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571.
Elucidation of meiotic nuclear restitution mechanisms in potato through analysis of microtubular cytoskeleton 总被引:3,自引:0,他引:3
Clara Conicella Antonella Capo Maria Cammareri Angela Errico Natalia Shamina Luigi M. Monti 《Euphytica》2003,133(1):107-115
DNAs of 693 isolates of bacterial blight pathogen of rice, Xanthomonas oryzae pv. oryzae (Xoo), were characterized using PCR-based primers pJEL1 and pJEL2. The pathogen populations were grouped into 97 haplotypes based on DNA-banding patterns. An un-weighted pair-group method
using arithmetic averages (UPGMA) indicated a high level of diversity in the pathogen isolates (51 lineages of Xoo at a 70% similarity level). Among these, lineages 5, 7, 27, and 29 are widely distributed and others are localized in the
northern region of India. The isolates represent lineage-27, were prevalent in the entire disease-prone area in the region
except at Ferozepur. Pathotyping data of the representative isolates of each lineage also indicate 17 different reaction patterns
on a set of isogenic lines. Resistance genes
xa8 and Xa21 were the most effective followed by xa5, and Xa7 against Xoo isolates prevalent in northern India. Different genes in combinations (xa5+xa13, xa5+Xa21, xa13+Xa21, and xa5+xa13+Xa21) in IR24 genetic background provided better protection against all the pathogen isolates tested in this study than did the
component genes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
572.
Summary Since 1880 yellow disease has been known as a very serious disease in hyacinth. The breeding of resistant varieties can constitute an important contribution to the solution of this problem. Therefore it was first aseertained how the differences in resistance between the varieties can be determined as accurately as possible. To this end bulbs and plants of well known cultivars were inoculated with bacteria, and the degree of infection compared with that of bulbs grown in the field. It was found that the infection of the inoculated bulbs corresponded little, if at all, with infection in practice, but the infection of the inoculated leaves did. So the degree of leaf infection seems a useful selection criterion. Comparison of the infection of juvenile and adult plants also yielded an indication of the possibility of preselection for yellow disease resistance in seedling populations. 相似文献
573.
Improving bacterial blight resistance of'6078', an elite restorer line of hybrid rice, by molecular marker-assisted selection 总被引:12,自引:0,他引:12
Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (X00), is one of the most devastating diseases of rice world‐wide; it is also a serious problem of hybrid rice production in China. In this study, a molecular marker‐assisted introgression of Xa21, a gene highly resistant to a broad spectrum of Xoo strains, from ‘IRBB21’ was performed to improve the BB resistance of‘6078′, a new restorer line with high yielding potential. The entire process took one generation of crossing followed by three generations of backcrossing and one generation of selfing. The presence of Xa21 in each generation was determined by both polymerase chain reaction (PCR) and pathogen inoculation. Recombinations between Xa21 and flanking markers were identified by PCR analysis. Background selection was conducted in BC1F1 and BC2F1 using amplified fragment length polymorphism (AFLP) markers detecting a total of 129 polymorphic bands between‘6078’ and ‘IRBB21′. The individual selected in BC3F2, or‘6078′(Xa21), carried a fragment of less than 3.8 cM from the donor line in the Xa21 region on chromosome 11, and about 98.8% of the genetic background from the recurrent parent. The results showed that‘6078′(Xa21) had the same level and spectrum of BB resistance as the donor parent ‘IRBB21′, while maintaining the agronomic performance and combining ability of the original 6078. A significant increase in BB resistance was also achieved in the hybrid using 6078(Xa21) as the restorer line. 相似文献
574.
水稻抗白叶枯病基因及其抗病机理的研究进展 总被引:4,自引:2,他引:4
水稻白叶枯病是由Xanthomonasoryzaepv.oryzae致病菌引起的全球性水稻病害。到目前为止,已有26个抗病基因被发现,有10个基因已在染色体上被定位,包括显性基因Xa1、Xa4、Xa21andXa26(t)等和隐性基因Xa5、Xa13等。对大部分抗病基因的抗病机制了解还不是很清楚。利用标记辅助选择(MAS)进行抗病育种是防治白叶枯病的有效途径。在此,综述了已发现的抗水稻白叶枯病基因的种类、分子标记、抗病机制和在抗病育种中的应用。 相似文献
575.
福建柑桔溃疡病菌分化的初步研究 总被引:1,自引:0,他引:1
以日本(XC25和 XC29)和南京(XC31)菌株作对照,对从福建柑桔主要栽培品种上分离的28个柑桔溃疡病菌株进行培养性状,形态、生理生化、血清学,噬菌体敏感性和致病性的比较研究。试验初步表明,福建的柑桔溃疡病菌属于毒力较强的 A 致病型,且具有一定的分化。试验还表明,柑桔品种的抗病性变化较大。有感病、中抗和抗病等各种类型。在研究溃疡病菌菌系分化时,应选择中抗品种作为鉴别品种,采用无伤痍接种法较好。 相似文献
576.
为探究小檗碱对水稻细菌性条斑病菌Xanthomonas oryzae pv. oryzicola的抑菌机制,测定小檗碱对水稻细菌性条斑病菌GX13菌株的毒力、致病因子、细胞结构和能量代谢的影响,并利用Illumina-HiSeq高通量测序技术分析小檗碱对水稻细菌性条斑病菌菌体基因表达的影响。结果表明:经15μg/mL小檗碱处理后,GX13菌株侵染水稻品种玉丝占后引起水稻细菌性条斑病的病情指数为6.70,低于对照组;每1×108CFU菌体胞外多糖产量为1.58μg,显著低于对照的2.42μg;纤维素酶、蛋白酶、淀粉酶等胞外酶活性均低于对照组;与能量代谢相关的苹果酸脱氢酶(MDH)活性为1.42 U/g prot,低于对照组,而丙酮酸和三磷酸腺苷含量升高,分别为1.71μmol/mL和379.49μmol/g prot,均高于对照组。同时,细菌的生物膜形成受到抑制,细胞结构受到破坏。转录反应分析发现,与II型分泌系统相关的xpsD、xpsF和xpsM等基因、与III型分泌系统相关的hrcC、hrcJ、hrcN和hrcQ等基因、与胞外多糖分泌相关的gumF和gumI基因,以及与细胞结构与功能... 相似文献
577.
578.
表皮特异硫蛋白在硫代葡萄糖苷代谢调控中起着重要作用,包括催化异硫氰酸酯生成环腈类和腈类物质。本研究以西兰花为试验材料,在克隆表皮特异硫蛋白基因BoiEPS的基础上进行序列分析和表达分析,并初步明确其在野油菜黄单胞菌侵染下的功能。结果表明,BoiEPS基因全长1 270 bp,有1个长度为238 bp的内含子;编码区全长1 032 bp,编码343个氨基酸,编码蛋白具有2个Kelch结构域。系统发育分析结果表明,BoiEPS与来自芜菁、甘蓝型油菜的EPS聚为一组,但与其他十字花科植物的EPS处于不同分支。实时荧光定量PCR结果表明,BoiEPS的表达受野油菜黄单胞菌的诱导,在24 h的表达量最大;BoiEPS的过量表达可显著提高西兰花对黑腐病的抗性,病程相关蛋白基因BoPR1的表达量在3个过表达株系均明显增加。本研究结果为后续开展西兰花-黑腐病抗性机理研究奠定了理论基础。 相似文献
579.