ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00474.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractThe resistant accession, LA1312, and the susceptible cultivar ‘Peto 343′, were crossed to develop F1, F2and BC1populations for genetic analysis of resistance in tomatoes toPhytophthora parasiticaDastur, the causal agent of Phytophthora root rot. There was no maternal effect on resistance. Generation means analysis indicated that tolerance to Phytophthora root rot was under genetic control with both simple (additive and dominance) and digenic interaction (additive × additive and additive × dominance) effects contributing to the total genetic variation among generation means. Weighted least square regression analysis indicated that the majority (ca. 96 %) of the genetic variation could be explained by simple additive effects alone. Narrow sense heritability was estimated as 0.22. Based on effective factor formulae, at least five effective factors controlled the resistance. Implications for breeding procedures are disc

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00475.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractUsing monosomic lines of wheat cultivars ‘Palur’ and ‘Compal’ as recipient parents as well as disomic substitution lines of chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’, F3‐populations and BC1′‐ to BC3′‐populations with limited and free recombination of the 20 and 21 parental chromosomes, respectively, were realized and tested in field trials in comparison to the corresponding recipient cvs. ‘Palur’ and ‘Compal’. F3‐ and BC'‐populations with the homozygous chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’ expressed higher and more stable grain protein values than the comparable populations with free recombination of the same chromosomes. The grain protein content of populations with limited recombination was significantly increased compared with the recipient cultivars. Some advantages of using intervarietal substitu

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00476.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA cultivar ofMedicago sativawas transformed withAgrobacterium tumefaciensstrain At81 binary‐vector carrying the plasmid pKan3A, with the neomycin phosphotransferase gene under the control of the mannopine biosynthesis promoter. Stem segments were infected with the bacterium and kanamycin resistant calli were obtained; plant regeneration via somatic embryogenesis and polyembryogenesis was achieved only in media devoid of the antibiotic. Genetic transformation was confirmed by the presence of the structural gene through DNA‐DNA hybridization and the enzymatic assay showed its functional expression. Mesophyll protoplasts, leaf calli and S1 progeny of transformed plants grew in the presence of kanamycin (100 μgml‐1). Results are discussed in relation to the use of kanamycin‐resistant plants in somatic hybridization in the genus

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00477.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractFifty genotypes and ten growth‐regulator combinations were used in two experiments (I and II) to investigate genotype and hormonal effects on production of callus and embryoids via anther culture in maize (Zea maysL.). Hormonal effects across all genotypes were not significant in either experiment. However, highest callus‐induction frequencies in both experiments occurred on YP basal medium plus 2,4‐D at 2.0 mg 1−1, and kinetin at 1.5 mg 1−1indicating that this combination was more effective than others. Genotypic differences in callus or embryoid induction across all media were significant. The most responsive genotypes in experiment I were single‐cross hybrids Yuanwu × 592 and K727 × K305, which produced 18.3 and 6.7 % calli, respectively, with their appropriate media. The most responsive entry in experiment II was CIMMYT Pool 29, which produced 15.0 % calli on appropriate medium and an average of 10.0 % calli across 10 media. Twenty‐three plantlets was regenerated from this study. Most of them developed

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00478.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractGenetic analysis of three semi‐dwarf genotypes of rye (Secale cerealeL.)—‘Moskowskij Karlik’, ‘Gülzow kurz’ and ‘R 18’, which were shown to be insensitive to applied gibberellic acid (GA3), has been carried out by using a seedling test. It could be demonstrated that all of the three genotypes are carrying recessive alleles for GA‐insensitivity. Whereas the alleles of ‘Moskowskij Karlik’ and ‘R 18’ seem to have the same locus on chromosome 5R, the GA‐insensitivity of ‘Gülzow kurz’ is governed by a different gene, most probably located on chromosome 7R. The relationship between the genes (alleles) for GA‐insensitivity and semi‐dwarfness, including the symbolization of theGai‐genes as well as their u

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00479.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA diallel cross of six inbred lines of maize (Zea maysL.) from the Corn Belt of the USA and one inbred line (NZ1A) with characteristics of maize from the highlands of Mexico was grown in a cool, temperate environment. The objective was to investigate interrelationships and combining abilities of plant development traits likely to influence the time required to reach low ear moistures in the field. The traits were days to silking, days to physiological maturity, ear moisture at physiological maturity, grain filling duration and ear drying rate after physiological maturity. Grain yield and grain moisture at harvest were also considered.Differences among the hybrids of this diallel cross for ear and grain moisture at the usual harvest time were largely determined by differences in ear drying rate after physiological maturity, and not by differences in days to silking, days to physiological maturity, or in ear moisture at physiological maturity. General combining ability (GCA) effects were much larger than specific combining ability (SCA) effects for all traits. NZ1A had positive GCA effects for grain filling duration and negative GCA effects for ear moisture at physiological maturity which were outside the range of the Corn Belt lines suggesting that this line, or similar Mexican germplasm, could be useful for developing hybrids with high grain yields and low ear moistures at harvest in cool, temperate environments.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00480.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractAnther culture has been demonstrated to be an applicable technique for the development of doubled haploid, i. e. homozygous lines of many crop species. In some species, androgenetic doubled haploids have already been shown to be a useful tool for breeding. However, anther culture results in sunflower have been rather unsatisfactory up to now.As in other species, anther culture response of sunflower (Helianthussp.) is strongly affected by physical, nutritional, physiological and genetical factors. By testing a number of different culture parameters, i. e. donor plant stages, culture media and conditions, and appropriate schedule could be worked out for the successful regeneration of shoots – at least for a number of sunflower lines and interspecific hybrid

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00481.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractNearly 50 percent of the 1988 advanced breeding lines of the CIMMYT bread wheat breeding program possess the 1B/1R homozygous translocation. Hence, a trial was conducted to estimate the effect of 1B/1R chromosome translocation on the yield potential of some of our high‐yielding spring wheats, where non‐limiting levels of fertility, moisture, preventive pest and disease programs were used. In conclusing the 1B/1R lines seemed to have increased their above‐ground biomass yield, number of spikes per meter2, 1000‐grain weight and test weight. They also exhibited a slight advantage over the 1B homozygous lines on grain yield. The observed difference, however, was non‐significant, as was the plant height difference observed among the two groups. Varietal comparisons indicated that the 1B/1R group headed later than the

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00482.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA technique for thein vitrocolchicine treatment of microspore‐derived haploids of rape (Brassica napusL.) is presented. This allows effective and time‐saving chromosome doubling. The most effective method consists of an application of 50 mg/1 colchicine in a liquid B5 medium to the rooted micro‐spore‐derived plantlets for 4–8 days. By this treatment more than 50 % of the plants developed at least diploid sectors. A change of medium after some days may even increase this diploidiza

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1991.tb00483.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY