摘要:

AbstractInvestigations were carried out to assess the suitability of the intergeneric crossHordeum vulgare×Psathyrostachys fragilisfor haploid barley production.H. vulgarecvs. ‘Emir’ and ‘Vada’ were each pollinated withP. fragilisP.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. fragileremained hybrid. Several of these flowered but there was little pairing between the parental chromosomes. Most of the plants from ‘Emir’×P. fragilisdied, as seedlings but 3 plants developed into haploid barley. Because of the practical limitations of pollen availability fromP. fragilisand the inconsistencies in haploid plant formation, it is unlikely that the cross will prove as valuable as that betweenH. vulgare×H. bulbosumfor a doubl

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01169.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractIn a screening experiment with 215 different winter cultivars ofTriticum aestivumL. 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.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01170.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractOvule and pollen fertility have been studied in doubled haploids of cocoa derived from spontaneous haploids, doubled by colchicine treatment. The two measures of fertility were very variable; occasionally, the levels were as high as those of the parent plant, but most were lower. The low fertility was not improved either by changing pollinators or after grafting. Pollen fertility also varied seasonally more in doubled haploids than in their parents.The lack of differentiation of embryo sacs seemed to be the cause of low values of ovule fertility. Both of these unfavourable characteristics were not observed in the progeny of doubled haploids, The low fertility is described in terms of homozygote depression, forced, on normally allogamous plants, its consequences for the use of doubled haploids in the production of hybrid seeds are discussed.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01171.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

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 bea propostheir characters directly involved in seed production. These selected doubled haploids will subsequently have to be tested as progenit

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01172.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractIn vitroculture of shoot apical meristems ofHelianthus annuuswas 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. Duringin vitroplant development, a diplontic selection took place that was more rapid when very precociousin vitroflowering occurred.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01173.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractThe performance of single cross hybrids between resynthesized (resyn.) genotypes and varieties of rapeseed was tested in microplots. The results revealed strong, genetic differences between the artificially synthesized rapeseed forms for all the characters investigated, as well as for g.c.a. values. In particular, hybrids with resyn rapeseed exhibited a vigorous vegetative growth. It should therefore, be beneficial to use resyn forms directly in fodder rape breeding programmes.Disturbances in fertility of the resyn material resulted in a low number of seeds per pod and consequently in an inferior seed yield as compared to the varieties, although some high yielding combinations were also identified. Three‐way hybrids with a 25% genome share of the resyn rapessed reached only lower vegetative performance as compared 10 the hybrids with a 50% resyn genome but their performance in generative traits was general superior‐ In respect to seed yield some progenies of three‐way hybrids showed a higher plot performance than even the high yielding varieties. A further comparison between single‐cross combinations of resyn × variety on the one hand and variety × variety on the other hand demonstrated that resyn genotypes, due to a distinct apical dominance, exhibited a pronounced expression of characters measured on the main stem. But in total, ii is evident from the present findings that any hybridization with this resyn material does not promise immediate short‐term varietal

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01174.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractMultiple endopeptidases as biochemical marker for resistance of winter wheat toPseudocercosporella 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 toPseudocercosporella 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 toP. herpotrichoides.A close relationship between the absence of EP‐1 and the introduction ofAegilops ventricosaresistance is assumed. The use of this biochemical marker in wheat breeding

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01175.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

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. aestivumandT. 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 resp

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01176.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

AbstractThe estimation of combining abilities and heterosis for quantitative resistance againstErysiphe graminisf. sp.hordeiof eight spring barley (Hordeum vulgare) cultivars is presented. Fur this purpose a half diallel cross and its parents were arranged in five Latin rectangles, each inoculated with a current mildew isolate. Significant general combining ability was found whereas specific combining ability was non‐significant. A great pan of the general combining ability could be explained by variety effects. Significant variety heterosis was obtained too. Significant average heterosis was obtained but us effect was small. Among those selected for this study, ‘Grit’ and ‘Hora’ were the best parents for furthe

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01177.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

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 mixture

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1987.tb01178.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY