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61.
The wheat cultivar Kariega expresses complete adult plant resistance against stripe rust, whereas cv. Avocet S is susceptible. Using confocal laser scanning microscopy, initial fungal penetration into flag leaves was identical in both cultivars, with directional germ-tube growth towards stomata that were penetrated without the formation of an appressorium, followed by differentiation of a substomatal vesicle, infection hyphae, haustorial mother cells and haustoria. During the following 4 days, further fungal development occurred more quickly in the resistant than in the susceptible cultivar. However, by 7 days postinoculation (dpi) the situation changed, with exponential growth of the pathogen occurring only in the susceptible line. Induced cellular lignification, a typical defence reaction of cereals, was observed at 4 dpi in the resistant cultivar, and 2 days later lignified tissue completely surrounded the fungal colonies. In the susceptible cultivar, isolated lignified host cells occurred at 6 dpi, and long, unbranched fungal hyphae outgrowing the resistance reaction were observed. 相似文献
62.
Wei-Qin Wang Tomohide Natsuaki Yoshitaka Kosaka Seiichi Okuda 《Journal of General Plant Pathology》2006,72(1):52-56
To identify possible sites of viral attenuation, the complete nucleotide sequences of two isolates of Zucchini yellow mosaic virus (ZYMV) were determined; a severe isolate Z5-1 and an attenuated isolate from Z5-1 (designated ZYMV-2002). The viral genome
of both isolates consisted of 9593 nucleotides in size and contained an open reading frame encoding a single polyprotein of
3080 amino acids. Comparison of the nucleotide sequences for Z5-1 and ZYMV-2002 revealed 14 nucleotide mutations, resulting
in seven amino acid substitutions with four in the HC-Pro region, two in the CI region, and one in the NIb region. These results
provide a genetic basis for future manipulation of the ZYMV reverse genetics system.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB188115
and AB188116 相似文献
63.
黄羽肉鸡IGF-1基因单核苷酸多态性与生长性状的相关研究 总被引:14,自引:0,他引:14
本试验将类胰岛素生长因子1(IGF-1)作为研究肉鸡生长的候选基因,以海门京海集团的第二世代黄羽肉鸡为试验材料,根据鸡IGF-1基因DNA序列设计引物,采用PCR-SSCP方法进行SNP检测和基因型分析,探讨IGF-1基因多态性与鸡生长性状之间的关系。于IGF-1基因外显子1上发现一处突变。这个突变产生的不同基因型与鸡生长性状进行的统计分析结果表明,个体的1日龄初生重、4周龄、12周龄及300日龄成年体重在不同基因型之间均存在显著差异(P<0.05)。AA基因型1日龄初生重、4周龄、8周龄及300日龄成年体重均显著高于BB基因型个体(P<0.05)。推测可以将IGF-1基因应用于鸡生长的标记辅助选择育种实践。 相似文献
64.
黄羽肉鸡群体遗传变异的微卫星分析及其与体重杂种优势的关系 总被引:3,自引:0,他引:3
选用10对微卫星引物分析了黄羽肉鸡A、B、C3个品系的遗传结构和差异,并对微卫星标记所计算的个体间遗传距离与C×B、C×A杂交后代的初生至8周龄体重的杂种优势和杂种优势率进行了相关分析。结果表明,10个微卫星标记中有9个表现出多态性,多态信息含量(PIC)和群体杂合度(Heterozigosity)分别为0·4400和0·6811,各品系、各微卫星基因座上都表现出一定差异。利用9个多态微卫星标记计算得出的亲本个体间的遗传距离与后代杂种优势率间多数没有显著的相关(P>0·05),仅C×B组合中亲本个体间平均遗传距离与第8周龄体重杂种优势和杂种优势率间相关显著(P<0·05)。 相似文献
65.
66.
饲粮不同营养水平对黄羽肉鸡能量和粗蛋白质表观代谢率的影响 总被引:1,自引:0,他引:1
为探讨饲粮的不同营养水平对黄羽肉鸡能量和粗蛋白质表观代谢率的影响,用甘肃黄鸡在4周龄和8周龄分别做2期代谢试验。第1期试验设A、B、C组,第2期设A、BH、B、BL、C组。试验结果表明:能量代谢率,第1期A、B、C组分别为76.68%、69.55%和65.51%,组间差异均显著(P<0.05);第2期BH、A和B组(71.50%、71.00%和69.31%)3组均显著地高于BL和C组(P<0.05)。粗蛋白质代谢率,第1期A、B、C组分别为54.63%、52.27%和51.82%,第2期B和BH组最高(43.80%、43.22%),但两期组间差异均不显著(P>0.05)。由此可得出,营养水平饲粮条件下中速型黄羽鸡能量和粗蛋白质代谢率最高。 相似文献
67.
从女贞果实中提取色素,对其进行分离纯化,测定其光谱;并采用正交设计方法对女贞果实色素的稳定性进行试验.结果表明:女贞果实色素在20℃,pH值2,氧化剂浓度为0.01%的情况下稳定性好;同时表明pH值对其稳定性影响很小;温度达到80℃时该色素受到破坏,氧化剂(H2O2)的浓度很低时(0.01%),色素就会受到破坏. 相似文献
68.
从采集于海南儋州地区表现黄脉症状的长蒴母草(Lindernia anagallis)上分离到病毒分离物L2, DNA-A全序列分析结果表明, 全长2739个核苷酸(nt)(GenBank登录号:AY795900), 共编码6个ORF, 其中病毒链编码AV1(CP)、AV2, 互补链编码AC1、AC2、AC3、AC4。利用BLAST程序对DNA-A进行分析表明, 与L2 DNA-A有同源关系的病毒均为双生病毒科(Geminiviridae)菜豆金色黄花叶病毒属(Begomovirus)成员。进一步比较发现, L2 DNA-A与我国广东报道的广东番茄曲叶病毒(Tomato leaf curl Guangdong virus, ToLCGuV)(AY602165)全基因组核苷酸序列的同源性最近, 仅为77.0%, 说明L2为Begomovirus中的一个新种, 命名为长蒴母草黄脉病毒(Lindernia anagallis yellow vein virus, LAYVV)。与L2的IR区及各基因编码的氨基酸序列有最高同源性的病毒均来源于亚洲。利用DNA-B特异引物和DNA-β的特异引物, 均未检测到DNA-B和卫星DNA-β的存在。 相似文献
69.
Tetsuo Tamada 《Journal of General Plant Pathology》2007,73(1):76-80
Four lines (designated MR0, MR1, MR2, and M8) from 13 accessions of Beta vulgaris subsp. maritima were selected on the basis of phenotypes produced after foliar rub-inoculation with Beet necrotic yellow vein virus (BNYVV). The susceptible phenotype developed bright yellow local lesions, whereas the resistant phenotype had symptoms ranging
from no visible lesions to necrotic lesions at the inoculation site. MR1 and MR2 lines had a resistant phenotype depending
on the isolate and the MR0 line was susceptible to all isolates of BNYVV tested. The M8 line was highly susceptible; the virus
spread systemically and caused severe stunting. These plant lines will be useful for distinguishing BNYVV isolates having
different pathogenicities, especially those controlled by RNA3 and/or RNA5. 相似文献
70.
A. Calonnec R. Johnson 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(8):835-847
Crosses of a wheat line TP1295 with the cultivar Chinese Spring monosomic series were used to locate, on chromosome 1D, a major gene for resistance to isolate WYR 85-22 of race 6E0 of Puccinia striiformis. The gene is designated as Yr25 and is probably present in several of the cultivars currently widely used for differentiating races of this pathogen. The expression of the gene was modified by the environment and by at least one minor gene which may be located on chromosome 6A. In F2 and F3 generations from a cross between TP1295 and euploid Chinese Spring, a wide range of variation in infection type (IT) was observed. This precluded the classification of the plants as either resistant or susceptible, so they were assigned to 6 classes and analyzed by factorial correspondence analysis and non-hierarchical classification. When all F3 plants in a family were fully resistant, like TP1295 itself (IT ;), both Yr25 and the modifying gene were assumed to be present and homozygous. In environments favourable to expression of the gene, families thought to carry Yr25 alone had a distribution of ITs from fully resistant (IT ;) to intermediate (IT 2, rarely 3 or 3+). This F3 analysis indicated that use of IT data alone, in the monosomic analysis, would not reveal the chromosomal location of the genes and that chromosome counting of numerous plants was necessary. As well as indicating the chromosomes carrying the genes for resistance to isolate WYR 85-22, the data showed that plants monosomic for chromosomes 5B and 5D were more resistant than the corresponding disomics, indicating that these chromosomes promote susceptibility and supporting other evidence of the effects of these chromosomes on yellow rust resistance. 相似文献