bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Two Commercial Vaccines to Campylobacter fetus subspecies on Heifers Naturally Challenged
Authors: Cobo E. R. , Cipolla A. , Morsella C. , Cano D. , Campero C. 
Published: March 2003

SummaryEfficacy of two commercial vaccines containing Campylobacter fetus subspecies on heifers naturally challenged by service with an infected bull was tested. Sixteen heifers were vaccinated parentally two times with 3 weeks as interval, eight with commercial vaccine A and the other eight with commercial vaccine B. Eight other heifers were used as unvaccinated controls. Forty days after the first vaccine dose, the heifers were served by an infected bull during 60 days. Measure of systemic immune response and identification of the microorganism from genital secretions by culture and immunofluorescent antibody test (IFAT) were done. Vaccinated and control heifers had a poor reproductive performance (pregnancy rates were 2/8, 3/8 and 0/8 in groups A, B and C, respectively) and were infected by both methods during breeding time and after it. Moreover, one heifer in the groups B and C remained infected until 300 days post‐breeding time. Neither vaccinated nor control heifers had an important increment of systemic antibody level. Only, they had a slight increment of antibody level after the breeding period and it may be because of natural stimulus by the infected bull during the copula. Culture and IFAT yielded high correlation on identification of C. fetus subspecies.
Immune Response to Japanese Rabies Vaccine in Domestic Dogs
Authors: Shimazaki Y. , Inoue S. , Takahashi C. , Gamoh K. , Etoh M. , Kamiyama T. , Makie H. 
Published: March 2003

SummaryTo evaluate the immune response induced by Japanese rabies vaccine for veterinary use as international units (IU), we measured levels of rabies antibody in serum samples from dogs by the rapid fluorescent focus inhibition test (RFFIT). In dogs immunized with a reference vaccine (potency level of 3.1 IU/ml), prepared by the same method as that used to produce commercial vaccine, and its dilutions (1 : 2 or 1 : 4), neutralizing‐antibody levels increased to 1.0–2.0 IU/ml over a period of 1 month and then decreased to 0.2–1.5 IU/ml over a period of 1 year after the first vaccination and showed a remarkable increase to 12–47 IU/ml after the second vaccination. Sixty‐five (74.7%) of the 87 serum samples from domestic dogs that were tested were seropositive (≥0.1 IU/ml). However, the seropositive rate in dogs less than 1‐year old at the time of vaccination was low (57.1%), and the antibody levels in these dogs were not sufficiently high for the rabies antibody titre in serum to be maintained for 1‐year. Levels of rabies antibody in all serum samples were also measured by the virus neutralizing test (VNT), and a strong correlation (r > 0.95) was found between the results of the RFFIT and those of the VNT.
Temporal Variations of Nutrients, ­Chlorophyll a and Particulate Matter in Three Coastal Lagoons of Amvrakikos Gulf (Ionian Sea, Greece)
Authors: Kormas Konstantinos A. , Nicolaidou Artemis , Reizopoulou Sofia 
Published: March 2003

Abstract. The temporal variations of nutrients, chlorophyll a (chl a), suspended particulate matter (SPM) and particulate organic carbon (POC) were measured over 12 months in three shallow coastal brackish water lagoons of the Amvrakikos Gulf, Ionian Sea. Two of the lagoons, Tsoukalio and Rodia, are interconnected but separated from Logarou by a narrow strip of land. Logarou has a better water exchange with the sea as indicated by the higher salinity and dissolved oxygen concentrations and the smaller variation of the above‐mentioned parameters. Nitrate concentrations were largely the same in the three lagoons and higher than in the Amvrakikos Gulf. Phosphate concentrations in Logarou exceeded by far those of Tsoukalio/Rodia; the increased phosphate levels recorded in January caused an extended phytoplankton bloom with chl a concentrations higher than in the other two lagoons. Chl a in Tsoukalio was positively correlated with nitrate whereas in the most shallow lagoon, Logarou, it showed a positive correlation with light winds (force 4 and lower), probably caused by resuspension from the sediment. Increased phytoplankton biomass in Logarou coupled with the better water exchange may be related to the higher fish production in this lagoon.
Anti‐Cryptococcus activity of combination of extracts of Cassia alata and Ocimum sanctum
Authors: Ranganathan S. , Balajee S. A. M. 
Published: March 2003

