摘要:

AbstractGenetical studies on mildew resistance were carried out withHordem spontaneumderived 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 theH. spontaneumderived lines, while the presence of known genes for mildew resistance (i.e,Ml‐a.9andMl‐p) was established only in two cases. Independent segregation from theMl‐alocus 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 ofH. spontaneumwere closely linked or alleles to theMl‐alocus, but shown to be different from 15 previously identifiedMl‐aalleles. It is suggested that these genes should be designatedMl‐a16, Ml‐18, Ml‐19 Ml‐20andMl‐a21respectively. No recombinants were found in test crosses when both parents carried genes/alleles of theMl‐alocus. In addition, polymorphism has been observed also for theMl‐alocus. 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 designatedMl‐iThe potential use of H. spontaneum genes for mildew re

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01181.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractFourty two barley lines direved from the F7of crosses between barley cultivars and different accessions ofHordeum spontaneumcollected in Israel and 30 lines or varieties with known genes for resistance to powdery mildew were included m this study. Eleven European and three Israeli powdery mildew cultures, possessing virulence genes corresponding to known resistance genes, were used to make comparisons between the varieties with known resistance genes andH. spontaneumderived lines. The reaction pattern of 39H. spontaneumderived lines was clearly different from the reaction pattern o; any of the known genes for mildew resistance included in this study. Only two cases were observed in which the reaction pattern ofH. spontaneumderived lines agreed with reaction patterns of known genes for mildew resistance viz.Ml‐a9andMl‐p.Trie Mildew resistance of one line apparently traces back to uncontrolled outcrossing with aMl‐a.6+Ml‐gresistant cultivar. Since the majority of the 42 host genotypes tested showed distinctive variation in resistant reaction types against different mildew cultures, this study docs not support the assumption that differences in resistant infection types against distinct mildew cultures are sufficient to indicate the presence of supplementary genes for resistance in a given genotype of the host. The results justify the conclusion that the natural population ofH. spontaneumin Israel forms a large gene pool for mildew resistance which is not yet used m cultivated

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01182.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractTwenty‐three cultivars of spring wheat were inoculated with nineteen different powdery mildew isolates; their ruction patterns hive been compared with those of twenty‐two cultivars/lines carrying identified powdery mildew resistance genes. Applying the gene‐for‐gene hypothesis, it is evident that three cultivars have none of the resistance genes used, seven others (including ‘Solo’) may carry Pm4b, only. The resistance pattern of ‘Selpek’ is identical to A/‐1 resistant cultivars of winter wheat and may be explained by the presence of Pm5. The resistance pattern ofPm5(Mt‐i) cultivars is very different from a number of ‘Kolibri’‐related cultivars of spring wheat. Since either all or nothing of that specific pattern has been transferred to all cross progenies of ‘Kolibri’, a single gene is assumed to oe responsible for it, preliminarily designated asMl‐k.The cultivar ‘Mephisto’ carries the ‘Normandie’ resistance (Pwl 2, 9). In five cultivars to spring wheat the combined effects of at least two of the above‐mentioned sources have been found. Despite the fact that ‘Normandie’ and ‘Sappo’ are not closely related. ‘Sappo’ shows the complete ‘Normandie’ resistance pattern pl

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01183.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractThis study gives estimates of breeding progress achieved in winter barley (Hordeum vulgareL.) 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/m2and seeds/spike (16 and 28 %, respectively) over the local populations. In the modern two‐rowed cultivar ‘Igri’ the increase in tillers/m2and 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 photosynt

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01184.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractWith the aim of widening the genetic variability of hexaploid tritorceum through the wheat parents, amphiploids betweenHordeum chilenseandTriticum turgidumssp.dicoccoides, ssp.georgicum, and Cody,polonicumhave been synthesized. The meiotic behaviour and the fertility were examined in these amphiploids. The morphology of the amphiploids in comparison to their wheat parents was described.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01185.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

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 cost

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01186.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractChicory has potential as a new industrial crop. However, root chicory seems to have a limited generic basis which might hamper breeding progress. The objective of the investigation was (i) TO assess the yield potential of chicory and (ii) to ascertain whether leaf chicory might be suitable to broaden the genetic basis of root chicory breeding. Forty‐nine accessions of leaf and root chicory were cultivated in field trials. Root yield/plot varied between 15.0 kg and 22.6 kg (experiment 1) and 14.8 kg and 27.0 kg (experiment 2). Total sugar content ranged between 15.2–21.8 % and 14.5–22.9 %. The corresponding values for total sugar yield are 2.32–4.12 kg and 2.38–5.45 kg. Fructose/glucose ratios ranged from 6.59 to 9.76 and 4.20 to g.22 depending on experiment and accession. Estimated on a plot oasis the highest total sugar and fructose yield was achieved by ‘Fredonia’ (10.6 t/ha and 9.5 t/ha, respectively). In addition, correlation coefficients between yield components were estimated. The correlation coefficients between total sugar content and total sugar yield ranged from, r = 0.62–0.78. The results suggest that leaf chicory may not contribute to a rapid breeding progress in root chicory within

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01187.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractEgyptian henbane,Hyoscyamus muticusL. (Sol‐anaceae) is an important source of pharmaceutically valuable compounds, the tropane alkaloids. Even today these alkaloids, scopolamine and hyoscyamine, are extracted on an industrial scale from plants. We have studied the possibilities of increasing the scopolamine content inH. muticusplants by selection during several generations. The quantitative scopolamine and hyoscyamine determinations were performed on the dry leaf material by radio and enzymeimmunoassay.The increased production of these alkaloids by the progenies was an inherited attribute resulting from systematic selection for high‐alkaloid‐containing plants (inbred). The scopolamine content in the F1generation was increased by a factor of 3 and in the F4generation by a factor of 20 compared to the P generation, respectively. The year‐to‐year fluctuation among the mean scopolamine contents of the control groups was small. The maximal scopolamine content inH. muticusstrain Cairo exceeded 4%, which is the highest content so far reported in the literature.When crossing the high and low scopolamine‐producing plants, the scopolamine content of the progenies was found to be intermediate between that of the two parents, thus indicating that scopolamine synthesis is inherited by the progenies from both parents. The alkaloid production of the plants grown in the greenhouse was significantly higher than those grown i

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01188.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractFour rare flower‐colour mutants were detected in natural populations ofLupinus pilosusin 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 inL. pilosusthis colour is not monogenic but determined by at least two loci.All these mutants show a high degree of selling when open‐pollinate

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01189.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractEmbryogenic callus cultures of barley (Hordeum vulgareL.) were frozen in the presence of a cryoprotector and subsequentjy stored in liquid nitrogen. After thawing, a high percentage of cultures resumed growth after a lag‐period of 2–4 weeks. Plant regeneration was achieved at a frequency comparable to that observed in control cultu

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01190.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY