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91.
92.
93.
连作对棉田土壤枯、黄萎病菌数量及细菌群落的影响 总被引:2,自引:1,他引:2
采用选择培养法测定新疆库尔勒不同连作年限棉田土壤枯、黄萎病病菌数量的变化,运用PCR-DGGE(Polymerase chain reaction-denatured gradient gel electrophoresis)技术分析棉花连作对土壤细菌群落结构和多样性的影响。结果表明,不同连作年限棉田的枯萎病菌和黄萎病菌量具有相似的变化特征,即在5~20年连作年限内,土壤中病原菌量随着连作年限的延长而增加,20年连作土壤病原菌数量达到最高峰;连作超过20年,土壤菌源数量开始下降。不同连作年限棉田土壤中枯、黄萎病病原菌的数量与发病株率呈显著正相关关系。连作棉田土壤细菌群落的DGGE图谱分析显示,连作棉田土壤细菌种群的组成、结构、丰富度均发生变化。连作5~40年的棉田土壤细菌种群Shannon-Wiener多样性指数(H')、均匀度(EH′)和丰富度(S)指数均降低,且连作年限越长降低越突出。 相似文献
94.
Arachis glabrata Benth, variety glabrata collector GK 10596 (PI276233; ICG 8176) belonging to section Rhizomatosae has resistance to rust, late leaf spot and viral diseases. A. hypogaea L. cv MK 374 (section Arachis) is susceptible to rust, late leaf spot and to the viral diseases peanut stripe, peanut mottle and peanut bud necrosis. Hybrids
between A. hypogaea cv MK 374 and A. glabrata were produced after inter specific pollinations and embryo culture. The hybrids produced had morphological characters of
both parents plus floral abnormalities not seen in either parent. It was possible to identify the hybrids by esterase isozyme
analysis when still in culture. Cytological research showed variable chromosome association and also homeology between the
genomes of A. hypogaea and A. glabrata. The hybrids inherited resistance to rust, late leaf spot, peanut bud necrosis and peanut stripe diseases from the pollen
parent A. glabrata.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
95.
An electrophoretic study of gliadin and glutenin proteins, mainly low-molecular-weight (LMW) Glutenin Subunits, was undertaken to investigate possible assoeiations between these proteins and gluten strength. Thirty-eight durum wheat cultivars having different origins and currently grown in Spam were analysed. Different electrophoretic methods were used to analyse the seed storage proteins. Protein grain content was estimated and gluten strength was measured by the SDS-sedimentation test. New patterns for LMW glutenins were observed. Besides the known patterns of LMW-1, associated with γ-gliadin 42, and LMW-2 associated with γ-gliadin 45, six cultivars had LMW-2? associated with γ-gliadin 43, one cultivar showed LMW-2* associated with γ-gliadin 44, and another cultivar, null for γ-42 and γ-45, had LMW-1?. Significant differences for gluten strength were found among groups of cultivars with different LMW patterns. High molecular weight glutenins were found in general to be poor indicators of viscoelastic properties, although band 20 showed a negative influence on quality. The results are discussed in relation to development ol cultivars with good gluten strength. 相似文献
96.
Karyotypic and electrophoretic studies on taro and its origin 总被引:4,自引:0,他引:4
Summary Karyotypes and electrophoretic pattern of 15 strains of taro were studied. Strains collected from the northeast India hill state, Meghalaya were diploids and triploids whereas those from the plains of south India were diploids and of north India was a triploid. The diploids had 2n=28 and triploids showed 2n=42 chromosomes. The wild taro had the most asymmetrical karyotype. The protein content varied from 4.2 to 11.4 mg/g dry wt. The maximum protein content was found in a triploid strain 8 (11.4 mg/g dry wt) and minimum in the wild taro (4.2 mg/g dry wt). The number of protein bands was 7 in the wild taro (diploid) and 12 in one of the cultivated triploid strain. Meghalaya strains showed great variation with respect to leaf size and tuber shape and size. All the strains have diverged at morphological, karyotypic and genotypic levels. It is suggested that taro might have originated in the north-eastern India. 相似文献
97.
Summary Electrophoretic variants of peroxidase in mulberry (Morus spp.) were demonstrated by thin-layer gel isoelectric focusing. Of these variants, three isozyme band groups were found to be controlled by codominant alleles at a single locus. The gene symbol Px
1 was given to this locus, with alleles Px
1
1 and Px
1
2 assigned to the A6-A7-A8 and A7-A8-A9 band groups, respectively. The A6-A7-A8-A9 band group proved to be controlled by the Px
1
1 and Px
1
2 heterozygote.Additional experiments showed that among the three banding types, there were no statistically significant differences in leaf blade length, leaf blade width, length-width ratio of leaf blade, internode length, phyllotaxis, leaf shape, tree vigor and resistance to powdery mildew, but there were significant differences in leafstalk length. 相似文献
98.
Lucia Lioi 《Euphytica》1989,44(1-2):151-155
Summary Variation of phaseolin, the major storage protein in Phaseolus vulgaris L., was analysed in seeds of a germplasm collection from the Mediterranean area. Results showed a number of subvariants differing from the reference patterns for the presence, absence or faintness of single polypeptides. Maximum concentration of variation was found in the Cyprus material. Sources and causes of variation are discussed. 相似文献
99.
Disomic wheat-barley addition lines carrying a full hexaploid set of chromosomes of the wheat cultivar Chinese Spring, plus a pair of either chromosome 1, 2, 3, 4, 6, or 7 from the barley cultivar Betzes, were assayed electrophoretically. Comparisons of zymograms of each addition line with the Chinese Spring wheat and Betzes barky parents of the addition lines gave direct (presumptive in the case of chromosome 5) evidence of the chromosomal locations of nine enzyme loci which have been useful genetic markers in studies of the population genetics, ecogeneties and breeding of barley. Previously reported chromosome locations of several loci were confirmed and evidence was presented for the existence and probable chromosome locations for additional enzyme loci. 相似文献
100.
Variability of high molecular weight glutenin subunits (HMW-GS) was studied in198 accessions of Ae. Tauschii (2n=2x=14, DD) by sodium dodecyl sulphate(SDS-PAGE) and acid polyacrylamide gel electrophoresis (A-PAGE) and capillary electrophoresis
(CE). A high allelic variation of HMW-GS, including some novel x- and y-type subunits and variable subunit combinations were
observed. One accession(TD159) showed a x-type null form. The results by A-PAGE analysis revealed that the subunits Dx5
t and Dy10
t encoded by Glu-D
t
1 locus in Ae. tauschii were different in relative mobilities in comparison with the subunits Dx5 and Dy10 found in bread wheats, whereas they had
the same mobilities, respectively, when separated by SDS-PAGE. The higher resolution of Ae. tauschii HMW-GS separated by CE method showed two clear peaks in accordance with x- and y-type subunits, respectively,except the accession
TD151 which possessed only subunit Dy12.1*t. The electro elution time of the x-type and y-type subunits were about 13–14 and 7–8minutes, respectively. Characterization
of wheat HMW-GS was facilitated by using CE which provides high resolution and increases the speed of analysis in conjunction
with the traditional gel electrophoretic methods. A total of 42HMW-GS alleles were identified, among which were several alleles
not presently detected in bread wheats. Hence Ae. tauschii is potentially a valuable genetic resource for quality improvement of bread wheat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献