bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic variation among European maize inbreds for resistance to the European corn borer and relation to agronomic traits
Authors: Schulz B. , Kreps1 R. , Klein D. , Gumber R. K. , Melchingeru A. E. 
Published: April 2006

AbstractThe univoltine European corn borer (ECB) has become a major limiting factor for maize (Zea mays L.) production in central Europe. The objective of this study was to survey the genetic variation for ECB resistance in European elite maize germplasm. Eighteen flint and 23 dent inbreds were screened under artificial ECB infestation at two locations in 1993 and 1994. Resistance was assessed by damage rating of broken plants, measurement of tunnel length in dissected stalks, and yield reduction in infested plots relative to insecticide‐protected control plots. Flint lines showed significantly greater means for damage rating than dent lines with grain yield reduction of 35% and 24%, respectively. Significant genotypic variances among lines and high heritabilities were found for agronomic traits and damage rating. Heritabilities were intermediate for tunnel length and relative grain yield. Significant associations of days to silking, ear dry matter content, and dry matter yield of the whole plant with damage rating and tunnel length suggested a better resistance in late‐maturing, high‐yielding inbreds. Genotypic correlations of relative grain yield with tunnel length and damage rating ranged between −0.46 and −0.72. Partial correlations, eliminating the effect of flowering time, confirmed these associations. Damage rating of stalks is the most suitable trait for evaluation of ECB damage owing to its high heritability and easy recording. Tunnel length below the primary ear is a useful trait for assessing antibiosis because it is not correlated with days to silking. Inbreds with extreme resistance and susceptibility were identified which can be used as parents for establishing breeding and QTL mapping populations.
Localization of a resistance gene and identification of sources of resistance to barley leaf stripe
Authors: Thomsen S. B. , Jensen H. P. , Jensen J. , Skou J. P. , Jørgensen J. H. 
Published: April 2006

AbstractIn order to determine more precisely the location of the barley leaf stripe gene, called the ‘Vada‐resistance gene’, on barley chromosome 2, 63 chromosome‐doubled barley lines were tested. Using data on known chromosome 2 genetic markers, the ‘Vada‐resistance gene’ was estimated to be located between the markers MSU21 and Xris45b, and at a distance of about 20% recombination from the powdery mildew resistance gene MILa. We suggest that the ‘Vada‐resistance gene’ is designated Rdg1a and that all former leaf stripe resistance gene designations should be rejected.To identify possible new sources of resistance, 11 barley cultivars/lines known to possess leaf stripe resistance and originating from different parts of the world, were tested with one Danish and two Syrian isolates of the leaf stripe fungus. Three apparently genetically different sources of race‐specific resistance were found. The ‘Vada‐resistance’ in the cultivar ‘Golf was effective against seven out of eight isolates’ populations of the leaf stripe fungus differing in geographical origin.
Identification of RAPD markers closely linked to the mlo‐locus in barley
Authors: Manninen O. M. , Turpeinen T. , Nissilä E. 
Published: April 2006

AbstractDeveloping resistance to powdery mildew, Erysiphe graminis f.sp. hordei, is a major goal of many barley breeding programmes. Several resistance genes have been tagged or mapped with molecular markers. The mlo gene confers durable resistance towards all known isolates of the pathogen. In this study, RAPD markers and bulked segregant analysis were used to determine PCR‐based markers linked to the mlo‐locus. Sixty doubled haploid lines from a cross between an isogenic line of ‘Ingrid’ carrying the mlo11 allele and a susceptible cv. ‘Pokko’ were used as plant material. Seven linked RAPD markers were found, the closest lying 1.6 cM away from the resistance gene. When eight barley varieties were assayed for the presence of this band, F4‐980, it was found in the resistant varieties but not in the susceptible ones. The linked marker bands could be amplified from DNA‐samples prepared by using three different methods, including a quick squash technique. PCR‐based markers linked to the resistance gene can be used as tools for selection in breeding programmes.
Inheritance and chromosome location of Alp, a gene controlling aluminum tolerance in ‘Dayton’ barley
Authors: Minella E. , Sorrells M. E. 
Published: April 2006

AbstractAluminum (Al) toxicity is a major limiting factor in acid soils and more adequate genetic tolerance is needed to improve barley adaptation and production in affected regions. To study the inheritance and chromosome location of the Alp gene controlling Al tolerance in ‘Dayton’ barley the primary trisomics of sensitive ‘Shin Ebisu 16’ were crossed to ‘Dayton’. Parental, F1 and F2 seedlings were grown in nutrient solution containing 0.03, 0.06 and 0.09mM Al. and classified for tolerance by haematoxylin staining of the roots. In diploid F2 progeny, Alp was inherited as a single gene, dominant at 0.06mM and recessive at 0.09 mM concentrations, as indicated by the 3:1 and 1:3 (tolerant: sensitive) segregation ratios, respectively. Segregation of the trisomic Frderived F2 seedlings at 0.06mM Al deviated significantly from the 3:1 only for the triplo 4/‘Dayton’ cross. Data for this cross fit the expected trisomic ratios, indicating that the Alp gene is distally located from the centromere on chromosome 4. These results confirm that tolerance is simply inherited, but expression of tolerance is dependent on Al concentration and allele dose.
Genetic and phenotypic correlations in plantain‐banana euploid hybrids
Authors: Ortiz R. 
Published: April 2006

AbstractThe objective of this work was to determine intraclass correlations for growth and yield traits, as well as associations between them, in segregating hybrids. Diploid, triploid and tetraploid hybrids were obtained from triploid‐diploid crosses between plantains and bananas. These hybrids were evaluated as plants and as ratoon crops on a humid forest site. Significant differences between ploidy within crosses were observed for most traits. The tetraploids were taller, had longer production cycles but a shorter fruit filling time, and heavier bunches than the diploids. There were significant differences between clones of the same ploidy within crosses. Hence, individual selection within ploidy will be effective for the improvement of plantain. Most of the bunch and fruit traits were positively and significantly associated, especially at the tetraploid level. Selection for large fruit at the diploid and tetraploid levels may lead to heavy fruits, thereby resulting in hybrids bearing heavy bunches. Significant and positive correlations between plant height and bunch weight at the tetraploid level suggest that selection of dwarf plantains with heavy bunches may be difficult.
Yield performance of interspecific F1 hybrids of the greek mountain tea, Sideritis spp. L.
Authors: Goliaris A. H. , Roupakias D. G. 
Published: April 2006

AbstractInterspecific F1 hybrids were produced after artificial intercrossing of six Sideritis species indigenous to Greece, namely: S. athoa, S. euboea, S. syriaca, S. raeseri, S. scardica, S. clandestina and a cultivated clone of S. raeseri. It was found that all species cross with each other, but the level of crossability varied with the cross‐combination. In the yield evaluation experiments, the interspecific hybrids with a common female parent were considered as a group. It was observed that yield during the year of establishment was relatively low, but the interspecific hybrids out‐yielded the control in both fresh and dry weight. All hybrids produced higher yields in the following years and their productivity started to decline after the fifth year. All hybrids produced higher yields than the control in all six years of the experiment. The highest yield over the years, in fresh and dry weight, was produced by the group Sideritis raeseri cultivated clone (cc) ×Sideritis spp. This yield, however, was not always significantly different from the yield produced by the second in the rank group (S. clandestina×Sideritis spp.). A high correlation (r > 0.99) between fresh and dry weight was observed. The two groups with the highest yield also had the highest essential oil content. In addition, all the interspecific hybrids had a higher essential oil content than the control species. Furthermore, the essential oil content of the selected individual hybrid plants ranged between the midparental value to a value higher than the high‐parental species, indicating an additive and dominance gene action. It was also found that the content of the essential oil in the seven most important components (pinene, lemonene, cynene, menthone, copaene, caryophyllene and valerianic ester) varied from hybrid to hybrid. Given that Sideritis reproduces mainly asexually, the direct use of individual interspecific hybrids with higher yield and content in essential oil than the control species is possible in cultivation.
Resistance of early‐maturing European maize germplasm to sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV)
Authors: Kuntze L. , Fuchs E. , Grüntzig M. , Schulz B. , Klein D. , Melchinger A. E. 
Published: April 2006

AbstractSugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are the most important viruses of maize in Europe. In field and greenhouse experiments, 122 early‐maturing European maize inbreds (45 flint and 77 dent lines) were evaluated for their reaction to artificial inoculation by SCMV and MDMV. Three dent inbreds (D21, D32, FAP1360 A) with complete resistance and four dent inbreds (D06, D09, R2306, FAP1396A) with partial resistance against both potyviruses under both greenhouse and field conditions were identified. All other inbreds were highly susceptible to both SCMV and MDMV. Selection for virus resistance in maize breeding could be performed with only one virus at a time because all inbreds resistant to SCMV were also resistant to MDMV. Rank correlations between percentages of infected plants in greenhouse and field trials ranged from 0.51 to 0.72 for both SCMV and MDMV, suggesting that prescreening of breeding materials for virus resistance can be performed in the greenhouse but final evaluation in multilocation trials in the field is recommended.
Evidence for genetic control and media effect on haploid regeneration in the anther culture of hexaploid wheat (Triticum aestivum L.)
Authors: Moieni A. , Lokos‐Toth K. , Sarrafi A. 
Published: April 2006

AbstractCrosses were made between seven hexaploid wheat genotypes. Twenty‐one F1 hybrids and their parents were grown in a greenhouse with 16 h day/8 h night at 25°C and 15°C, respectively. The experiment was a complete randomized block design with three replications. Each replication consisted of one pot with three plants. Anther culture was performed in two different induction media (CHB and W14) and androgenetic traits were studied. Statistical analysis was carried out separately for each induction medium. Genetic variation was highly significant for androgenetic traits and the best parent (IBPT 19) produced 68 embryos and 9.3 green plants per 100 anthers in CHB medium. Genetic components were affected by induction media and some components were significant in one medium and non significant in the other. General combining ability (GCA) was significant for all androgenetic traits, except for albino plant regeneration in both media and total plant regeneration in CHB medium, whereas specific combining ability (SCA) was not significant for the traits studied. Narrow sense heritability was high for embryo induction frequency and green and total plant regeneration. All our results indicate that androgenetic parameters can be improved in hexaploid wheat by genetic means.
Evidence of allelism between genes Pm8 and Pm17 and chromosomal location of powdery mildew and leaf rust resistance genes in the common wheat cultivar‘Amigo'
Authors: Hsam S. L. K. , Zeller F. J. 
Published: April 2006

AbstractTIBL‐1RS wheat‐rye translocation cultivars utilized in wheat programmes worldwide carry powdery mildew resistance gene Pm8. Cultivar‘Amigo’possesses resistance gene Pm17 on its TIAL‐1RS translocated chromosome. To be able to use Pm17efficiently in breeding programmes, this gene was transferred to a TIBL‐1RS translocation in line Helami‐105, and allelism between Pm8 and Pm17was studied. The progenies of the hybrids in the F2 generation and F3 families provided evidence that the two genes are allelic. Genetic studies using monosomic analyses confirmed that in cultivar‘Amigo', Pm17 and leaf rust resistance gene Lr24 are located on a translocated chromosome involving 1 A and 1B, respectively.
Genetics of resistance to kernel infection by Aspergillus flavus in maize *
Authors: Zhang Y. , Kang M. S. , Magari R. 
Published: April 2006

AbstractAlthough kernel infection by Aspergillus flavus Link ex Fries and subsequent pre‐harvest aflatoxin contamination of maize (Zea mays L.) grain are major production problems in the south‐eastern United States and elsewhere in the world, limited progress has been made in developing and identifying sources for resistance. Genetics of kernel infection by A. flavus remains poorly understood. A 10‐parent diallel experiment was conducted in 1992 and 1994 to study the genetic nature of percentage kernel infection (PKI) by A. flavus. General combining ability (GCA), specific combining ability (SCA), and reciprocal mean squares for PKI were significant. The GCA and SCA sums of squares were about equal. The GCA, SCA, and reciprocal effects varied across years, which implied that percentage kernel infection was greatly influenced by environments. The percentage kernel infection was always greater when Mo 17 was the male parent in a cross than when it was the female parent. The percentage kernel infection mean for female Mo 17 was 38.5% lower than that for male Mol7. Similarly, percentage kernel infection mean for female L668 was 23.7% lower than that for male L668. The use of inbred lines L729 and B73 as female parents should be avoided, as they showed significant, positive maternal reciprocal effects.
Genetic control of alcohol dehydrogenase, malate dehydrogenase, and phosphoglucomutase isozymes in lima bean (Phaseolus lunatus L.)
Authors: BI I. Zoro , Maquet A. , Wathelet B. , Baudoin J. P. 
Published: April 2006

