowering time in barley were associated with restriction fragment length polymorphism markers. The loci eam8 and eam10 were found to map in regions of chromosomes 1HL and 3HL, respectively, already estimated from previous classical linkage analyses. While investigating doubled haploid lines of a spring habit barley mapping population, two QTL for flowering time were detected on chromosomes 1HL and 7HS, respectively, when the material was grown under long photoperiod conditions. When growing the same lines under short photoperiod, no QTL were discernible. Allelic and homoeologous relationships with flowering time loci described earlier in barley and other Triticeae species are discussed.