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81.
Summary Methods developed to identify genetically diverse varieties of beans (Phaseolus vulgaris L.) were applied to closely related lines that were difficult to distinguish on the basis of seed morphology. Seedling tissues and seeds of black beans, were examined electrophoretically for isoenzyme and cotyledon proteinn protein patterns. Seven enzymes, extracted from seeds or from seedling stem, root or leaf tissues, were compared for polymorphism. Peptidase, polyphenol oxidase, phosphoglucoisomerase and glutamate oxaloacetate transaminase patterns were the same for all lines. Some differences were observed for acid phosphatase, peroxidase and esterase patterns, but complete discrimination of the six selected lines was not possible on the basis of isoenzyme patterns alone. Using polyacrylamide gel electrophoresis (PAGE) of dissociated 0.1 M acetic acid soluble proteins at pH 3.1 (acid-PAGE), or sodium dodecyl sulphate PAGE (SDS-PAGE) of residual protein extracts, all but one pair of samples in each case could be distinguished from the other samples. Using both techniques all of the lines could be identified unequivocally. 相似文献
82.
绿肥还田对双季稻根际土壤产甲烷古菌群落结构的影响 总被引:4,自引:0,他引:4
利用PCR-DGGE技术及克隆文库构建方法研究,尿素、紫云英鲜草翻压还田、黑麦草鲜草翻压还田和不施氮肥4种处理对双季稻不同生育时期(早稻季:分蘖期,拔节期,成熟期;晚稻季:分蘖期,扬花期,成熟期)稻田根际土壤中产甲烷群落结构的影响。结果表明,双季稻不同取样时期和各处理中产甲烷古菌群落结构稳定且相似,早稻季和晚稻季的优势群落均为甲烷微菌目(Methanomicrobiales)、Rice Cluster I(RC-I)、甲烷鬃菌科(Methanosaetaceae)、甲烷杆菌属(Methanobacterium),但早稻季产甲烷古菌群落的Shannon-Weiner指数(H)和丰富度指数(R)整体低于晚稻季。紫云英和黑麦草鲜草翻压还田处理较尿素处理更为明显地提高了双季稻(一年)稻田根际土壤中产甲烷古菌群落的Shannon-Weiner指数和丰富度指数,但均暂未对产甲烷群落结构产生决定性影响。 相似文献
83.
A. R. McElroy 《Euphytica》1991,57(2):117-123
Summary A breeding program aimed at improving the seed yield in bean for processing was started. Six parents divergent in a range of agronomical characters were crossed according to diallel mating design. Cluster analysis performed on the composite cross population evidenced divergence between F1 hybrids and to maximize genetic recombination, the most different F1 hybrids were intercrossed. A Factor analysis was performed on 7 morphological and yield-determining traits of 15 hybrids F1 and parents. Three Factors, representing patterns of variables interpreted as productivity per plant, growth factor, and branching-productivity, were extracted. These results evidenced the inverse relationship between seed yield components (seeds/pod, pods/plant, and hundred seed weight): i.e. the selection for either variable is detrimental to the other. It may be possible to break this association if the plant construct assures high sink to satisfy all plant requirements: tall and large plants bearing numerous nodes, leaves and reproductive structures. Moreover, the selection practiced simultaneously on the yield components positively affected the seed yield trait. An index of selection and response to selection were estimated on the segregant populations. The realized gain in seed/yield reached after one cycle of selection (C1) was 6.5 g, about 20% over the base population (C0). The expected gain from selection based on the superior 5% plants in C2 families was 25.5% and approached the realized gain. The result of this paper gives evidence to support that the seed yield can be improved by an adequate selection intensity and selection index can be very useful when it is faced with the improvement of several traits at the same time. 相似文献
84.
Summary The genetics of resistance to bean golden mosaic virus (BGMV) was studied in an 8×8 complete diallel cross of common bean, Phaseolus vulgaris L. The 28F1 hybrids, their reciprocals, and eight parents were artificially inoculated with BGMV under glasshouse conditions. Data were recorded and analyzed for foliar yellowing, plant dwarfing, flower abortion, and pod formation, using a randomized complete block design with two replications.General combining ability (GCA) mean squares were highly significant (P<0.01) and larger than values for specific combining ability for all traits. Reciprocal and maternal effects were nonsignificant. Cultivars Royal Red and Alubia Cerrillos possessed significant negative and positive GCA for all traits, respectively. Porrillo Sintetico also had negative GCA for all traits except plant dwarfing. None of the GCA effects were significant for Great Northern 31 and PVA 1111. Positive associations existed among all traits studied. 相似文献
85.
Summary Significant advances in increasing tolerance to the leafhopper Empoasca kraemeri Ross & Moore in common bean have been obtained using a new breeding scheme where yield under leafhopper attack is the principal selection criterion in the evaluation of progenies. However, to further refine this breeding scheme, a study was conducted to determine whether selection for nonprotected yield would be more effective in early versus late generations. Two selection strategies were compared. In Strategy I, early generation selections in the F2 and F3 were compared to Strategy II where late generation selections were made in the F4 and F5, with the F2 and F3 generations advanced using single pod descent and bulk practices, respectively. Yield trials of the F6 lines from both selection strategies were conducted under nonprotected and insecticide protected treatments. No significant differences were detected between the two selection strategies. However, Strategy II did produce advanced lines with greater nonprotected yields than did Strategy I, with the best F6 line, in three out of four crosses, coming out of Strategy II. Late generation selection is recommended over early generation selection. Results of the new leafhopper breeding scheme, based on yield, are compared to the old breeding scheme where selections were made using visual selection practices in early generations. 相似文献
86.
Characterisation and origin of rust and powdery mildew resistance genes in VPM1 wheat 总被引:3,自引:0,他引:3
Summary The expression of rust resistances conferred by closely linked genes derived from VPM1 varied with environmental conditions and with genetic backgrounds. Under low light and low temperature conditions seedlings carrying Yr17 showed susceptible responses. Stem rust and leaf rust resistance genes Sr38 and Lr37 tended to confer more resistance at 17±2° C than at normal temperatures above > 20° C. These studies supported the hypothesis that Yr17, Lr37 and Sr38 were derived from Aegilops ventricosa, whereas Pm4b was probably derived from T. persicum. Studies on certain addition lines and parental stocks indicated that wheat cytoplasm may enhance the expression of Sr38. 相似文献
87.
In this study, we report the use of ISSR to assess genetic diversity and to determine the relationships among ten cultivars
of common bean developed in Argentina and three materials from France. ISSR markers resolved two major groups corresponding
to the Andean and Mesoamerican gene pools of common bean. We compared the results of previous analysis, performed with RAPD
markers (Galván et al., 2001), with the results generated by means of ISSR. It appears that ISSR are better tools than RAPDs
to identify beans by gene pool of origin though they did not revealed as many differences between individuals as RAPDs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
88.
Limited but specific variations of seed storage proteins in Japanese common wheat (Triticum aestivum L.) 总被引:2,自引:0,他引:2
The electrophoretic banding patterns ofgliadin in common wheat lines derived fromJapan were determined byacid-polyacrylamide gel electrophoresis. For the 107 wheat lines used in our study,27 different patterns were identified, 13corresponding to the -gliadin, 8 tothe , -gliadin and 6 to the-gliadin. The gliadin patterns ofJapanese wheat cultivars and landracesgreatly differed from the patterns of wheatlines from other countries, and thevariation seen in wheat lines from Japanwas limited to 46 patterns. Sevencollection or breeding areas in Japanshowed different frequencies in theirgliadin patterns. Combining the gliadinpatterns with high molecular weightglutenin subunit compositions, 67combinations were observed. One gliadinpattern consisting of -gliadinpattern F, , -gliadinpattern H and -gliadin pattern Dwas frequently found in many Japanese wheatlines, though the other patterns werelimited to only one or two wheat lines. 相似文献
89.
Frew Mekbib 《Euphytica》2003,130(2):147-153
An experiment was undertaken to determine the stability of seed yield in 21 common bean genotypes representing three growth
habits. Seven genotypes in each growth habit (determinate bush, indeterminate bush and indeterminate prostrate) were evaluated
in replicated trials at three locations for three years under rain fed conditions in Ethiopia. A combined analysis of variance,
stability statistics and rank correlations among stability statistics and yield-stability statistic were determined. The genotypes
differed significantly for seed yield and genotype × environment (year by location) interaction (GE). The different stability
statistics namely Type1, Type 2 and Type 3 measured the different aspects of stability. This was substantiated by rank correlation
coefficient. There were strong rank correlations among Si
2d, Wi
2,σi
2 and Si
2, where as there was weak correlation between biand Ri
2, Si
2d, Wi
2, σi
2 and Si
2. R2 was significantly and negatively correlated with Wi
2, σi
2 and Si
2. σi
2 is significantly correlated with Wi
2.Yield is significantly correlated with bi and Ri
2.None of the statistics per se was useful for selecting high yielding and stable genotypes except the YS(yield-stability statistic). Most of the high yielding
genotypes were relatively stable. Of the 21 genotypes, only 11genotypes were selected for their high yielding and stable performance.
Genotypes with growth habit III and I (in determinate prostrate and determinate bush) were generally more stable than in determinate
bush.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
90.
Summary A knowledge of the biological and functional relationships among traits would be of benefit to plant breeders in the choice of traits to use for increasing efficiency of selection in a breeding program. Principal factor analysis was used to identify biological and functional relationships among dry bean (Phaseolus vulgaris L.) traits in segregating populations of a phenotypic recurrent selection program designed to introduce upright architecture into medium-sized dry bean.Two biological interpretations were assigned to factors extracted in the analysis of four seed/pod traits. The first was a size factor, loaded with seed weight and pod width, and the second a number factor, which was loaded with number of seeds per pod and pod length. Similarly, three factors were extracted from the analysis of fifteen architectural traits. The first factor was interpreted as an elongation factor, and was loaded with internode length measurements, while the second factor was interpreted as a structural factor, and was further divided into two subclasses namely, sturdiness factor and profile factor. The sturdiness factor comprised hypocotyl diameter and hypocotyl length, while the profile factor comprised branch angle and number of basal branches. The third factor which was called a reproductive factor was loaded with pod distribution traits and the number and location of nodes on which pods were borne. 相似文献