带有Ae.triuncialis抗白粉病基因的普通小麦-Ae.triuncialis单体附加系的培育

通过中国春Tal kr phlb基因综合体与Ae.triuncialis杂交、回交、自交及抗白粉病、细胞学鉴定,第一次获得了带有Ae.triuncialis抗白粉病基因的普通小麦-Ae.triuncialis单体附加系。 For the first time,the common wheat-Ae.trinucialis monosomic addition lines with resistant gene of Ae.triuncialis to powdery mildew were obtained by crosses and backcrosses between Chinese Spring Tal krph1b plants and Ae.triuncialis with Chinese Spring and identification of powdery mildew and cytology of their progenies.     

大麦DNA导入小麦产生抗白粉病变异的遗传研究

本研究将抗白粉病的大麦DNA通过花粉管途径直接导入感病的小麦品种花76中,后代出现13株抗白粉病变异株。其中5株在以后的世代中抗性稳定,另8株则继续分离。第2带分离株系的抗病株形成的第3代株系（或株行）中,抗性有分离的株行与无分离的株行比例为1.9:1,而分离株行内抗病株与不抗病株之比为3.35:1。抗性稳定株系与感病亲本杂交,F1表现高抗病,再与感病亲本回交,后代抗感病株比例为1:1,自交F2的比例为2.8:1。说明所获得的抗白粉病性受一对完全显性基因控制,抗病为显性。与已知抗白粉病基因的比较表明,这个抗病基因可能是来自大麦的一个新基因。13 Variant plants with immunity and high-resistance to powdery mildew were found in D1 generation from introducing resistant barley DNA into susceptible wheat cultivar, through pollen tube pathway after self pollination.Of the variants, 5 plants for the resistance had been stable and the other 8 plants segregated insuccessive generation.The ratio of segregating and stable plant-rows was 1.9:1 in D3 plant-rows derived from resistant plants of segregating D2-lines,and the ratio of resistant plants and susceptible plants was 3.35:1 among the segregating D3 plant-rows.The F1 -plants from crosses between stable resistant variants and susceptible parents were higgh resistant to powdery mildew.The ratio of resistant and susceptible plants was 1:1 in progenies of backcross of the F1 and susceptible parents, and this ratio was 2.8:1 in the F2 generation from the F1 selfing. Thus it can be seen that the resistance obtained is camtrolled by a pair of genes, the resistance is dominant. The results in comparison with known powdery mildew resistance genes in wheat indicated that the resistant gene obtained would be a new one from barley.     

大麦DNA导入小麦产生抗白粉病变异的遗传研究

本研究将抗白粉病的大麦DNA通过花粉管途径直接导入感病的小麦品种花76中,后代出现13株抗白粉病变异株。其中5株在以后的世代中抗性稳定,另8株则继续分离。第2带分离株系的抗病株形成的第3代株系（或株行）中,抗性有分离的株行与无分离的株行比例为1.9:1,而分离株行内抗病株与不抗病株之比为3.35:1。抗性稳定株系与感病亲本杂交,F1表现高抗病,再与感病亲本回交,后代抗感病株比例为1:1,自交F2的比例为2.8:1。说明所获得的抗白粉病性受一对完全显性基因控制,抗病为显性。与已知抗白粉病基因的比较表明,这个抗病基因可能是来自大麦的一个新基因。13 Variant plants with immunity and high-resistance to powdery mildew were found in D1 generation from introducing resistant barley DNA into susceptible wheat cultivar, through pollen tube pathway after self pollination.Of the variants, 5 plants for the resistance had been stable and the other 8 plants segregated insuccessive generation.The ratio of segregating and stable plant-rows was 1.9:1 in D3 plant-rows derived from resistant plants of segregating D2-lines,and the ratio of resistant plants and susceptible plants was 3.35:1 among the segregating D3 plant-rows.The F1 -plants from crosses between stable resistant variants and susceptible parents were higgh resistant to powdery mildew.The ratio of resistant and susceptible plants was 1:1 in progenies of backcross of the F1 and susceptible parents, and this ratio was 2.8:1 in the F2 generation from the F1 selfing. Thus it can be seen that the resistance obtained is camtrolled by a pair of genes, the resistance is dominant. The results in comparison with known powdery mildew resistance genes in wheat indicated that the resistant gene obtained would be a new one from barley.     

Development of Triticum aestivum-Leymus racemosus translocation lines using gametocidal chromosomes

Maan[1] and Endo[2] et al. first reported that some chromosomes from Ae. longgissima, Ae. sharonensis and Ae. triuncialis showed preferential transmission when introduced into wheat background. The mechanism for this phenomenon rests with the fact that contrary to the normal fertility of gametes with these chromosomes, chromosome structural aberrations occur seriously in the gametes without these chromosomes, causing less compatibility in selective fertilization and resulting in semi-sterilit…     

Hyperparasites of the genus shape Ampelomyces on powdery mildew fungi in Serbia

From 1982 to 1996, in Serbia, 229 species of plants infected with powdery mildew were collected. Seventy-five species had hyperparasites of the genus Ampelomyces. Distribution analysis showed that hyperparasitism was greatest on plants from the families Asteraceae, Apiaceae and Fabaceae. Ampelomyces was not found on the family Poaceae. It was reported for the first time on the families Amygdalaceae, Cornaceae, Grossulariaceae, Plantaginaceae, Rhamnaceae and other 37 plant species. Hyperparasites of the genus Ampelomyces were found on 33 different species of fungi that are causal agents of powdery mildews. They are reported for the first time on nine species. Pycnidial size varied in the range 45–106 × 25.5–40.5 μm and conidia from 4.5–10.5 × 2.5–4.8 μm. This revised version was published online in June 2006 with corrections to the Cover Date.     

中国春小麦株高、育性近等基因系的建立及应用

以矮败小麦和中国春小麦为材料,经过杂交和连续回交,得到了中国春小麦遗传背景的分别表现矮秆不育、矮秆可育、高秆不育、高秆可育的近等基因系。根据近等基因系各成员系的株高表现,计算出矮秆基因Rht10的降秆强度是69.8%。借助于赤霉酸处理,在幼芽期就可分出矮败中国春小麦后代的不育株与可育株。 Abstract：　Use Dwarfing Male-sterile Wheat and cv. Chinese Spring as parents, after cross and continuously back cross, the isogenic lines with Chinese Spring background were developed. These lines include dwarfing male-sterile line, dwarfing fertile line, tall male-sterile line and tall fertile line. The dwarfing intensity of gene Rht10 was calculated to be 69.8% according the differences between the isogenic lines. Treated with GA3solution, the male-sterile and fertile plants in Chinese Spring Dwarfing Male-sterile Wheat can be identified clearly when they are seedlings.     

中国春小麦株高、育性近等基因系的建立及应用

以矮败小麦和中国春小麦为材料,经过杂交和连续回交,得到了中国春小麦遗传背景的分别表现矮秆不育、矮秆可育、高秆不育、高秆可育的近等基因系。根据近等基因系各成员系的株高表现,计算出矮秆基因Rht10的降秆强度是69.8%。借助于赤霉酸处理,在幼芽期就可分出矮败中国春小麦后代的不育株与可育株。 Abstract：　Use Dwarfing Male-sterile Wheat and cv. Chinese Spring as parents, after cross and continuously back cross, the isogenic lines with Chinese Spring background were developed. These lines include dwarfing male-sterile line, dwarfing fertile line, tall male-sterile line and tall fertile line. The dwarfing intensity of gene Rht10 was calculated to be 69.8% according the differences between the isogenic lines. Treated with GA3solution, the male-sterile and fertile plants in Chinese Spring Dwarfing Male-sterile Wheat can be identified clearly when they are seedlings.     

Development of Triticum aestivum-Leymus racemosus translocation lines using gametocidal chromosomes

Specific chromosomes of certain Aegilops species introduced into wheat genome background may often facilitate chromosome breakage and refusion, and finally result in a variety of chromosome restructuring. Such a phenomenon is commonly called gametocidal effect of the chromosomes. The chromosome 2C of Ae. cylindrica is one of such chromosomes. In the present study, scab resistant wheat-L. racemosus addition lines involving chromosomes Lr.2 and Lr.7 were crossed to wheat-Ae. cylindrica disomic addition line Add2C. Then F₁ hybrids were subsequently backcrossed with wheat cv “Chinese Spring”. BC₁ plants with chromosome structural aberration were identified by C-banding. In the self-pollinated progenies of these plants, three translocation lines were developed and characterized by mitotic and meiotic analysis combined with C-banding and fluorescent in situ hybridization (FISH) using biotin-labeled genomic DNA of L. racemosus as probe. Some other putative translocation lines to be further characterized were also found. The practicability and efficiency of the translocation between wheat and alien chromosomes induced by gametocidal chromosomes, as well as the potential use of the developed alien translocation lines were also discussed.     

Thinopyrum ponticum and Th. intermedium:the promising source of resistance to fungal and viral diseases of wheat

Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat （Ttricum aestivum）. Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characterization and application of the genes for fungal and viral disease-resistance derived from Th. ponticum and Th. intermedium.     

Origin and differentiation of Aegilops triuncialis L. as determined by esterase isozyme analysis

Summary Banding patterns of esterase isozymes in Aegilops triuncialis (2n = 28, genome formula C^uC^uCC) and its putative parental species, Ae. umbellulata (2n = 14, C^uC^u) and Ae. caudata (2n = 14, CC), were studied by the gel isoelectric focusing method using pH 6–8 carrier ampholite. Zymogram phenotypes of both parents were quite uniform. Seven zymogram phenotypes (designated as phenotypes 1 to 7) were found among the 260 strains of Ae. triuncialis examined. Of these phenotypes, phenotype 1 was identical to the zymogram phenotype produced by the ancestral species, Ae. umbellulata, and bands considered to have been derived from Ae. caudata were absent in this phenotype. Phenotype 3 had all bands of both parents. The other phenotypes differed greatly from phenotype 3. Therefore, phenotype 3 was considered to be most primitive of the 7 types, and the Ae. triuncialis strains which showed phenotype 3 to be the most primitive of the strains examined. If Ae. triuncialis originated as a hybrid between Ae. umbellulata and Ae. caudata, the zymogram phenotype must have been phenotype 3, in which the isozymes of both parental species are present. Whether the phenotypes other than type 3 were due to introgressive hybridization could not be verified, but they were considered in this article to be a consequence of a rearrangement of chromosomes.Contribution from the Laboratory of Genetics, Faculty of Agriculture, Kyoto University No. 432     

Evolutionary ecology along invasion fronts of the annual grass Aegilops triuncialis

Over the last two decades, Aegilops triuncialis (barbed goatgrass) has rapidly spread into many annual grassland and serpentine soil sites within California, USA. The capacity of this species to invade edaphically stressful serpentine soil is especially unusual. It is unclear whether genetic differentiation, phenotypic plasticity, or both have allowed A. triuncialis to invade competitive (i.e. high productivity non-serpentine annual grassland) and edaphically stressful (i.e. low productivity serpentine) environments. We used a reciprocal transplant field experiment to examine the effects of plasticity and genetic variation on A. triuncialis phenology and demography along invasion fronts associated with interspecific competition and edaphic gradients. We reciprocally transplanted seeds collected behind invasion fronts (core subpopulations) and along invasion fronts (edge subpopulations). For both gradient types we measured higher reproduction and population growth at invasion front edges. This was true for both edge and core subpopulation seed sources, suggesting that phenotypic plasticity may facilitate invasive spread. Consistent planting site effects indicated that phenotypic plasticity is a primary contributor to A. triuncialis demographic responses along interspecific competition gradients. In contrast, significant seed source effects suggest genetic differentiation along invasion fronts in serpentine edaphic gradients. Although persistent maternal environmental effects cannot be ruled out entirely, seed source effects suggest genetic differences between serpentine subpopulations located behind and beyond the invasion fronts for plant survival, plant size, total seed production, and individual seed size. Rapid expansion of A. triuncialis in California may reflect an evolutionary capacity in this species for both phenotypic plasticity and genetic differentiation.     

Introgression of powdery mildew resistance from Aegilops triuncialis into wheat through induced homeologous pairing

Journal of Plant Biochemistry and Biotechnology - Powdery mildew is a serious fungal disease of wheat caused by Blumeria graminis f. sp. tritici. Chromosome 5U of Aegilops triuncialis carrying...     

Genome‐specific introgression between wheat and its wild relative Aegilops triuncialis

Introgression of sequences from crop species in wild relatives is of fundamental and practical concern. Here, we address gene flow between cultivated wheat and its widespread polyploid relative, Aegilops triuncialis, using 12 EST‐SSR markers mapped on wheat chromosomes. The presence of wheat diagnostic alleles in natural populations of the barbed goatgrass growing in proximity to cultivated fields highlights that substantial gene flow occurred when both species coexisted. Furthermore, loci from the A subgenome of wheat were significantly less introgressed than sequences from other subgenomes, indicating differential introgression into Ae. triuncialis. Gene flow between such species sharing nonhomeologous chromosomes addresses the evolutionary outcomes of hybridization and may be important for efficient gene containment.     

