用TOPSIS综合评价小麦种质资源对麦长管蚜的抗虫性

以107份小麦（Triticum aestivum L.）种质资源为材料,分析了各基因型的抗麦长管蚜特征,共发现1份高抗材料和19份中抗材料。另外,对各供试材料的分蘖数、千粒重、抽穗期等10个小麦农艺性状指标进行了调查。经相关性检验发现,分蘖数和株高均与抗虫指数和抗虫级别呈极显著负相关。综合抗虫指数、抗虫级别和10个小麦农艺性状共12个特征数据进行TOPSIS分析,结果发现,来自伊朗的小麦品种PI 623081表现最好,其次是华麦8号、黔麦15和PI 634770等,新麦19的表现最差。研究结果对小麦的抗虫育种工作具有极其重要的指导意义。     

Spatial Simulation of Epizootics Caused by Beauveria bassiana in Russian Wheat Aphid Populations

Models of disease dynamics commonly make the assumption of spatial homogeneity in the underlying host population. However, insect behavior may result in spatially heterogeneous populations with which pathogens interact. We modified a simulation model of temporal and spatial population dynamics of the Russian wheat aphid, Diuraphis noxia, on preferred or nonpreferred host plants, by incorporating effects of the entomopathogenic fungus, Beauveria bassiana. Epizootic parameters included time from inoculation of aphids until death, duration of sporulation, and estimated exposure probability. Simulations first predicted results of previously described experiments in which D. noxia adults were inoculated with conidial suspensions or water and placed on wheat or oat seedlings in 81-plant grids in cages. Subsequently, large-scale simulations were run for hypothetical field situations on 50 × 50-plant grids of wheat or oat. With B. bassiana present for both cage and larger scale simulations, results indicated that, on oat, an expanding infection front lagged behind the expanding aphid population front. Continual aphid movement from hosts resulted in many escapes, and the aphid population persisted at slightly reduced levels. On the preferred wheat host, patterns developed with pockets of infected aphids and other pockets of healthy aphids. Localized aphid populations that escaped initial infestation were able to proliferate, whereas other local populations were greatly reduced or became extinct due to lack of movement from the hosts, resulting in increased exposure to pathogen inoculum. Thus, proliferation and fluctuation of the pathogen were strongly influenced by the plant hosts' effects on aphid movement behavior. Incorporating spatial dynamics into disease models should prove useful in other efforts to predict biological control efficacy by entomopathogenic fungi in heterogeneous habitats.     

小麦种质对麦长管蚜的抗性鉴定与评价

2002-2005年连续4年,选用蚜情指数法对小麦种质进行麦长管蚜田间自然感蚜抗性鉴定,从2000份小麦种质中筛选出不同抗性材料34份,占总鉴定材料的1.7%,其中高抗种质5份、抗性种质9份、中抗种质20份。利用苗期室内接虫法,对部分抗感小麦种质进行鉴定,结果表明,苗期的抗性表现与成株期基本一致。对杂交组合临远207(抗)×Witchita(感)的F1、F2的抗性遗传分析表明,临远207对麦长管蚜的抗性由1对显性单基因控制。     

High Levels of Resistance in Agropyron Species to Barley Yellow Dwarf and Wheat Streak Mosaic Viruses

Several Agropyron species were tested for new sources of resistance to barley yellow dwarf virus (Bydv ) and wheat streak mosaic virus (WSMV). With BYDV strain PAV, 11 of the 17 Agropyron species showed no virus transmission when plants were given access feed by viruliferous Rhopalosiphum padi. Similar trials with BYDV strain RMV (vectored by R. maidis) indicated that all plants, except susceptible control plants, remained virus free. Virus status was confirmed by enzyme-linked immunosorbent assays. When plants were mechanically inoculated with WSMV, 11 Agropyron species failed to express symptoms, while five other species showed a segregating response or had some accessions segregating and some resistant. Test results suggest that resistance to BYDV and WSMV in Agropyron species does not appear to be correlated with any specific genome of Agropyron species although most of the Agropyron species containing S genome were resistant to BYDV and WSMV.     

Proteomic analysis of secreted saliva from Russian Wheat Aphid (Diuraphis noxia Kurd.) biotypes that differ in virulence to wheat

Diuraphis noxia, Russian Wheat Aphid (RWA), biotypes are classified by their differential virulence to wheat varieties containing resistance genes. RWA salivary proteins, unlike those of most aphid species, cause foliar damage and physiological alterations in plants. A comparative proteomic analysis of secreted saliva from four differentially virulent RWA biotypes identified thirty-four individual proteins. The five major proteins were glucose dehydrogenase, lipophorin, chitinase, CiV16.8g1-like, and lava lamp. Fourteen proteins quantitatively varied among biotypes; trehalase, β-N-acetylglucosaminidase (chitinase), two separate glucose dehydrogenases, calreticulin, aminopeptidase, acetylglucosaminyltransferase, hydroxymethylglutaryl-CoA lyase, acyltransferase, ficolin-3, lava lamp, retinaldehyde-binding protein, and two proteins of unknown function. Fifty-four percent of spectral counts were associated with glucose dehydrogenase, which is thought to detoxify plant defensive compounds. One-dimensional electrophoresis detected nine protein bands from 9 to 60 kDa that quantitatively differed. Two-dimensional electrophoresis identified six major gel zones with quantitative and qualitative variance in proteins. Our findings reveal that the salivary proteome of RWA, a phytotoxic aphid, differs considerably from those reported for nonphytotoxic aphids. The potential roles of proteins used in the general plant feeding processes of aphids and those that are potential phytotoxins related to aphid virulence are discussed.     

