bluuebunny/crossref_metadata_2025_split huggingface dataset:
Consequences of classical and biotechnological resistance breeding for food toxicology and allergenicity
Authors: Franck‐Oberaspach S. L. , Keller B. 
Published: April 2006

AbstractThe first food products derived from transgenic plants that are resistant to diseases, insects or viruses are now reaching the market and there is growing public concern about problems of allergenicity and toxicological changes in such transgenic food plants. We review the modifications being carried out or envisaged in molecular resistance breeding and specifically consider the allergenic and toxicological potential of the gene products used. Several protein families that contribute to the defence mechanisms of food plants have members which are allergens or putative allergens and some of these proteins are used in molecular approaches to increase resistance. These include α‐amylase and trypsin inhibitors, lectins and pathogenesis‐related proteins. An assessment procedure to avoid the transfer of such allergens is described. The source of the transgene is of great importance for the application of immunological assays. In addition to putative changes in the allergenic potential, the toxicological implications of classical and molecular resistance breeding are discussed. Several ‘self defence’ substances made by plants are highly toxic for mammals, including humans. Examples of molecular approaches that could be of toxicological concern are given. The source of the transgene is of no relevance in assessing the toxicological aspects of foods from transgenic plants. Food safety can also be severely influenced by invading pathogens and their metabolic products. This may result in a trade‐off situation between ‘nature's pesticides’ produced by transgenic plants or varieties from traditional breeding programmes, synthetic pesticides and mycotoxins or other poisonous products of pests.
Glucosinolate content in interspecific crosses of Brassica carinata with B. juncea and B. napus
Authors: Getinet A. , Rakow G. , Raney J. P. , Downey R. K. 
Published: April 2006

Abstract Brassica carinata A. Braun is a highly productive oilseed crop in the Ethiopian highlands, but the seed has a high 2‐propenyl glucosinolate content, which is undesirable. The objective of this study was to introgress, through interspecific crosses, genes for low 2‐propenyl glucosinolate content from the B genome of B. juncea and C genome of B. napus into the B. carinata B and C genomes and thus develop low glucosinolate B. carinata. The cross [(B. carinata×B. juncea) ×B. carinata] yielded plants that contained only ∼ 20 μmoles of 2‐propenyl glucosinolate, which was an 85% reduction compared with levels in B. carinata seed. Plants of the [(B. carinata×B. napus) ×B. carinata] cross had normal high concentrations of 2‐propenyl glucosinolate. Backcross plants of both interspecific crosses also contained 3‐butenyl and 2‐hydroxy‐3‐butenyl glucosinolates. The results of these crosses suggested that genes for glucosinolate synthesis were located on B genome chromosomes of B. carinata because B. napus C genome introgressions did not result in reductions of total glucosinolate contents. The total alkenyl glucosinolate content of one F3 family of the B. juncea backcross was similar to that of the B. juncea parent. It was concluded that through further selection in this family, B. carinata plants could be identified that would be basically free of 2‐propenyl glucosinolate, and have a low total alkenyl glucosinolate content.
The control of adult‐plant resistance to yellow rust by the translocated chromosome 5BS‐7BS of bread wheat
Authors: Law C. N. , Worland A. J. 
Published: April 2006

AbstractThe reciprocal translocation 5BL‐7BL and 5BS‐7BS was widespread in West European wheats 30 years ago, and is probably present in many of their descendants today. In varieties with a history of durable adult‐plant resistance to yellow rust and carrying this translocation, removal of the 5BS‐7BS chromosome gave adult plants which were much more susceptible. It was suggested that this chromosome might therefore carry the gene(s) responsible for a major part of their resistance and possibly their durability. To test this, a series of lines was developed in which 5BS‐7BS chromosomes from both resistant and susceptible varieties were substituted into a number of the durably resistant varieties. In every case, the substituted 5BS‐7BS chromosome, irrespective of origin, was found to produce the resistant phenotype, indicating that background chromosomes were responsible for the differences between the varieties. The resistance and durability of the resistant varieties cannot therefore be due solely to the translocated chromosome. In similar experiments, the 5BS and 7BS arms from varieties not carrying the translocation were substituted into a variety carrying the translocation. In each instance, the lines with the substituted arms were much more susceptible than their recipient, confirming the major effect of the 5BS‐7BS chromosome on resistance. The complete correlation between the translocation and resistance and between increased susceptibility and its absence suggests that the gene(s) for adult‐plant resistance, located on the 5BS‐7BS chromosome, may be closely linked to the break point. Alternatively, it may be a consequence of the close relatedness of some of the varieties. The presence of this gene(s) might be a factor explaining the prevalence of this translocation in some West European wheats.
Sclerotinia rot resistance in red clover: Identification of RAPD markers using bulked segregant analysis
Authors: Page D. , Dulclos B. , Aubert G. , Bonavent J. F. , Mousset‐Déclas C. 
Published: April 2006

AbstractRandom amplified polymorphic DNA (RAPD) was used with the objective of identifying DNA markers linked to the sclerotinia crown and stem rot (SCSR) resistance of red clover. Bulked segregant analysis was used to detect polymorphism that should be linked to SCSR resistance. Two bulks were made by pooling previously extracted DNA. Each bulk (one resistant, and the other susceptible) consisted of eight genotypes from an F2 population obtained from a cross between a susceptible and a resistant parent. A binomial model was used to select RAPD fragments with a low probability of no linkage with SCSR resistance. Four RAPD fragments were retained as candidate markers of SCSR resistance. Three are associated with resistance and one with susceptibility.
Influence of sample size on precision of heritability and expected selection response in red clover
Authors: Xie C. , Mosjidis J. A. 
Published: April 2006

AbstractLimited attention has been given to the effect of sample size on the precision of heritability estimates and expected selection responses. The objectives of this study were to evaluate the effect of sample size on the point estimate, its sampling error and interval width. Monte Carlo simulation and non‐parametric bootstrap were used to estimate parameters in a red clover (Trifolium pratenseL.) data set. We conducted separate analyses for two and four replications, and for combinations of six, 12, 24, 42 and 66 families, each having three, six, nine, 12 and 18 plants. Results showed that the effect of increasing number of families and replications on reduction of sampling error and interval width was greater than that of increasing plants per family. The sampling error and interval width of parameters decreased at a decreasing rate as sample size increased. To reduce the chances of having negative estimates of family variance components and to achieve a narrow confidence interval, an experiment of 42 families, each having six seedlings in four replications would be required.
Successful backcrosses of somatic hybrids betweenSinapis albaandBrassica oleraceawith theBrassica oleraceaparent
Authors: Nothnagel T. , Budahn H. , Straka P. , Schrader O. 
Published: April 2006

AbstractSomatic hybrids betweenSinapis alba(2n= 24) andBrassica oleracea(2n= 18) have been backcrossed with theB. oleraceaparent. Whereas backcrosses with the diploidB. oleraceaparent were unsuccessful, 344 BC1seeds could be obtained from inter‐valence crosses with tetraploidB. oleracea(2n= 4x= 36). The investigated 96 BC1plants segregated for morphological traits and for fertility. They were backcrossed with diploidB. oleraceaor self‐pollinated, depending on their male fertility. The BC1F2and BC2progenies segregated well for the morphological traits. Disturbances were observed especially in the generative phase (flower development and pollen fertility). Both male fertile and male sterile BC1F2and BC2plants were obtained and backcrossed or self‐pollinated with theB. oleraceaparent.The presence of either one of the parental or the cybrid organelle genomes was detected. In the progenies, a stable maternal inheritance of the organelle genome patterns was observed. Isozyme analyses revealed polymorphism for the leucine aminopeptidase (LAP) which was used for the identification ofS. albagenes in the progenies. Cytological investigations showed a clear differentiation between the BC1F2and BC2plants. Whereas the BC1F2plants possess large numbers of chromosomes ranging from 34 to 40, the BC2material was strongly reduced to chromosome numbers ranging from 20 to 22. Preliminary investigation of the meiosis suggests the possibility of introgressions ofS. alba‐DNA into theB. oleraceagenome.
Effect of host allelic dosage on Triticum aestivum–Puccinia recondita specific interaction
Authors: Tranquilli G. E. , Suárez E. Y. , Saione H. , Sacco F. , Tozzini A. 
Published: April 2006

