摘要:

AbstractAttempts at interspecific hybridization were made betweenPhaseolus vulgaris(common bean) andP. acutifolius(tepary bean) using a new pollination method and embryo rescue. The success of interspecific hybridization depended upon the pollination technique, the species and individual genotypes used as female and male parents, and the growth conditions. A high hybridization efficiency was achieved whenP. vulgariswas used as female parent. When pods were left on the maternal plants hybrid seeds were obtained which developed into abnormal seedlings. These died at an early stage of growth. Hybrid plants were grown to maturity following embryo rescue, but all showed different developmental abnormalities. The growth of these was determinate like the female parent,P. vulgaris, but leaf morphology was closer to the male parent,P. acutifolius.The utilization ofP. acutifoliusgermplasm for the improvement of common bean remains limited, and further studies are needed to develop promising embryo rescue protocols in such wide crossing programmes.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00285.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractFrom two tetraploid, one Transformed tetraploid, one triploid and 11 dihaploid clones ofSolanum tuberosumsomatic hybrids were produced by polyethylene glycol mediated somatic fusion. The inter‐dihaploid clones comprised clones of agronomic value, homozygous doubled monohaploids, andin vitroselected clones resistant t0Fusarium or Phytophthoratoxins. Presumptive hybrids were enriched at the callus Stagein vitroby using differentiating media and by growth characteristics; further identification was performed by chromosome countingin vitroshoots and by isozyme analysis of in vitro plants. Final analysis was made from morphological characteristic of plant and tuber phenotypes. From 15 different combinations, 6009 plantlets have been regenerated. From five combinations, 310 reentrants were checked for hybrid nature by morphology and cytology and 88 by peroxidase and esterase isozyme analyses. Amongst these, from two combinations, a total of 17 different hybrids were confirmed by all methods. The procedures described are general enough to allow genome combination of interdihaploids resulting in tetraploids of practical breeding valu

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00286.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractSeeds of linseed (Linum usitatissimumL.) cultivars ‘Raulinus’ and ‘Bionda’ were treated mutagenically with ethyl methanesulfonate (EMS) in order to broaden the variation of fatty acid composition in the seed oil and to select mutants with reduced linolenic acid (C18: 3) content. The M2generation was evaluated for fatty acid composition of the oil. Genetic variation for unsaturated fatty acids was demonstrated to be extended in the M2generation as compared to the controls. Finally in the M5generation of cv. ‘Raulinus’, lines with reduced C18:3 (<40% vs. 55%) and correspondingly increased linoleic or oleic acid contents, respectively, could be selected. These mutants proved to be genetically stable as demonstrated by parent‐offspring (M4/M

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00287.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractHandcrosses were made in a factorial manner with 24Vicia fabainbred lines m three sets, each between four male and four female parents. The resulting 48 hybrids, their parental inbreds and three commercial varieties were grown in performance trials during the years 1985—87 with three replications at one location. Yield and yield components were recorded on single plant basis.The average superiority of the hybrids above the control varieties was 26 % in plant yield. The best crosses outyielded the controls by more than 50 %. However, a few inbred lines also reached, the yield level of the controls.The average heterosis was significant for all characters except for maturity date. In plant yield the average heterosis was 75%, ranging between 34% and 148% in the various cross combinations. The highest average heterosis of 110 % was observed in yield at the lateral stems. In all characters the best inbreds were superior to the lower hybrids and in some characters even equal to the average of the hybrids.A strong positive relationship was found for all characters between hybrid performance and mid‐parent value and between the per se performance of the inbreds and their general combining ability.Genotypic differences between the hybrids as well as between the inbreds were highly significant. Most of the variability between the hybrids in all characters were attributed to general combining, ability with only little evidence for specific combining ability.In the discussion the results are evaluated according to the choice of the breeding category of the partial allogamous faba bean spec

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00288.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThree pot experiments were earned our to investigate the variation among geographic accessions ofOrobanche crenataForsk. in their ability to attack different stocks ofVicia fabaL.Orobancheaccessions were quite different in their influence on the performance of genetic lines of the host. However, host parasite relationships appeared to be dependent upon environmental conditions. The usefulness or host genotypes for differentiating between parasite accessions was rather limited. The number ofOrobancheshoots per host plant does not appear 10 be a precise indicator of host tolerance although it has been frequently used for this purpose.

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00289.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractSelection of superior host genotypes in symbiosis with nativeBradyrhizobiumhas been suggested as a means of increasing nitrogen fixation m peanut (Arachis hypogaeaL.). In this study progeny from a cross of cultivars ‘Florigiant’ and ‘Florunner’ inter‐mated twice and selected for yield formed the base population. The 44 selected S2,1families, ‘Florigiant’ and ‘Florunner’ were evaluated at two sampling dates at each of two locations for traits indicative of nitrogen fixation. Five families were selected in each of four selection groups — high and low acetylene reduction and high and low plant weight. Selected families were retested in a second year and inter‐mated. S2,1progeny within each selection group were bulked and evaluated for nitrogen‐if using characteristics at two ‘sampling dates at two locations. After intermating, the mean of the high acetylene reduction group, 62.9 μ/moles C2H4/plant hr, was Significantly greater than the mean of the low acetylene reduction group, 52.5 μmoles C2H4/plant/hr, and of the mid‐parent, 55.8 μ/moles C2H4/plant/hr. The associated estimate of realised heritability was 55 ± 08 indicating the response to selection was approximately halt the selection differential and that the distinction between families selected for high and low acetylene redaction was maintained after intermating. However, the realized heritability estimate obtained from the means of the base population and the selected families inbred one generation was .14 ± .06 indicating a failure to maintain distinct groups after one generation of inbreeding. The utility of early generation selection for enhanced N: fixation is, therefore, doubtful in this population.Selection based on plant weight was not effective. A significant difference in the plant weight means of the high and low plant weight groups was not detected when selections were retested or after inter‐mating. Plant weight was not a useful indirect selection

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00290.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractChickpea (Cicer arietinumL.) is an important legume crop in India. The present study was conducted to investigate the inheritance of several developmental traits in three crosses of chickpea, viz., WFWG III’בT20’, ‘T88’בBold Seeded’, and ‘NP34’בP1528‐1‐1’, each having seven generations. The seven generations were P1, P2, F1, B1, B2, F2, and F3. The experimental lay‐out was randomized complete block design with three replications. Data were acquired on days to flowering (DF), days to maturity (DM), plant height in cm (PH), number of primary branches (PB), and number of secondary branches (SB). Generation mean analysis was used to estimate the genetic components; narrow sense heritability was estimated using variance components; and correlation analysis to estimate correlation coefficients among different traits. Genetic differences were found in all three crosses for all traits studied. Additive, dominance, and epistatic effects were found for many traits'. Duplicate epistasis was observed for all traits except number of PB. Higher order interactions and/or linkage were detected for DM and SB. For many traits the relative magnitudes of the genetic effects differed among crosses, thus the extrapolation to other crosses may be difficult. The inheritance becomes more complex as the fate of the character is decided at a later stage in the life cycle. Positive heterosis was observed for some traits, but the exploitation of this component may not Feasible since stable male sterile lines are not available. Early maturity and high yield ‘may be selected independently because of the absence of any significant corr

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00291.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractPresent state of hybrid wheat breeding in the GDRThe possibility of developing economically efficient hybrid wheat is demonstrated by own experimental results. Male sterile analogues, based onT. timopheevi, with a satisfactory level of yield and sufficient sterility were produced. Restores were obtained by combining analogues and use of the pedigree method which resulted in strains with complete restoration and high grain yield. Hybrid seed yields approaching 70% of normal wheat yields were obtained on 1‐ and 3‐m ms strips with a ms: Rf ratio of 1: 1.5—2.5The yields of the best hybrids in a tweleve‐location trial rose from 98% compared to the standard variety ‘Alcedo’ (5.8t/ha) in 1975—1980 to 109% (7.24t/ha) in 1981—1985. In 10‐ and 30‐ha fields, yields were 122% and 110% of those recorded in the reference variety. Better results are expected form the use of new restorers and genetically divergent ms‐forms and will probably be accomplished through inte

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00292.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThe breeding materials used in this study were the F3, F4and F5‐generations of the cross between Giza 158 × Sonora 64 (Triticum aestivumL.). The objective of this study was to compare the relative merits of Smith‐Hazel, desired gain selection indices, independent culling levels and single trait selection in improving grain yield, heading date and several agronomic traits. Highly significant differences among F3families and a satisfactory genotypic coefficient of variability were obtained for all the traits studied. The genotypic correlations were high between yield and each of spike weight, kernels/spike and spikes; plant, intermediate with 1000 kernel weight and very low with heading date, plant height and spike1 length‐After two cycles of selection, the results of the gains realized indicated that the most effective method for improving yield was the Smith‐Hazel index (SH7) of seven traits followed by the desired gain index of seven traits (DG7), SH5, independent culling levels, DG5and direct selection (or grain yield/plant. Direct selection for heading date, plant height and spike length was the best method for improving these traits, but undesirable correlated responses in the other traits were

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00293.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractRye‐cytoplasmic rye‐wheat‐additions were produced by double backcrossing rye‐cytoplasmic tetraploid triticale with an inbred line of diploid rye cv. ‘Esto’. Addition 6B was identified using L

ISSN:0179-9541    

DOI:10.1111/j.1439-0523.1988.tb00294.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY