bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nematode Resistance Derived from Wild Beet and its Meiotic Stability in Sugar Beet
Authors: Brandes Andrea , Jungand C. , Wricke G. 
Published: April 2006

AbstractThree different karyotypes of sugar beet with resistance against the beet cyst nematode (Heterodera schachtii) have been investigated. These comprised monosomic addition lines (2n = 19) with one complete chromosome from B. patellarris or B. procumbens, one line with a chromosomal fragment added to the normal sugar beet chromosome complement (2n =18 + fragment) and one diploid line (2n = 18). The fragment originated from a B. procumbens chromosome since during meiosis it formed a univalem. It carries the gene for nematode resistance. Meiotic disturbances like univalems. laggards, anaphase I bridges, fragments and micronuclei were observed in all resistant genotypes. These may result in an exclusion of the chromosome fragment carrying the resistance from the rest of the genome. In the diploid resistant line, a chromosome with a translocation could be distinguished from the other B. vulgaris chromosomes. Meiotic irregularities also appeared in diploid resistant types and are one main reason for low transmission of the resistance. Tin‐relationship between meiotic stability and the transmission rate of the resistance gene is discussed.
Seed Color Inheritance in Brassica carinata A. Braun, Cultivar S‐67
Authors: Getinet A. , Rakow G. , Downey R. K. 
Published: April 2006

AbstractThe inheritance of seed color was studied in the brown seeded Ethiopian mustard (Brassica carinata A. Braun), cultivar S‐67. Seed color was controlled by a single gene pair. The heterozygous condition resulted in light yellow‐brown set‐d indicating incomplete dominance [semidominance] of brown over yellow. The homozygous recessive condition resulted in yellow seed. The significance of these findings in relation to seed color inheritance in other Brassica species is discussed.
Identification of Maintainer Genes in Brassica napus L. for the Male‐Sterility‐Inducing Cytoplasm of Diplotaxis muralis L.
Authors: Pellan‐Delourme R. , Renard M. 
Published: April 2006

AbstractMale fertility of F1 interspecific hybrid plants derived from crosses between cytoplasmic male‐sterile Brassica campestris in Diplotaxis muralis cytoplasm and 147 B. napus cultivars was Investigated. F1, plants obtained, from crosses with the B. napus cultivars‘Mangum’and‘Hinchu’were male‐sterile while F1 plants derived from all other crosses were male‐fertile. This indicated that these two cultivars carried maintainer genes far the male‐sterility‐inducing cytoplasm of D. muralis. Sterility was stable In plants derived from backcrosses of male‐sterile F; plants with‘Mangun and‘Hinchu’but the seed set of backcross plants was low. With restorer genes readily available in B. napus, these findings could lead to the development of a new cytoplasmic male sterility system for the breeding of B. napus hybrid cultivars.
Joint Selection for High Yield and Low Sensitivity in Winter Wheat (Triticum aestivum L.)
Authors: Hughes W. G. , Westcott B. , Sharp P. L. 
Published: April 2006

AbstractEarly generation yield trials of families from a set of winter wheat crosses were grown in three contrasting environments chosen to represent differences in two important macro‐environmental variables affecting the wheat, crop in Eastern England. Joint selection for high yield and low sensitivity to these macro‐environmental variables over two seasons using the procedure of Brumpton et al. (1977) resulted in a group of genotypes which exhibited a much wider yield range than would have resulted from selecting for yield in each ‐environment separately. In spite of this, the top performing lines an yield trials grown in each of the environments during the next season exhibited good yield and stability over all three environments, demonstrating the feasibility of such a method for winter wheat breeding.
Response to Selection for Resistance to Macrophomina and Xanthomonas and its Association with Seed Colour in Cowpea*
Authors: Higuera A. , Murty B. R. 
Published: April 2006

AbstractIn cowpea, black seeded types are supposedly resistant to Macrophomina. A study was undertaken to verify the association of seed colour with resistance to Macrophomina and Xanthomonas and to examine the response over three cycles of selection for such resistance along with seed yield, determinate habit and synchronous flowering in five black‐and three white‐seeded cowpea varieties. Selection was done between and within progenies under heavy natural incidence of both pathogens supplemented by artificial inoculation of Macrophomina using the toothpick method at flower primordial stage. Among 414 single plant progenies in the first cycle all 193 white‐seeded progenies from three different varieties were highly susceptible to both pathogens, with considerable variation among the black‐seeded ones. All the black‐ and white‐seeded progenies derived from the same variety‘Floricream’were highly susceptible. Multivariate analysis for five characters in the ten best progenies after two selection cycles revealed significant genetic diversity between the progenies. Selection was successful with the isolation of three productive progenies resistant: to both diseases. The results indicated that seed colour had no influence on resistance m this material and that simultaneous improvement of seed yield, plant type and disease resistance could be achieved.
Cytogenetic Studies of Crosses between Lolium multiflorum Lam. and Festuca arundinacea Schreb. III. The Generations C1, C2 and C3
Authors: Kleijer G. 
Published: April 2006

AbstractMeiotic observations of 56‐chromosome plants of the C1, C2 and C3 generations of the amphidiploid Lolium multiflorum × Festuca arundinacea showed that most of the chromosomes paired as bivalents. However, uni‐ and multivalents were frequently observed. No difference in meiotic regularity and stability could be detected between the different generations. The average chromosome number and; the percentage of 56‐chromosome plants decreased with increasing generations. The direct use of the 56‐chromosome amphidiploids of L. multiflorum and F. arundinacea in a breeding programme appears to be quite difficult, but these plants can be used in a backcross programme with Lolium and Festuca.
Regeneration of Pea (Pisum sativum L.) Plantlets by in vitro Culture of Immature Embryos
Authors: Natali L. , Cavallini A. 
Published: April 2006

AbstractPlant regeneration was achieved from immature embryo‐derived, calli of Pisum sativum. Embryo axes were separated from cotyledons and cultured on different media containing BAP and NAA until plantlet regeneration. Rooting of the plantlets was obtained on MS medium supplemented with 2 mg/1 IBA. Frequency of regeneration was shown to be under the influence of the genotype. Histological preparations showed de novo origin of the shoots via organogenesis. Out of 2C regenerated plantlets, 11 were diploids (2n = 14) arid 9 aneusomatic (chromosomal mosaics) with chromosome numbers ranging from 12 to 16.
An Evaluation of Hordeum vulgare L. ×Psathyrostachys fragilis (Boiss.) Nevski Crosses for Doubled Haploid Barley Production
Authors: Pickering R. A. 
Published: April 2006

AbstractInvestigations were carried out to assess the suitability of the intergeneric cross Hordeum vulgare×Psathyrostachys fragilis for haploid barley production. H. vulgare cvs. ‘Emir’ and ‘Vada’ were each pollinated with P. fragilis P.I. 343192 and plants regenerated from embryos cultured on a modified B5 medium. Seed sets on ‘Vada’ were significantly lower than on ‘Emir’, and all the planes from ‘Vada’×P. fragile remained hybrid. Several of these flowered but there was little pairing between the parental chromosomes. Most of the plants from ‘Emir’×P. fragilis died, as seedlings but 3 plants developed into haploid barley. Because of the practical limitations of pollen availability from P. fragilis and the inconsistencies in haploid plant formation, it is unlikely that the cross will prove as valuable as that between H. vulgare×H. bulbosum for a doubled haploid barley programme.
The Response of Anther Culture in a Genetically Wide Material of Winter Wheat (Triticum aestivum L.)
Authors: Andersen S. B. , Due I. K. , Olesen A. 
Published: April 2006

AbstractIn a screening experiment with 215 different winter cultivars of Triticum aestivum L. for response in anther culture, pollen embryos or callus were obtained from 200 different cultivars and green plants from 93 different cultivars. On average, from the whole material, 1.3 green plants were obtained per 100 anthers cultured. Variance components estimated from replicates with selected parts of the plant material indicated that for the formation of pollen embryos from anthers, interactions between genotypes and replications were dominating, accounting for 45 to 50 per cent of the variation. Main effects from genotypes were less prominent, accounting for 25 to 30 per cent of the variation, and the replications showed relatively little effect, accounting, for about 4 to 12 per cent of total variation. Regeneration of plants from pollen embryos or callus was not significantly influenced by either genotype or replicates. The frequencies of plants regenerated being green, however, were influenced from both genotype and environments contributing 42.5 and 34.9 per cent of the total variation respectively, while only minor interactions between genotype and environments were indicated for this character.
Doubled Haploids of Cocoa (Theobroma cacao L.) 2. Observations of Monogenic and Polygenic Characters
Authors: Lanaud C. 
Published: April 2006

AbstractThe expression of monogenic and polygenic characters has been studied in families of spontaneous haploids of cocoa which nave been doubled with colchicine. Segregation of six enzyme markers, heterozygous in the various parent clones, has been analysed in the doubled haploids for alcohol dehydrogsnase (ADH), malate dehydrogenase locus B (MDH‐B), isocitrate dehydrogenase (IDH), acid phosphatase (ACP), phosphoglucomutase (PGM) and phosphoglucose isomerase (PGI). Nine of the eleven families showed a Mendelian‐type segregation, two presented distortions but all alleles were found in the haploid progenies.Polygenic characters were expressed with great variability: A few DHs showed similar or even higher values than their parents for individual characters, but the majority were lower, and large depressions could be seen for the group of characters studied.These results have consequences for the use of doubled haploids of cocoa which must both give a sure production of hybrid seeds and be good progenitors; no prediction of their value as progenitors seems possible after observation of their own characteristics and the only selection made from these plants will be a propos their characters directly involved in seed production. These selected doubled haploids will subsequently have to be tested as progenitors.
Cytological Study of Callus and Regenerated Plants of Sunflower (Helianthus annuus L.)
Authors: Cavallini A. , Lupi M. C. 
Published: April 2006

Abstract In vitro culture of shoot apical meristems of Helianthus annuus was studied to determine the cytological condition of calli and regenerated shoots. A broad chromosome mosaicism (aneusomary) in bath callus and regenerated shoots was found, reflecting the cytological conditions of the explain. During in vitro plant development, a diplontic selection took place that was more rapid when very precocious in vitro flowering occurred.
Multiple Endopeptidasen als biochemische Marker für die Resistenz von Winterweizen gegenüber Pseudocercosporella herpotrichoides (Fron) Deighton
Authors: Vahl U. , Müller G. , Thiele A. , Thiele M. 
Published: April 2006

AbstractMultiple endopeptidases as biochemical marker for resistance of winter wheat to Pseudocercosporella herpotnchoides (Fron) Deighton. Electrophoretic patterns of primary leaf endopeptidases in breeding material derived from crosses between different winter wheat genotypes and amphidiploids (Triticum turgidum×Aegilops ventricosa) were compared with those of cultivars susceptible to Pseudocercosporella herpotrichoides. The results indicate that the multiple endopeptidase EP‐1 coded by Wheat chromosome 7 D is absent in the international known lines ‘VPM 1’ and ‘Roazon’ and in all 24 winter wheat selections with increased resistance to P. herpotrichoides.A close relationship between the absence of EP‐1 and the introduction of Aegilops ventricosa resistance is assumed. The use of this biochemical marker in wheat breeding is proposed.
The Grain Quality of Landraces of Wheat as Compared with Modern Cultivars
Authors: Blum A. , Sinmena Bebi , Golan G. , Mayer J. 
Published: April 2006

AbstractLandraces of tetraploid and hexaploid wheat from the Northern Negev in Israel were evaluated over two years for their grain quality attributes. Twenty‐one populations of tetraploid wheat (Triticum durum, represented by 56 accessions) and 8 populations of hexaploid wheat (T. aestivum and T. compactum, represented by 13 accessions) were compared with 3 and 4 modern improved Israeli cultivars of tetraploid and hexaploid reheat, respectively. This comparison allowed to estimate the progress made in the improvement of gram quality m present‐day cultivars.Except for grain protein content in the hexaploids, significant variation was revealed among landraces in kernel weight, protein content (tetraploids), sedimentation, mixograph score and carotin content. The best modern cultivars were comparable to the best landraces in kernel weight and carotin content (tetraploids), indicating that modern wheat breeding maximized kernel weight and carotin content, as compared with the tested landraces. Gram protein content and/or quality was not maximized in modern cultivars and its improvement was deemed possible by introgression from the best landraces in this respect.
Effects of Competition upon the Productivity of White Clover‐Perennial Ryegrass Mixtures. Genetic Analysis
Authors: Hill J. , Michaelson‐Yeates T. P. T. 
Published: April 2006

AbstractA diallel cross amongst four contrasting white clover varieties was used to provide genetic information on those characters which affect the productivity of white clover‐perennial ryegrass mixtures when grown under a cutting‐only management regime. Generally speaking those characters recorded on the clover families and in mixtures exhibited highly significant additive and non‐ad dative genetic effects, though for1 sortie characters the latter could not be ascribed solely to dominance effects. For two of the clover characters, stolon and leaf number, the genetic picture was radically altered in mixtures by the effects of inter‐specific competition Pseudo‐genetic effects were also detected for the grass characters, bur it was suggested that the two ryegrass varieties used here were exhibiting phenotypic plasticity. As a group the four intra‐varietal crosses performed significantly better than the six intra‐varietal crosses for all clover and mixture characters. Only one of the inter‐varietal crosses had significantly positive specific combining ability effects for most characters and that was between the two long established varieties ‘S. 184’ and ‘S. 100’. The implications of these results for the breeding of white clover varieties for use in mixtures are briefly discussed.
Genetical Studies of Resistance of Powdery Mildew in Barley Lines Derived from Hordeum spontaneum Collected from Israel
Authors: Jahoor A. , Fischbeck G. 
Published: April 2006

AbstractGenetical studies on mildew resistance were carried out with Hordem spontaneum derived lines. A total of 28 lines (66 %) showed monofactorial segregation for mildew resistance, For 14 lines, a bifactorial mode of inheritance was found. In total fifty six mildew resistance genes take part in the inheritance of mildew resistance of the H. spontaneum derived lines, while the presence of known genes for mildew resistance (i.e, Ml‐a.9 and Ml‐p) was established only in two cases. Independent segregation from the Ml‐a locus was found in 10 mbnofaetorial segregating lines, The genes conditioning mildew resistance in barley lines derived from the accessions 1B‐54B, RS 170‐47, RS 20‐1. 1B‐86B, RS 145‐39 and 1B–152B of H. spontaneum were closely linked or alleles to the Ml‐a locus, but shown to be different from 15 previously identified Ml‐a alleles. It is suggested that these genes should be designated Ml‐a16, Ml‐18, Ml‐19 Ml‐20 and Ml‐a21 respectively. No recombinants were found in test crosses when both parents carried genes/alleles of the Ml‐a locus. In addition, polymorphism has been observed also for the Ml‐a locus. In 4 lines mildew resistance was conditioned by two dominant complementary genes. For one of the 2 genes, conditioning mildew resistance of line RS 42‐8 × OrioL a new locus was found located near the centromere of the long arm of chromosome 5, and should be designated Ml‐i The potential use of H. spontaneum genes for mildew resistance in barley breeding is discussed.
Breeding Progress in Grain Yield and Selected Agronomic Characters of Winter Barley (Hordeum vulgare L.) over the Last Quarter of a Century
Authors: Martintello P. , Delocu G. , Boggini G. , Odoardi M. , Stanca A. M. 
Published: April 2006

AbstractThis study gives estimates of breeding progress achieved in winter barley (Hordeum vulgare L.) since the 1960′s in grain yield and the change in several morphological traits for seventeen historically important cultivars: 12 six‐rowed and 5 two‐rowed, grouped into four epochs according to the period of major commercialization in Italy. All genotypes were evaluated across a range of soil fertility and climatic environments.The modern six‐rowed cultivars have shown a consistent increase in tillers/m2 and seeds/spike (16 and 28 %, respectively) over the local populations. In the modern two‐rowed cultivar ‘Igri’ the increase in tillers/m2 and seed weight were, respectively, 20 and 14 % snd seeds/spike decreased by 20 % over the local populations. The modern six‐rowed and two‐rowed cultivars have less lodging, are earlier and shorter than the old varieties and local populations. In the last quarter of a century, the breeding progress for gram yield has been increased by 52 and 74 kg/ ha/year or 0.75 and 1.1 % per year respectively, for six‐rowed and two‐rowed genotypes: while the gain in biomass yield in the same period was not uniform for six‐rowed cuitivars and increased by 64 kg/ha/ year or 0.46 % in two‐rowed cultivars. The grain yield improvement in the modern six‐rowed and two‐rowed cultivars is the result of a better partitioning of the photosynthetic products into the grain.
Determination of Ploidy of Single Plants and Plant Populations by Flow Cytometry
Authors: DeLaat A. M. M. , Gohde W. , Vogelzakg M. J. D. C. 
Published: April 2006

AbstractAn efficient method for the determination of the ploidy level is described, based on a measurement of the DNA content of interphase nuclei by flow cytometry. Both individual plants as well as plant populations can be used to obtain the desired DNA‐histograms Compared to conventional chromosome counting flow cytometry turned out to be highly competitive in terms of simplicity, accuracy, and costs.
Flower‐Colour Polymorphism in Lupinus pilosus in Israel
Authors: Pazy B. 
Published: April 2006

AbstractFour rare flower‐colour mutants were detected in natural populations of Lupinus pilosus in Israel. The breeding systems and genetic bases of three oif them were examined.Mutants were tagged in wild populations and seed obtained upon open pollination was collected and grown in a, net house which was insect‐proof. Mutant progenies were used in crosses with each other and with wild‐type plants.Our results indicate the possibility that all three mutants are simple Mendelian recessives to the wild‐type deep‐violet colour and that in L. pilosus this colour is not monogenic but determined by at least two loci.All these mutants show a high degree of selling when open‐pollinated in nature.
Stomatal Density and Length for Breeding of Evergreen Azaleas (Rhododendron simsii Planch.)
Authors: Heursel J. , Ceulemans R. , Ibrahim N. 
Published: April 2006

AbstractThe hentability of stomatal density and stomatal length has been studied for four evergreen azalea (Rhododendron simsii Planch.) cultivars with the aim to evaluate the possibilities of stomatal characteristics of parental plants for increasing the crown diameter – hence yield – of the offspring., A nearly complete diallel cross with reciprocals has been carried out with the four parental cultivars. Highly significant general combining ability (GCA) values of the parents were found for stomatal length and density, but not for the crown diameter. GCA values of crown diameters did not correspond with GCA values of either stomatal length or stomatal density. Therefore it was concluded that utilizing stomatal characteristics as a selection tool for an increased crown diameter (yield) in azalea., may not be feasible.Differences in crown diameter could not be explained from correlations with either stomatal density or stomatal length.
Genetic Analysis of Resistance to Brown Planthopper in Rice (Oryza sativa L.)
Authors: Kabis Anwarul , Khush G. S. 
Published: April 2006

AbstractSeventeen rice cultivate resistant to brown planthoppers were genetically analyzed using the Bangladesh insect population. Seven cultivars were found to have a single dominant gene for resistance. These genes segregated independently of the recessive resistance gene bph‐5. Tae dominant resistance gene of ‘Swarnalata’ was designated Bph‐6. In ten cultivars, resistance is conferred by single recessive genes. In eight cultivars, the resistance genes are allelic to bph‐5. However, the recessive genes o: two cultivars are non‐allelic to bph‐5. The recessive gene of T12 is designated bph‐7.
Cytological Evidence for Fertilization in Hexaploid Wheat × Sorghum Crosses
Authors: Laurie D. A. , Bennett M. D. 
Published: April 2006

AbstractCrosses were made between the hexaploid wheat ‘Chinese Spring’ (2n = 42) and the diploid grain sorghum ‘S9B’ (2n = 20). Sixty‐nine out of 100 florets fixed 48 h after pollination contained an embryo, an endosperm, or both, a remarkably high frequency in view of the taxonomic distance spanned by the cross. Percentages of single or double fertilization ranged from 50 % to 91 % for individual spikes. The hybrid origin of the embryos was confirmed by examining zygotes from spikes fixed 25 to 27 h after pollination. Seven of the 8 zygotes in which chromosomes were sufficiently contracted to be counted contained 21 large wheat chromosomes and 10 much smaller sorghum chromosomes. The eighth contained 21 chromosomes from wheat and 20 from sorghum. Sorghum chromosomes did not appear to be attached to the spindle in zygote nietaphases and showed no evidence of movement towards the spindle poles in the single zygote anaphase found. Embryos with two or more cells invariably contained one or more micronuclei and metaphases in embryos with three or more cells contained only 21 wheat chromosomes showing that sorghum chromosomes were rapidly eliminated. Endosperm, when present, was always highly abnormal.