AbstractA suitable electrophoretic separation method for alcohol dehydrogenase (ADH). malate dehydrogenase (MDH). and phosphoglucomutase (PGM) from P. lunatus has been developed. Two loci (Adh‐2 and Pgm‐2) showed codominant inheritance and fitted Mendelian ratio. ADH isozyme banding patterns indicate a dimeric quaternary structure. while those of PGM were in agreement with a monomeric nature. The cytoplasmic location of two MDH isozymes (Mdh‐1 and Mdh‐2) selectively inactivated by homogenization in an ascorbic acid solution was demonstrated. However. distorted ratios were observed for Mdh‐2 segregation. On the basis of MDH isozyme banding patterns observed in five progeny families, il is suggested that this enzyme system is a dimeric protein encoded by at least three codominant genes (Mdh‐1 .Mdh‐2 and Mdh‐3). Joint segregation tests between pairs of segregating loci (Adh‐2, Mdh‐2, and Pgm‐2) indicated that each of them is inherited independently.
Genetic and non‐genetic factors affecting germination and vitality in spring barley seed
Authors: Chloupek O. , Ehrenbergerová J. , ŠEVČIK R. , PAŘIZIK P. 
Published: April 2006

AbstractGermination of eight spring barley varieties, grown in two years at eight different locations in State varietal trials in the Czech republic, was analysed. All the combinations were tested under optimal conditions for germination as recommended by ISTA and also at low temperatures (5 and 10°C), and underwater stress (‐ 2 and ‐ 4 bar). Germination under low temperature and water stress was considered as a character of seed vitality.Varieties in nearly all experiments were a significant source of variation and their relative contribution to the total variation was higher for vitality (5.7–38.7%) than for germination (2.0–4.3%). However, the percentage of germination were not related to the percentage of vitality.The location in nearly all the experiments caused the greatest variation and the impact was greater for germination than for vitality. Provenance effects were different for germination and for vitality; grains harvested in the lowland had the highest germination values, but not the highest vitality values.The results should encourage breeding for seed vitality and some reconsideration of provenance effects on seed vitality.
Comparison of salt tolerance of GPert and non‐GPert barleys
Authors: Pakniyat H. , Thomas W. T. B. , Caligari P. D. S. , Forster B. P. 
Published: April 2006

AbstractA salt tolerance experiment was performed to study the effect of the GPert mutation in different genetic backgrounds of spring barley, Hordeum vulgare. L. Twenty‐one lines carrying GPert along with 20 related non‐GPert lines were grown for 4 weeks in low salt (25 mol m−3 NaCI) and salt stress (175 mol m−3 NaCI) hydroponic cultures. Shoot Na+ content was taken as a measure of salt tolerance. Salt tolerance of the two groups (GPert versus non‐GPert) was compared, as was the performance of individual GPert lines with their non‐GPert parental lines. The results show that GPert has a general positive effect on salt tolerance in reducing shoot Na+ content, but that this is regulated by genetic background.
Prospects of polyploidizing cassava, Manihot esculenta Crantz, by unreduced microspores
Authors: Nassar N.M. A. , Freitas M. 
Published: April 2006

AbstractEleven interspecific hybrids of cassava with the wild relatives Manihot glaziovii, M. pseudoglaziovii. M. dichotoma and M. anomala were examined to detect unreduced microspores. The frequency of dyads and triads was counted, as well as pollen viability. Of these hybrids, the second generation progeny of cassava×M. glaziovii showed a high frequency of unreduced microspores (3.7%) permitting their selection for further manipulation of this character. An association of vegetatively‐reproduced genotypes and the occurrence of unreduced microspores has also been observed.
Genetic analysis of resistance to Phoma tracheiphila in three Citrus and Poncirus progenies
Authors: Recupero G. Reforgiato , Gentile A. , Russo M. P. , Domina F. 
Published: April 2006

