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Phenolic acids are major components of cell walls in wheat and have important implications on human health as antioxidants with anti-tumor activity. Our objectives were to identify phenolic acid genes in wheat by single nucleotide polymorphisms (SNPs) detected within the coding sequences of candidate genes, and to identify chromosomal regions associated with single phenolic acids and total soluble phenolic compounds. A set of candidate genes involved in the biosynthesis of hydroxycinnamic acid derivatives were identified by comparative genomics. SNPs found in the coding sequences of six genes (PAL1, PAL2, C4H, C3H, COMT1 and COMT2) were used to determine their chromosomal location and accurate map position on two reference consensus linkage maps. The genome-wide association study (GWAS), based on genotyping a tetraploid wheat collection with 81,587 gene-associated SNPs, detected 22 quantitative trait loci (QTL) distributed on almost all durum wheat chromosomes. Two QTL for p-coumaric acid were coincident with the phenylalanine ammonia-lyase (PAL2) and p-coumarate 3-hydroxylase (C3H) genes on chromosome arms 2AL and 1AL, respectively. The availability of candidate gene-based markers can allow elucidating the mechanism of phenolic acids accumulation in wheat kernels and exploiting the genetic variability of phenolic acids content for the nutritional improvement of wheat end-products. 相似文献
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中国的甘蓝型油莱高芥酸品种芥酸含量比外国的高芥酸品种高6~10%。本研究用两个中国高芥酸品种与一个加拿大和一个日本高芥酸品种杂交,其Fl与低芥酸品种测交。F2代和测交后代的分离结果表明,这些材料中的芥酸基因是等位的,也无明显的证据表明它们是复等位基因,因而很可能是同一的。这两类品种芥酸含量的差异可能与遗传背景或修饰基因有关。 相似文献
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高梁不育系Tx3197A减数分裂中染色体行为 总被引:3,自引:0,他引:3
以Tx3197B和晋粱5号为对照,对Tx3197A进行了观察。结果发现,减数分裂前期Ⅰ和中期Ⅰ无明显异常。自后期Ⅰ开始,染色体行为出现了多类型的异常现象,导致减数分裂不能正常进行,无法形成花粉粒,从而产生雄性不育。 相似文献
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利用雄性不育选育辣椒新品种农大082 总被引:1,自引:0,他引:1
农大082是以雄性不育系S200243A为母本,恢复系S200244C为父本配制而成的微辣型辣椒一代杂种。中早熟,从定植到始收30d(天)左右,果实羊角形,果纵径17—20cm,横径3-4cm,嫩果深绿色,成熟果红色,味微辣,果肉脆嫩,平均单果质量40—60g,667m^2产量3200-4600kg,抗TMV,耐CMV。已在北京、河北、四川、黑龙江等地示范推广逾400hm^2。 相似文献
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Z. K. Gerechter-Amitai Adriana Grama C. H. Van Silfhout Frida Kleitman 《European journal of plant pathology / European Foundation for Plant Pathology》1989,95(2):79-83
A comparison was made between the genes in 29 new selections of wild emmer wheat resistant to yellow rust over wide geographic areas and the previously extensively studied selectionTriticum dicoccoides G-25. In 23 selections the resistance may be conferred by 1 dominant gene; these include 11 selections in which the gene is different from the dominant gene in sel. G-25 and two others in which the genes were closely linked or allelic to the gene in G-25, differing from sel. G-25 by race-specificity. Two dominant genes different from the gene in sel. G-25, seem to be present in one selection. In five selections the resistance may be conferred by one or two recessive genes, including three instances in which the recessive gene was associated with a dominat gene. Our findings show that at least 19 out of the 29 selections studied possess genes which are different from the gene inT. dicoccoides sel. G-25.Samenvatting In dit onderzoek werden 29 nieuwe resistente wilde-emmer selecties (Triticum dicoccoides) gekruist met de reeds uitvoerig bestudeerde resistente selectie G-25, om na te gaan of de resistentie van de nieuwe selecties wordt veroorzaakt door genen op dezelfde locus als het dominante gen in sel. G-25 of dat er andere loci bij zijn betrokken. De ouders, de F1-en F2-populaties van een bepaalade selectie werden in het kiemplantstadium getoetst met één Israëlisch gele-roest isolaat van fysio 2E0 of van fysio 2E18. In de uitsplitsende F2-populaties werden de niet-sporulerende planten als resistent beschouwd en de sporulerende als vatbaar.In de F2-populaties van 12 herkomsten werden geen vatbare planten gevonden, hetgeen er op duidt dat de resistentie wordt veroorzaakt door een gen op dezelfde locus als het gen in G-25 of door een gen dat neuw gekoppeld is aan het gen in G-25. Voor twee van deze herkomsten kan op basis van een fysio-specifieke interactie worden vastgesteld dat de resistentie berust op allelen die verschillen van het allel in sel. G-25. In 11 herkomsten werd een uitsplitsing voor twee dominante gene gevonden (RS=151), waarbij het tweede dominante gen uit de getoetste nieuwe selectie afkomstig is. De aanwezigheid van twee dominante genen verschillend van het gen in sel. G-25 werd gevonden in één herkomst (631). In de overige vijf selecties bleek de resistentie te worden veroorzaakt door één of twee recessieve genen waarnaast in drie gevallen ook nog een dominant gen werd gevonden.De resultaten tonen aan dat tenminste 19 van de 29 bestudeerde selecties resistentiegenen bezitten die verschillen van het gen inT. dicoccoides sel. G-25. Slechts in twee van deze selecties kan het gen allel zijn met het gen in sel. G-25. 相似文献
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对在山东的济南、平度、莱西、烟台种植的几种陆地棉(Gossypium hirsutumL.)核雄性不育材料的育性表现进行了研究,结果表明:洞A不育系的衍生材料MB、MA在不同气候条件下有育性的变化。在济南高度不育,可作为不育系。在其他几个地区表现不同程度的可育。其中MB在平度有相当好的育性,能正常结铃。而双隐性核不育材料59A、62A未能观察到育性变化。本文就核不育材料在棉花杂交制种中的应用前景及需深入研究的问题作了探讨。 相似文献
10.
Potato diseases caused by soft rot erwinias: an overview of pathogenesis 总被引:17,自引:0,他引:17
M. C. M. Pérombelon† 《Plant pathology》2002,51(1):1-12
Three soft rot erwinias, Erwinia carotovora ssp. carotovora , E. carotovora ssp. atroseptica and E. chrysanthemi are associated with potatoes causing tuber soft rot and blackleg (stem rot). Latent infection of tubers and stems is widespread. As opportunistic pathogens, the bacteria tend to cause disease when potato resistance is impaired. Pathogenesis or disease development in potato tubers and stems is discussed in terms of the interaction between pathogen, host and environment, microbial competition and recent findings on the molecular basis of pathogenicity. Emphasis is placed on the role of free water and anaerobiosis in weakening tuber resistance and in providing nutrient for erwinias to multiply. Blackleg symptoms are expressed when erwinias predominate in rotting mother tubers, invade the stems and multiply in xylem vessels under favourable weather conditions. Soft rot erwinias tend to out-compete other bacteria in tuber rots because of their ability to produce larger quantities of a wider range of cell wall-degrading enzymes. However, despite extensive studies on their induction, regulation and secretion, little is known about the precise role of the different enzymes in pathogenesis. The putative role of quorum-sensing regulation of these enzymes in disease development is evaluated. The role certain pathogenicity-related characters, including motility, adhesion, siderophores, detoxifying systems and the hrp gene complex, common to most bacteria including symbionts and saprophytes, could play in latent and active infections is also discussed. 相似文献