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1.
玉米大斑病菌HT—毒素与玉米细胞的膜脂过氧化研究 总被引:7,自引:0,他引:7
以土培玉米幼苗为材料,通过测定玉米大斑病菌HT-毒素处理后玉米叶片细胞膜透性和细胞内丙二醛(MDA)含量变化及其与细胞内过氧化物歧化酶(SOD)、过氧化物酶(POD)活性之间的关系来研究玉米细胞膜脂过氧化的程度。结果表明,HT-毒素胁迫后,亲和组合MDA含量上升,POD活性受到刺激,SOD活性受抑制较强;非亲和组合POD活性受到抑制,SOD活性受抑制较弱。HT-毒素对玉米叶片细胞膜有强烈的破坏作用,而且这种作用与毒素的浓度和毒素处理的时间呈正相关。试验结果初步推测在抗、感玉米的细胞膜上可能都有HT-毒素的结合位点,但毒素作用后幅地它们的活性氧代谢程度不同而导致了对HT-毒素敏感性的差异。 相似文献
2.
濒危植物——长喙毛茛泽泻的雌雄配子体发育 总被引:2,自引:0,他引:2
长喙毛茛泽泻 Ranalisma rostratum stapf 小孢子母细胞的减数分裂过程为连续型,四分体为左右对称型。成熟花粉为三胞花粉。花药绒毡层为变形绒毡层。雌蕊由多数单室子房构成,每子房中含一具双珠被、薄珠心的倒生胚珠。胚囊发育为葱型。成熟胚囊中三个反足细胞退化;二个极核分别位于中央细胞的两端,其体积相差明显。这种极核分布可能与反足细胞过早退化有关。 相似文献
3.
Fungi isolated from soil in Timna Park (Israel) were found to belong to a new species of Exserohilum for which the name Exserohilum israeli sp. nov. is proposed. The main physiological properties of members of this species are discussed and the influence of temperature and copper concentrations on the growth and morphology of the fungus were investigated. 相似文献
4.
H. G. Welz A. W. Schechert H. H. Geiger 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):1036-1045
Cultivars with quantitative resistance are widely used to control Setosphaeria turcica (Luttrell) Leonard & Suggs, the causal organism of northern corn leaf blight (NCLB). Here the effectiveness of quantitative
trait loci (QTLs) for NCLB resistance was investigated over the course of host plant development in inoculated field trials.
A population of 194–256 F2:3 lines derived from a cross between a susceptible Italian (Lo951) and a highly resistant African inbred line (CML202) was
tested in three environments in Kenya. The traits assessed were the incubation period (IP), the percentage disease severity
(DS 1 to 5, taken biweekly), and the area under the disease progress curve (AUDPC). Considering all resistance traits and
environments, a total of 19 putative QTLs were detected by composite interval mapping using a linkage map with 110 RFLP markers.
In the combined analysis across environments, nine QTLs were significant (LOD >3.0) for DS 3, recorded around flowering time,
explaining 71% of the genotypic variance. Four of these nine QTLs displayed significant (P<0.05) QTL×environment (QTL×E) interaction. Most QTLs were already significant in the juvenile stage (IP) and became less
effective after flowering. Across environments, three QTLs conditioned adult-plant resistance, in the sense that they were
only significant after flowering. Six QTL alleles on chromosomes 2, 4, 5, 8, and 9 of CML202 should be useful for marker-assisted
backcrossing.
Received: 24 August 1998 / Accepted: 29 September 1998 相似文献
5.
H. G. Welz X. C. Xia P. Bassetti A. E. Melchinger T. Lübberstedt 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(3-4):649-655
Quantitative trait loci (QTLs) for resistance to the fungal pathogen Setosphaeria turcica, the cause of northern corn leaf blight (NCLB), were mapped in a population of 220 F3 families derived from a cross between two moderately resistant European inbred lines, D32 (dent) and D145 (flint). The population
was genotyped with 87 RFLP and 7 SSR markers. Trials were conducted in the field in Switzerland, and in the greenhouse with
selected F3 families in Germany. The F3 population segregated widely for resistance with transgression of the parents. By composite interval mapping, a total of
13 QTLs were detected with two disease ratings (0 and 3 weeks after flowering). Together these QTLs explained 48% and 62%
of the phenotypic variation. Gene action at most QTLs was partially dominant. Eight out of the 13 QTL alleles for resistance
were contributed by the more-resistant parent, D145. On chromosomes 3, 5 and 8, QTLs were located in the same chromosomal
regions as QTLs in tropical and U.S. Corn Belt germplasm. Some QTLs affected NCLB, head smut and common rust at the same time,
with alleles at these loci acting isodirectionally.
Received: 25 January 1999 / Accepted: 20 Februar 1999 相似文献
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7.
在调查研究中国东部暖温带地区土壤中暗色丝孢菌过程中,采用稀释平板法和土壤颗粒平板法分离获得100余株蠕形菌的分离物。经纯化培养后,依据形态特征鉴定为3属21种,其中虎尾草平脐蠕孢[Bipolaris chlorides (Alcon) Alcon]和小柄凸脐蠕孢[Exserohilum pedicellatum (Henry) Leonard & Suggs]为中国新记录种。文中列出了各蠕形菌的种名、采集地、土样号以及菌株号,对2个新记录种进行了详细描述。所有活菌株及干制培养物保存在山东农业大学植物病理系标本室(HSAUP)。 相似文献
8.
本文报道了原白头翁素衍生物5-溴甲基-2(5n)-呋喃酮的合成和抗癌活性及其抑制农作物病原菌活性的探讨结果,表明在5~20μg/mL范围内,5-溴甲基-2(5H)-呋喃酮对人肺癌A549细胞株有明显的抑制生长的作用;在50~200μg/mL范围内,其对玉米大斑病菌等的生长抑制率可达到95%以上. 相似文献
9.
玉米大斑病抗性遗传的研究进展 总被引:26,自引:1,他引:25
由于大斑病生理小种的变异,致使原来抗大斑病的玉米品种丧失抗性,对玉米生产造成严重危害,至今已经发现大斑病菌生理小种5个。玉米对大斑病的抗性可分为多基因控制的数量性状和显性单基因控制的质量性状,前者涉及玉米的10条染色体;后者包括t1、Ht2、Ht3、HtN等基因。本文对大斑病生理小种变化,玉米大斑病抗性单基因(Ht)的来源、遗传特点、染色体定位以及数量抗性基因的QTL分析等研究进展作了综述。
Abstract:As the rapid variation and mutation of the races of Exserohilum turcicum (Helminthosporium turcicum),maize varieties lost their resistance to northern corn leaf blight (NCLB) disease caused by new races of E.Turcicum.This brought the disaster in maize production.Up to now 5 races have been found.The maize resistance to E.turcicum can be divided into quantitative and qualitative resistance,the former is associated with 10 chromosomes in maize,and the later includes genes of t1、Ht2、Ht3 and HtN.The race variation of E.turcicum,the original gene resources and genetic characteristics of each Ht monogenic resistance,the chromosome location of t1、Ht2、HtN genes,and the QTL analysis of quantitative resistant genes for E.turcicum in maize were reviewed in this paper. 相似文献
10.
Ranalisma rostratum Stapf is a rare and endangered species. This paper deals with the development of its male and female gametophytes and probes the relationship between the process of reproduction and the cause which made this species endangered. The meiosis of microspore mother cells is successive cytokinesis and the microspore tetrads are isobilateral. Pollen grains are 3-celled when shed. The ovule is anatropous,bitegmic and tenuinucellate. The micropylar dyad cell usually desenerates soon after its formation, and the chalazal dyad cell develops into a Allium type embryo sac. During the development of embryo sac both polar nuclei are respectively located at the two ends of central cell,and they maintain this situation until the micropylar polar nucleus takes part in fertilization. Features of the embryo sac of Ranalisma rostratum Stapf are discussed. 相似文献