AbstractMal secco is a serious tracheomycosis, caused by the fungus Phoma tracheiphila (Petri) Kanc, et Ghik., which attacks some species of the genus Citrus. The considerable amount of time and space required to evaluate host plant response has discouraged research on the mechanism of inheritance involved in the susceptibility to this disease. The aim of the present work was to study segregation of the resistance trait in three progenies obtained by crossing Citrus latipes (Swing.) Tan., as a female parent, with the male parents Poncirus trifoliata (L.) Raf., C.aurantium L. and C. volkameriana Pasq. Resistance determination was based on natural infections observed over 10 years. Results allowed us to hypothesize three alternative genes (A, B and C) which determine dominant resistance as opposed to susceptibility: the presence of a single allele can thus confer resistance. In addition, we suggest the existence of a fourth gene which, in conditions of dominance, is able to determine susceptibility by nullifying the action of the dominant B allele. Response to the pathogen was also associated with the production of chitinase a PR (pathogenesis‐related) protein reported to be present in great quantities in mal secco‐resistant Citrus genotypes. Segregation analysis of one F2 progeny confirmed the hypothesis that the resistance trait is controlled by at least two dominant genes. Further evidence is needed to ascertain whether this hypothesis is applicable to other Citrus species, in which the possibility of other genetic mechanisms being implicated cannot be ruled out, thus making the genetic basis of mal secco resisance more complex.
Agronomic performance and molecular assessment of tissue culture‐derived barley lines
Authors: Todorovska E. , Trikonova1 A. , Petrova M. , Vitanova1 Z. , Marinova E. , Gramatikova3 M. , Valcheva D. , Zaprianov3 S. , Mersinkov3 N. , Atanassov A. 
Published: April 2006

AbstractIn order to assess the genetic variability among regenerants. field trials were conducted with 64 barley lines derived from tissue culture (TCD lines) of four Bulgarian barley varieties. The results indicate that the agronomic performance was altered by tissue culture regeneration and the frequency of variation was cultivar dependent. Seven TCD lines showing desirable agronomic characters were selected in the SC16 progeny. Molecular markers (protein, restriction fragment length polymorphism (RFLP) and random amplified polymorphic DNA (RAPD) have used applied to determine the variability induced by tissue culture. Polymorphism was detected in sequences coding for C‐hordeins in line 70 derived from cv.‘Jubiley’Two lines from cv.‘Ruen’exhibited polymorphic bands after hybridization with a mitochondrial DNA probe. RAPD assays have been carried out using 20 different l0‐mer primers. Heritable polymorphisms in several TCD lines have been observed.
Comparative osmotic adjustments in barley and tetraploid wheats
Authors: Teulat1 B. , Rekika D. , Nachit M. M. , Monneveux P. 
Published: April 2006

AbstractFive barley (Hordeum rulgare L.), five durum wheat (Triticum turgidum concar. durum L.) and one wild emmer wheat (Triticum turgidum conrar dicoccoides) genotypes from different origins and differing for drought tolerance and potential yield, were studied for their osmotic adjustment capacity at the same stage and under similar water stress conditions. Differences for water status parameters between barley and tetraploid wheat genotypes were noted and discussed. The lowest osmotic adjustment capacities were noted in drought susceptible varieties, while a high capacity was found in genotypes exhibiting a high yield stability across contrasting environments. Relative water content, leaf osmotic potential and accumulation of soluble sugars were found to be highly related with osmotic adjustment: they could be used as criteria for a rapid evaluation of osmotic adjustment in segregating populations.
About the origin of 1RS.1BL wheat‐rye chromosome translocations from Germany
Authors: Schlegel1 R. , Korzun V. 
Published: April 2006

AbstractIn order lo investigate the origin of two of the German 1RS. 1BL wheat‐rye translocations used world‐wide in breeding, a number of DNA probes were considered which (a) were critical for the short arm of the rye chromosome 1 R and (b) should show a specificity for the gene pool of Petkus rye. The DNA probe CDO580 was revealed as a specific one. (1) It clearly differentiated 1RS.1AL (‘Amigo’). 1RS.lBL (‘Salmon’) and 1RS.1DL (‘Gabo’) from the two German sources. (2) Both translocation wheats deriving from the Weihenstephan (Munich) and from the Salzmünde (Halle/S.) origin showed an identical DNA fragment which was typical for the gene pool of Petkus rye. It is supposed that both German sources have one progenitor in common.