SummaryThe paper reports the anti‐Cryptococcus activity of combination of ethanolic extracts of leaves of Cassia alata and Ocimum sanctum. The activity of combination of the extracts was heat‐stable and worked at acidic pH.
Heritability of resistance to foliar late blight in a diploid hybrid potato population of Solanum phureja×Solanum stenotomum
Authors: Haynes K. G. , Christ B. J. 
Published: March 2003

AbstractThe emergence of new races of Phytophthora infestans has necessitated the search for additional sources of potato germplasm with resistance to late blight. This study examined 281 clones, derived from 72 families of a diploid random‐mated hybrid population of Solanum phureja×Solanum stenotomum. The clones were evaluated in a replicated field trial for 2 years with the control cultivar ‘Atlantic’ in Pennsylvania, USA. The P. infestans US‐8 A2 mating type culture was used to inoculate spreader rows of susceptible S. tuberosum cv.‘Russet Burbank’. Percent defoliation caused by the late blight fungus was estimated visually in each plot three times near the end of the growing season. Area under the disease progress curve (AUDPC) was estimated and showed that late blight was more severe in 1997 than in 1996. Genetic differences among clones and significant, but small, clone–environment interaction were detected for AUDPC. Broad‐sense and narrow‐sense heritability estimates, over years, were 0.79 ± 0.05 (P = 0.05) and 0.78 ± 0.29, respectively. Seventy‐five percent of the diploid clones had a significantly lower mean AUDPC than Atlantic. These results support the idea that this diploid population is worthy of use in breeding for late blight resistance in tetraploid potato cultivars.
Developing tomato breeding lines resistant to tomato yellow leaf curl virus
Authors: Pico B. , Ferriol M. , Diez M. J. , Nuez F. 
Published: March 2003

AbstractUsing controlled whitefly‐mediated inoculation techniques, seven Lycopersicon chilense accessions, highly resistant to isolates of tomato yellow leaf curl virus(TYLCV) from Southern Europe, TYLCV‐Sr, were selected. All exhibited similar levels of partial resistance, being symptomless and with low levels of viral DNA accumulation. However, a differential response to infection was found in interspecific hybrids with tomato and inbred lines derived from different L. chilense accessions, allowing a precise discrimination among them. This selection procedure which considers the expression of the resistance genes in the tomato genetic background led to the selection of two highly resistant F1 hybrids derived from L. chilense LA 1932 and LA 1938. A backcrossing programme was initiated, selecting for horticultural characteristics and TYLCV resistance, in field and controlled inoculation conditions. As a result of this programme, six advanced breeding lines (UPV Ty 1, 3, 6, 9, 17 and 53), exhibiting a high level of resistance to TYLCV‐Sr, were obtained. Under high inoculum pressure conditions these lines suffered only 30‐40% yield loss relative to non‐infected control plants, and compared with 90‐95% yield loss in susceptible controls. These lines also have horticultural characteristics appropriate for the fresh market tomato cultivation system in this area, and are a good base material for obtaining commercial hybrids highly resistant to different isolates of TYLCV.
Comparison of QTLs for seed germination under non‐stress, cold stress and salt stress in tomato
Authors: Foolad M. R. , Lin G. Y. , Chen F. Q. 
Published: March 2003

AbstractThe purpose of this study was to examine whether rate of tomato seed germination under non‐stress, cold‐stress and salt‐stress conditions was under similar genetic control by identifying and comparing quantitative trait loci (QTLs) which affect germination rate under these conditions. A fast‐germinating accession (LA722) of the wild tomato species Lycopersicon pimpinellifolium Jusl. and a slow‐germinating cultivar (NC84173, maternal and recurrent parent) of tomato (Lycopersicon esculentum Mill.) were hybridized and BC1 and BC1S1 progeny produced. The BC1 population was used to construct a linkage map with 151 restriction fragment length polymorphism (RFLP) markers. The BC1S1 population (consisting of 119 BC1S1 families) was evaluated for germination under non‐stress (control), cold‐stress and salt‐stress conditions and the mean time to 50% germination (T50) in each treatment was determined. Germination analyses indicated the presence of significant (P < 0.01) phenotypic correlations between T50 under control and cold stress (r = 0.71), control and salt stress (r = 0.58) and cold stress and salt stress (r = 0.67). The QTL analysis indicated the presence of genetic relationships between germination under these three conditions: a few QTLs were identified which commonly affected germination under both stress‐ (cold‐, salt‐ or both) and non‐stress conditions, and thus were called stress‐nonspecific QTLs. A few QTLs were also identified which affected germination only under cold or salt stress and thus were called stress‐specific QTLs. However, the stress‐nonspecific QTLs generally exhibited larger individual effects and together accounted for a greater portion of the total phenotypic variation under each condition than the stress‐specific QTLs. Whether the effects of stress‐nonspecific QTLs were due to pleiotropic effects of the same genes, physical linkage of different genes, or a combination of both could not be determined in this study. The results, however, indicate that the rate of tomato seed germination under different stress and nonstress conditions is partly under the same genetic control.
Genetic relationships in cultivars of hop, Humulus lupulus L., determined by RAPD analysis
Authors: Š Uštar‐Vozlič J. , Javornik B. 
Published: March 2003