AbstractAllelic dosage changes in host‐pathogen interactions (Triticum aestivum–Puccinia recondita) explain different situations where resistance or susceptibility is observed. Remarkably, the prediction of an interaction change (from compatible to incompatible) by increasing single host allelic dosage is confirmed.Cases of more lasting resistance could also be explained on the basis of these dosage effects. In addition a parallel between specific and nonspecific resistance is established pointing out their basic differences in expression with respect to allelic dosage effects. These situations, together with new possibilities for breeding arising from this knowledge, are discussed.
High‐lysine mutants of rice, Oryza sativa L.
Authors: Kumamaru T. , Sato H. , Satoh H. 
Published: April 2006

AbstractIn order to improve the nutritive value of rice protein, it is necessary to increase the level of lysine and threonine. Ten high‐lysine mutants were selected from N‐methyl‐N‐nitrosourea‐induced (MNU‐induced) mutant lines, using high‐performance liquid chromatography for amino acid analysis. The lysine content of these mutants ranged from 5.10% to 6.38% of total amino acids, while that of the original varieties was about 4%. All high‐lysine mutants also had a greatly increased histidine content and a floury endosperm. An increase in lysine content of the albumin/globulin fraction was characteristic of the MNU‐induced high‐lysine mutants. The segregation ratio of normal to floury endosperm in the F2 seeds from a cross between ‘Kinmaze’ and a high‐lysine mutant fitted the expected 3:1 ratio. The high level of lysine and the floury endosperm may be controlled by the same gene.
Introgression of a gene restoring fertility to CMS (Trachystoma) Brassica juncea and the genetics of restoration
Authors: Kirti P. B. , Baldev A. , Gaikwad K. , Bhat S. R. , Kumar V. Dinesh , Prakash S. , Chopra V. L. 
Published: April 2006

AbstractA dominant gene restoring fertility to a cytoplasmic male sterile (CMS) line of Brassica juncea was derived from the somatic hybrid Trachystoma ballii+B. juncea. Its introgression resulted from forced pairing between chromosomes of the cultivar ‘Pusa Bold’ and chromosomes of the fusion hybrid. Segregation ratios of this fertility restorer gene followed a monogenic pattern. The introgression of the fertility restorer gene did not cause any abnormalities, such as reduced fertility; pollen and seed fertilities of the restored plants were over 90%. Restored fertile and CMS plants exhibited similar Southern hybridization patterns when probed with the mitochondrial probe atp6.
Inheritance and linkage of a gene for testa‐imposed seed dormancy in faba bean (Vicia faba L.)
Authors: Ramsay G. 
Published: April 2006

AbstractSeed dormancy in the grain legumes may interfere with germination in some situations, yet is not well described. Dormancy in faba bean (Vicia faba L.) was investigated to determine the mode of inheritance and whether the gene or genes controlling this trait are linked to other genes. Seeds produced by 235 recombinant inbred lines at the F6 generation were used for this study. The parents were the cultivar ‘Optica’ and 172, an Afghanistan landrace which possesses extended seed dormancy. Germination was scored on a seed sample from each recombinant inbred line. Segregation patterns indicated that the trait is monogenic. This gene, named doz, is linked to a gene controlling anthocyanin and proanthocyanidin synthesis, sp‐b, with the genetic distance estimated to be about 25 cM. No associations were detected between seed dormancy and pod dehiscence, seed lustre or mean seed weight. The implications of the persistence of a gene for seed dormancy in the gene pool of V. faba for the introgression of traits from landraces and cultivars possessing dormancy and for the origins of domesticated V. faba are discussed.
Drought tolerance screening for potato improvement
Authors: Ranalli P. , Candilo M. di , Bagatta M. 
Published: April 2006

AbstractSix potato genotypes including ‘Desiree’ and five breeding clones (2/14, 95C, 125B, 3589, 4056) were grown in the field under well‐watered and stress conditions. The stress response of leaf tissue was assessed 8 and 12 weeks after plant emergence (WAE) by measuring canopy temperature and chlorophyll α fluorescence induction kinetics in detached leaves. Under drought‐stress conditions, chlorophyll α fluorescence dropped in clones 2/14 and 4056, remained constant in 95C and 125B and increased in clone 3589. The canopy temperature exhibited little difference between drought and irrigated treatments in clones 95C and 125B, and significant effects in the other genotypes. This performance was interpreted in terms of tolerance to drought stress, and the potential use of canopy temperature and chlorophyll fluorescence as tools for drought screening of potato germplasm and segregant generations is discussed. The physiological properties of 95C and 125B highlighted by this study need further investigation and, if confirmed, they could be recombined with other useful agronomic characters by crossing in a breeding programme.
Effectiveness of selection at microtuber crop level in potato
Authors: Gopal J. , Minocha J. L. 
Published: April 2006

AbstractCorrelation coefficients were computed between microtuber crops and normal seed crop in order to study the selection efficiency for agronomic characters in potato at microtuber crop level. Two types of microtuber, green and white, were produced by inducing microtuberization under light and dark conditions, respectively. Genotypic differences were significant for various characters in both microtuber and normal seed crops. Green and white microtubers were equally useful for selection, judging by the crops raised from them. Selection at microtuber crop level was found to be highly effective for plant height, stem habit, tuber colour and general impression, and moderately effective for internode length, leaf length, leaflet width, stem pigment, plant vigour and tuber shape. Selection efficiency was low for tuber yield, tuber number, average tuber weight, number of nodes, number of stems, leaf colour and number of eyes. The implications of these results for potato breeding and germplasm evaluation programmes are discussed and a procedure for selecting superior genotypes at microtuber crop level is outlined.
Doubled haploid production in Turkish durum wheats using crosses with maize
Authors: Savaskan C. , Ellerbrook C. , Fish L. J. , Snape J. W. 
Published: April 2006

AbstractDurum wheats cultivated in the Middle Anatolia region of Turkey (Triticum durum cvs ‘Kunduru’, ‘Berkmen’ and ‘Cakmak’) were crossed with maize to evaluate their capacity for haploid embryo and doubled haploid (DH) plant production. A total of 2960 florets were crossed with maize and 13.7% of the florets produced haploid embryos across the three varieties. Haploid embryo and plant regeneration frequencies were highest in ‘Kunduru’, but colchicine doubling was less successful with this genotype. There were statistically significant differences between ‘Cakmak’ and other genotypes for embryo yield (P < 0.01). Overall, 52.3% of all embryos differentiated, but there were no geno‐typic differences in differentiation frequencies.
Fertility restoration of new CMS sources in sunflower (Helianthus annum L.)
Authors: Horn R. , Friedt W. 
Published: April 2006

AbstractThe development of commercial sunflower hybrids based on new CMS sources is of special interest for reducing the potential risk of vulnerability to pathogens and for increasing genetic diversity. From 263 test crosses involving nine new CMS sources, i.e. ANL1, ANL2, MAX1, PEF1, PET2, ANN1, ANN2, ANNS and ANN4, five lines were selected as potential restorers for PEF1, PET2 and ANN4. In test crosses between all nine CMS sources and these five restorer lines evaluated in 2 years, seven fully restored hybrids could be identified. These hybrids, based on ANL1, ANL2, MAX1, PEF1, PET2, and ANN4, showed good agronomic performance for plant height, days to flowering, maturity and oil content. Segregation analyses of the F2 populations indicate that a single dominant restorer gene was sufficient to restore pollen production of hybrids based on ANL2, PEF1 and PET2. For restoration of ANN4, two dominant complementary genes are required. In restoration of fertility in the crosses of ANL1 and MAX1 investigated, two dominant genes are involved each of which on its own allows the production of fertile plants.
Effects of D‐genome chromosomes on crossability of hexaploid triticale (X Triticosecale Wittmack) with maize
Authors: Inagaki M. N. , Pfeiffer W. H. , Mergoum M. , Mujeeb‐Kazi A. , Lukaszewski A. J. 
Published: April 2006

AbstractWith the aim of producing polyhaploids of hexaploid triticale, 20 genotypes from a CIMMYT breeding programme and eight D‐genome chromosome substitution lines of ‘Rhino’ were crossed with maize. In crosses between 20 triticale genotypes and maize, 15 lines produced embryos. Frequencies of embryo formation ranged from 0.0 to 5.4%, with an average of 1.1%. From a total of 200 pollinated spikes, 62 plants were regenerated. Most regenerated plants were polyhaploids with 21 chromosomes, and few aneuhaploids with 22 chromosomes were found. In crosses of triticale substitution lines with maize, all the lines produced embryos, while ‘Rhino’ produced no embryos at all. Higher frequencies of embryo formation were obtained in substitution lines with chromosomes 2D and 4D. These results suggest that D‐genome chromosomes in a triticale genetic background have the effect of increasing the frequency of polyhaploid production in triticale x maize crosses.
Molecular markers linked to rhizomania resistance in sugar beet, Beta vulgaris, from two different sources map to the same linkage group
Authors: Giorio G. , Gallitelli M. , Carriero F. 
Published: April 2006

AbstractRhizomania, one of the most important diseases of sugar beet, is caused by beet necrotic yellow vein virus, a Furovirus vectored by the fungus Polymyxa betae Keskin. Reduction of the production losses caused by this disease can only be achieved by using tolerant cultivars. The objective of this study was the identification and mapping of random amplified polymorphic DNA (RAPD) markers linked to a rhizomania resistance gene. The RAPD markers were identified using bulked segregant analysis in a segregating population of 62 individuals derived by intercrossing plants of the resistant commercial hybrid GOLF, and the resistance locus was positioned in a molecular marker linkage map made with a different population of 50 GOLF plants.The resistance locus, Rr1, was mapped to linkage group III of our map of Beta vulgaris L. ssp. vulgaris, which consisted of 76 RAPDs, 20 restriction fragment length polymorphisms (RFLPs), three sequence characterized amplified regions (SCARs) and one sequence tagged site (STS). In total, 101 molecular markers were mapped over 14 linkage groups which spanned 688.4 cM with an average interval length of 8.0 cM. In the combined map, Rr1 proved to be flanked by the RAPD loci RA4111800 and AS71100 at 9.5 and 18.5cM, respectively. Moreover, in our I2 population, we found that a set of markers shown by Barzen et al. (1997) to be linked to the ‘Holly’ type resistance gene was also linked to the ‘GOLF’‐type resistance gene. These results appeared to indicate that the rhizomania resistance gene present in the GOLF hybrid could be the same gene underlying resistance in ‘Holly’‐based resistant genotypes. Two other explanations could be applied: first, that two different alleles at the same locus could have been selected; second, that two different genes at two different but clustered loci underwent the selection process.
Molecular characterization of fertile and sterile cytoplasms in Beta spp.
Authors: Sadoch Z. , Goc A. 
Published: April 2006

AbstractMitochondrial DNA (mtDNA) from sugar beet carrying fertile (F) and male sterile (CMS) cytoplasms, and from male sterile accession of Beta maritima collected in Brittany (France) were characterized and compared by restriction fragment length polymorphism (RFLP) and Southern hybridization with coxII. The F and CMS cytoplasms could be clearly distinguished from each other by RFLP when XhoI, EcoRI and BamHI endonucleases were used. Southern hybridization with the coxII gene provided further evidence that mitochondrial genome organization differs between fertile and sterile plants. All cytoplasmic male sterile lines from different breeding stations showed the same restriction and hybridization patterns, which confirms the uniformity of mitochondrial genomes within the materials used for hybrid seed production in several European countries. No visible differences were found between the maintainer lines studied. However, comparisons of XhoI restriction profiles of mtDNA from maintainer lines and from fertile monogerm populations revealed slight differences, which were reflected by the appearance of a unique 0.9 kb fragment in the latter.Analysis of mtDNA from male sterile plants of the wild beet B. maritima showed different restriction and hybridization patterns in comparison with normal and sterile sugar beet cytoplasms. This shows the unique nature of cytoplasmic male sterility in this species.