Maternal and sibling factors induce dormancy in dimorphic seed pairs of Aegilops triuncialis

Germination and emergence are stimulated by environmental cues, but strongly influenced by maternal controls. However, traits related to seed dispersal may have important influences on germination as well. For example, the sibling rivalry hypothesis suggests that germination may be inhibited when sibling seeds remain within a single dispersal unit. These two influences on germination suggest different, and possibly conflicting, evolutionary strategies for optimizing individual fitness. Using an invasive annual grass that produces dispersal units with dimorphic seeds, I found significant reductions in seedling emergence that suggested the presence of both strong maternal and sibling influences on the germination of the smaller seed of dimorphic pairs. Both influences were capable of nearly complete germination suppression of the small seed, but there was no strong evidence for a hierarchy among the two factors. The maternal effect is consistent with a bet-hedging strategy for survival in variable environments where resource availability can be unpredictable, but the sibling effect likely represents a mechanism for reducing competition between closely related individuals, particularly under conditions of resource limitation.     

Flow sorting of C-genome chromosomes from wild relatives of wheat Aegilops markgrafii,Ae. triuncialis and Ae. cylindrica,and their molecular organization

Background and Aims Aegilops markgrafii (CC) and its natural hybrids Ae. triuncialis (U^tU^tC^tC^t) and Ae. cylindrica (D^cD^cC^cC^c) represent a rich reservoir of useful genes for improvement of bread wheat (Triticum aestivum), but the limited information available on their genome structure and the shortage of molecular (cyto-) genetic tools hamper the utilization of the extant genetic diversity. This study provides the complete karyotypes in the three species obtained after fluorescent in situ hybridization (FISH) with repetitive DNA probes, and evaluates the potential of flow cytometric chromosome sorting.Methods The flow karyotypes obtained after the analysis of 4'',6-diamidino-2-phenylindole (DAPI)-stained chromosomes were characterized and the chromosome content of the peaks on the flow karyotypes was determined by FISH. Twenty-nine conserved orthologous set (COS) markers covering all seven wheat homoeologous chromosome groups were used for PCR with DNA amplified from flow-sorted chromosomes and genomic DNA.Key Results FISH with repetitive DNA probes revealed that chromosomes 4C, 5C, 7C^t, T6U^tS.6U^tL-5C^tL, 1C^c and 5D^c could be sorted with purities ranging from 66 to 91 %, while the remaining chromosomes could be sorted in groups of 2–5. This identified a partial wheat–C-genome homology for group 4 and 5 chromosomes. In addition, 1C chromosomes were homologous with group 1 of wheat; a small segment from group 2 indicated 1C–2C rearrangement. An extensively rearranged structure of chromosome 7C relative to wheat was also detected.Conclusions The possibility of purifying Aegilops chromosomes provides an attractive opportunity to investigate the structure and evolution of the Aegilops C genome and to develop molecular tools to facilitate the identification of alien chromatin and support alien introgression breeding in bread wheat.     

Within- and trans-generational plasticity affects the opportunity for selection in barbed goatgrass (Aegilops triuncialis)

• Premise of the study: Environments are composed of selective agents, and environments may also modify the efficacy of these agents. Environments affect the rate of maximum evolutionary change by influencing variation in relative fitness (i.e., the opportunity for selection, or I). Within- and transgenerational plastic environmental responses may affect I, speeding or slowing processes of local adaptation. • Methods: We determined whether environmental factors affected the opportunity for selection (I) in Aegilops triuncialis (barbed goatgrass) by measuring I as a within- and transgenerational plastic response to two maternal glasshouse environments (serpentine/dry and loam/moist). We also determined whether this species’ two most common genetic lineages (determined by DNA microsatellite length polymorphism) varied in response to glasshouse treatments. • Key Results: Opportunity for selection was less for plants grown in the dry serpentine environment than for plants grown in the moist loam environment. This response varied between genetic lineages. The east lineage exhibited a within-generation response to the dry serpentine environment. For both seed mass and average seed weight in this lineage, the opportunity for selection was lower in dry serpentine than in moist loam. The west lineage had a transgenerational response to the dry serpentine such that the opportunity for selection for seed number and seed mass was lower for plants produced by mothers grown in dry serpentine than for plants produced by mothers in moist loam. • Conclusions: Phenotypic variation in relative fitness is constrained by the dry serpentine environment, which leads to lower evolvability in this environment. Within- and transgenerational effects of the environment may slow local adaptation to serpentine soils.     

利用离果山羊草3C染色体诱导簇毛麦4V染色体结构变异

通过普通小麦农林26-离果山羊草3C异附加系与普通小麦-簇毛麦4V（4D）代换系杂交,杂交F1代与普通小麦回交,综合运用染色体构型分析、C-分带和荧光原位杂交等技术从BC1F2、BC1F3代中鉴定出涉及簇毛麦4V染色体的易位系、端体、等臂染色体系等变异植株,表明离果山羊草3C染色体可有效诱发簇毛麦4V染色体结构变异,是创造小麦-簇毛麦4V易位系的一种有效途径。