AbstractRandom amplified polymorphic DNA (RAPD) was used to evaluate the genetic variability and relationship of 65 hop cultivars from all the major hop‐growing regions in the world. Twenty‐eight selected random primers used in the RAPD reaction generated an average of 38.6%) polymorphic fragments, which was sufficient to produce 47 different RAPD profiles among the cultivars examined. The level of genetic variability was much higher than previously reported. Genetic similarity was estimated and UPGMA cluster analysis was performed using the RAPD data. Cluster analysis separated the cultivars into genetically related RAPD groups which were compared with pedigree data and grouping of the hop cultivars by essential oil type. The RAPD groups, strongly supported by pedigree data, gave more precise information on the level and distribution of genetic variability within hop cultivars than characterization by essential oils. Cultivars were divided into American and European groups, supporting the distinction between two geo‐graphically distinct hop germplasms. Five genetically distinct groups revealed differences within the European germplasm, reflecting past hop breeding practices which have been adopted in different regions. The use of RAPD markers for hop germplasm characterization and genetic diversity study is discussed.
Molecular marker‐facilitated pyramiding of different genes for powdery mildew resistance in wheat
Authors: Liu J. , Liu D. , Tao W. , Li W. , Wang S. , Chen P. , Cheng S. , Gao D. 
Published: March 2003

AbstractBreeding durable resistance to pathogens and pests is a major task for modern plant breeders and pyramiding different resistance genes into a genotype is one way of achieving this. Three powdery mildew resistance gene combinations, Pm2+Pm4a, Pm2+Pm21, Pm4a+Pm21 were successfully integrated into an elite wheat cultivar ‘Yang047′. Double homozygotes were selected from a small F2 population with the help of molecular markers. As the parents were near‐isogenic lines (NILs) of ‘Yang158′, the progenies showed good uniformity in morphological and other non‐resistance agronomic traits. The present work illustrates the bright prospects for the utilization of molecular markers in breeding for host resistance.
A maternal factor conferring resistance to crown rust in Lolium multiflorum cv.‘Axis’
Authors: Adams E. , Roldan‐Ruiz I. , Depicker A. , Bockstaele E. Van , Loose M. de 
Published: March 2003

AbstractThe genetic basis for crown rust resistance was analysed in the progeny of reciprocal crosses between Lolium multiflorum plants that were either resistant (cv. ‘Axis’) or susceptible to crown rust. The progeny harvested from the resistant parent was two‐ to seven‐fold more resistant than the progeny harvested from the susceptible parent. These data indicate the presence of a maternal factor which increases resistance to crown rust in some of the ryegrass plants used as parents.
Postulation of leaf‐rust resistance genes in Czech and Slovak barley cultivars and breeding lines
Authors: Dreiseitl A. , Steffenson B. J. 
Published: March 2003

AbstractLeaf‐rust resistance (Rph) genes in 61 Czech and Slovak barley cultivars and 32 breeding lines from registration trials of the Czech Republic were postulated based on their reaction to 12 isolates of Puccinia hordei with different combinations of virulence genes. Five known Rph genes (Rph2, Rph3, Rph4, Rph7, and Rph12) and one unknown Rph gene were postulated to be present in this germplasm. To corroborate this result, the pedigree of the barley accessions was analysed. Gene Rph2, as well as Rph4, originated from old European cultivars. The donor of Rph3, which has been mainly used by Czech and Slovak breeders, is ‘Ribari’ (‘Baladi 16’). Rph12 originates from barley cultivars developed in the former East Germany. Rph7 in the registered cultivar ‘Heris’ originates from ‘Forrajera’. A combination of two genes was found in 10 cultivars. Nine heterogeneous cultivars were identified; they were composed of one component with an identified Rph gene and a second component without any resistance gene. No gene for leaf rust resistance was found in 17 of the accessions tested. This study demonstrates the utility of using selected pathotypes of P. hordei for postulating Rph genes in barley.
Genetic analysis of β‐amylase thermostability to develop a DNA marker for malt fermentability improvement in barley, Hordeum vulgare
Authors: Kaneko T. , Kihara M. , Ito K. 
Published: March 2003

Abstractβ‐Amylase thermostability is one of the major factors affecting fermentability in the brewing process; consequently, it could be used as a selection marker for the trait. In order to clarify what controls its thermostability, the linkage analysis of β‐amylase thermostability and its genotype as restriction fragment length polymorphism patterns was performed in three cross populations. Then, β‐amylase cDNAs cloned from the three varieties which had a different thermostability type were expressed in Escherichia coli. According to the results of the linkage analysis and gene expression test, it was concluded that β‐amylase thermostability resulted from a difference in its structural gene. Furthermore, to construct an STS marker for the gene, the gDNA sequences of β‐amylase were compared among the three varieties, which had different thermostabilities. Although there were many differences in the intron sequence, few nucleotides differed in the exon region. Based on the variation in the intron region, a sequence‐tagged‐site marker was constructed to detect β‐amylase genotypes in breeding material.
Molecular mapping of the leaf rust resistance gene Rph7 in barley
Authors: Graner A. , Streng S. , Drescher A. , Jin Y. , Borovkova I. , Steffenson B. J. 
Published: March 2003

AbstractLeaf rust of barley, caused by Puccinia hordei Otth, is an important foliar disease in most temperate regions of the world. Sixteen major leaf rust resistance (Rph) genes have been described from barley, but only a few have been mapped. The leaf rust resistance gene Rph7 was first described from the cultivar ‘Cebada Capa’ and has proven effective in Europe. Previously mapped restriction fragment length polymorphism (RFLP) markers have been used to determine the precise location of this gene in the barley genome. From the genetic analysis of a ‘Bow‐man’/‘Cebada Capa’ cross, Rph7 was mapped to the end of chromosome 3HS, 1.3 recombination units distal to the RFLP marker cMWG691. A codominant cleaved amplified polymorphic site (CAPS) marker was developed by exploiting allele‐specific sequence information of the cMWG691 site and adjacent fragments of genomic DNA. Based on the large amount of polymorphism present in this region, the CAPS marker may be useful for the marker‐assisted selection of Rph7 in most diverse genetic backgrounds.
Combination of resistance tests and molecular tests to postulate the yellow rust resistance gene Yr17 in bread wheat lines
Authors: Robert O. , Dedryver F. , Leconte M. , Rolland B. , de Vallavieille‐Pope C. 
Published: March 2003

AbstractYellow rust caused by Puccinia striiformis is a wheat disease of worldwide importance. The Yr17 resistance gene introgressed from Aegilops ventricosa was effective, in France, against all yellow rust isolates until 1998. The SC‐Y15 marker is one of three molecular markers closely linked to Yr17. In this paper, results obtained are compared with the molecular marker SC‐Y15 and with resistance tests performed at the seedling and adult plant stages on 31 lines from five populations derived from recurrent selection programmes. The resistance tests showed that Yr17 controlled the resistance in seven lines, but that others had additional resistance at the adult stage (18 lines). The molecular test corresponded well with the resistance test in most lines (98% of 156 plants tested), including individual plants that were resistant or susceptible in heterogeneous lines. It also indicated the presence of Yr17 in lines in which it could not be identified by the resistance test because of the presence of other genes. Three of the 156 plants tested appeared to have the gene Yr17 according to the resistance tests, but lacked the molecular marker. These could have resulted from breakage of the linkage, the number being consistent with the estimate of linkage already published. This indicated the need for a resistance test, at least in later stages of breeding programmes, if it is considered essential to have the Yr17 gene present. The use of the selected lines in breeding programmes is also discussed.
Large‐scale production of wheat and triticale double haploids through the use of a single‐anther culture method
Authors: Tuvesson S. , Ljungberg A. , Johansson N. , Karlsson K.E. , Suijs L. W. , Josset J.P. 
Published: March 2003

AbstractA total of 257 parental wheat and 38 triticale lines were used for anther culture. On average, 2.1 green wheat haploids were obtained per spike. This response occurred irrespective of the origin of the material (Germany, France, Sweden or UK) and 5 years of testing. Triticale responded with 5.3 green haploids per spike. Using the criterion that one parental line should give at least one green haploid per spike in the screening experiment, green haploids were produced from 88 out of 91 F1 wheat breeding combinations and from each of 21 F1 and F2 triticale breeding combinations. An average of 4.7 green plants were obtained per spike from the wheat production programme, while the triticale programme gave an average of 6.2 green plants per spike. A single medium supplemented with different hormones for anthers and embryos was used for culture of both crops.
Genotypic variation for tolerance to phosphorus deficiency in rice and the potential for its exploitation in rice improvement
Authors: Wissuwa M. , Ae N. 
Published: March 2003

AbstractDeficiency in phosphorus (P) can severely limit rice yields. Developing cultivars with tolerance to P deficiency may represent a more sustainable solution than sole reliance on fertilizer application. To assess genotypic variation for tolerance to P deficiency the P uptake of 30 genotypes was measured on P‐deficient soil. Variation for P uptake was high, ranging from 0.6 to 12.9 mg P/plant. Traditional varieties were superior to modern varieties. A major quantitative trait locus for P uptake had previously been identified in a population developed by crossing the modern variety ‘Nipponbare’ with the P deficiency‐tolerant landrace ‘Kasalath’. This quantitative trait locus was transferred to ‘Nipponbare’ by three backcrosses. Under P deficiency this improved line surpassed ‘Nipponbare’ in P uptake by 170% and in grain yield by 250%. These results show that the genotypic variation for tolerance to P deficiency in rice can be used successfully in rice improvement. By combining high P uptake of the donor variety ‘Kasalath’ with a high harvest‐index characteristic of modern varieties it was possible to more than triple the grain yield of ‘Nipponbare’ under P deficiency.
The Aegilops ventricosa segment on chromosome 2AS of the wheat cultivar ‘VPM1’ carries the cereal cyst nematode resistance gene Cre5
Authors: Jahier J. , Abelard P. , Tanguy M. , Dedryver F. , Rivoal R. , Khatkar S. , Bariana H. S. , Koebner R. 
Published: March 2003

AbstractPrevious studies showed that the intermediate level of resistance in bread wheat line ‘VPM1’ to pathotype Ha12 of the cereal cyst nematode could be conferred by an Aegilops ventricosa‐derived gene, CreX, in chromosome arm 2AS, which also carries the rust resistance genes Yrl7, Lr37 and Sr38. Near isogenic lines (NILs) differing for the presence and absence of the Ae. ventricosa‐derived linked genes Yrl7/Lr37/Sr38 were tested with cereal cyst nematode. Lines carrying Yr17 produced significantly fewer nematode cysts than the controls. An infested soil experiment produced better differentiation among resistant and susceptible genotypes. Susceptibility of ‘Trident’ indicated that linkage between CreX and Yr17 is incomplete. Microsatellite markers did not differentiate between ‘Trident’ and CreX‐carrying genotypes. However, Xgwm636 (104) was associated with the presence of Yr17 in all six genetic backgrounds. Since none of the reported cereal cyst nematode resistance genes is located in chromosome 2AS, CreX was designated as Cre5.
Multi‐trait selection in a diallel crossing scheme of cocoa
Authors: Ndoumbé M. , Bieysse D. , Cilas C. 
Published: March 2003

AbstractCocoa breeding seeks to increase the yield by area unit. In this context, one must consider the resistance to Phytophthora disease, the most serious one in cocoa culture. Thus, herein two traits were used: yield, i.e. number of healthy pods obtained in 7 years and Phytophthora resistance, estimated by pod rot rate. A combined individual‐family selection is proposed on the basis of the total genetic value in order to spread clonal material. This selection method was applied in a 6 × 6 diallel scheme in Cameroon. The heritability of Phytophthora resistance (near 0.2) was higher than for yield (0.13). A selection index was constructed to obtain good genetic gains on each of the two traits (yield and Phytophthora resistance). To improve prediction of genetic values, a third trait, potential yield, was used. With the chosen weight, the expected genetic gain was about 35% for resistance at 1% level of selection. This selection was applied and a confirmation trial is being established with the selected trees.