Aphid Vectors of Barley Yellow Dwarf Virus in West-Central Morocco

The ability of seven aphid species, collected in west-central Morocco, to transmit barley yellow dwarf virus (BYDV) was determined. Aphids were either collected from grasses showing symptoms of BYDV infection or were allowed acquisition access to plants infected with a PAV-like isolate of BYDV before transfer to oat test plants. BYDV transmission by six of the seven aphid species was confirmed by ELISA test; only Melanaphis donacis failed to transmit. The six newly defined BYDV vector species brings the total known to occur in Morocco to ten.     

Sensitivity of Resistance to Net Blotch in Barley

The aim of this study was to demonstrate various methods of analysing terminal net blotch, Pyrenophora teres Drechs. f. teres Smedeg., severity data from 15 spring barleys, Hordeum vulgare L., grown in Finnish official variety trials in five environments. The analyses have been developed and used principally by plant breeders for assessing crop yield, but lend themselves to use by plant pathologists. Pyrenophora teres is the major barley phytopathogen in Finland and improved resistance to it is sought. Joint regression analysis (JRA) and an additive main effects and multiplicative interaction (AMMI) model were used to investigate the data. Statistically significant genotype by environment (GE) interaction for resistance was indicated, and this included qualitative (crossover) interactions among genotypes over environments. A stable, non-sensitive, response to net blotch over environments, combined with a low mean score for terminal severity of the disease characterized the six-row barley 'Thule' which showed statistically significant crossover interaction only with 'Tyra'. 'Kustaa' exhibited the lowest mean terminal net blotch severity, but was relatively sensitive to net blotch. 'Arve' exhibited severe terminal net blotch in all environments, was relatively sensitive to environment and exhibited no crossover interaction with other genotypes. AMMI analysis appeared to represent a useful method for analysing these disease severity data, facilitating the selection of useful sources of resistance. Plots of AMMI-adjusted mean net blotch severities against first principal component axis (PCA) scores were informative for differentiating genotype response over environments, and are therefore potentially useful to plant pathologists and barley breeders seeking to gauge and subsequently improve the resistance status of barley to net blotch.     

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.     

Russian Wheat Aphid,Diuraphis noxia in the Czech Republic – cause of the significant population decrease

Diuraphis noxia is a newly established alien pest in the Czech Republic. There were two population explosions during the period 1993–2012. A successful overwintering of the anholocyclic populations of D. noxia was the cause of a population explosion in the oncoming growth season. Viviparous parthenogenetic females of the anholocyclic populations and diapausing eggs of holocyclic populations could overwinter at the same time. Analysis of the course of winter temperatures showed that a complete winter mortality of anholocyclic populations depended mainly on the duration of the freezing period, when temperature dropped below ?5°C, and on the intensity of the frost. We proposed the cumulative effective freeze (in minus degree days) as a key parameter for the aphid anholocyclic population's mortality during overwintering. This parameter equalled ?10.1 degree days for relatively warm winter period 2006–2007, whereas in the relatively cold winter period of 2009–2010, this parameter reached ?87.1 DD, which caused complete mortality of anholocyclic populations. A cumulative effective freeze could be used for short‐time prognosis of D. noxia population explosion.     

抗黄矮病小麦新品系YW443的分子细胞遗传学鉴定

以小麦－中间偃麦草二体附加系Ｌ１衍生抗病系ＰＰ９－１为抗源,与小麦推广品种陕７８５９．丰抗８号杂交并自交,在Ｆ６代中选到农艺性状优良的高抗黄矮病小麦新品系ＹＷ４４３。对ＹＷ４４３及其亲本进行抗病性鉴定。结果表明：ＹＷ４４３高抗大麦黄矮病毒ＧＰＶ、ＧＡＶ株系。利用基因组原位杂交,ＲＦＬＰ分析和ＲＡＰＤ分析,研究诉遗传构成及其抗病基因染色体归属。结果表明：ＹＷ４４３（２ｎ＝４３）的遗传构成了４０条（２     

Aphid Acceptance of Barley Exposed to Volatile Phytochemicals Differs Between Plants Exposed in Daylight and Darkness

It is well known that volatile cues from damaged plants may induce resistance in neighboring plants. Much less is known about the effects of volatile interaction between undamaged plants. In this study, barley plants, Hordeum vulgare cv. Kara, were exposed to volatiles from undamaged plants of barley cv. Alva or thistle Cirsium vulgare, and to the volatile phytochemicals, methyl salicylate or methyl jasmonate. Exposures were made either during natural daylight or darkness. Acceptance of exposed plants by the aphid Rhopalosiphum padi was assessed, as well as the expression of putative marker genes for the different treatments. Aphid acceptance of plants exposed to either barley or C. vulgare was significantly reduced, and an effect of the volatiles from undamaged plants was confirmed by the induction of pathogenesis-related protein, PR1a in exposed plants. However the effect on aphid acceptance was seen only when plants were exposed during darkness, whereas PR1a was induced only after treatment during daylight. Aphid acceptance of plants exposed to either methyl salicylate or methyl jasmonate was significantly reduced, but only when plants were exposed to the chemicals during daylight. AOS2 (allene oxide synthase) was induced by methyl jasmonate and BCI-4 (barley chemical inducible gene-4) by methyl salicylate in both daylight and darkness. It is concluded that (a) the effects on aphids of exposing barley to volatile phytochemicals was influenced by the presence or absence of light and (b) the response of barley to methyl salicylate/methyl jasmonate and to volatiles from undamaged plants differed at the gene and herbivore level.Key Words: methyl jasmonate, methyl salicylate, allelobiosis, barley, PR1, allene oxide synthase, Rhopalosiphum padi, light     

Cereal Aphid Colony Turnover and Persistence in Winter Wheat

An understanding of spatial and temporal processes in agricultural ecosystems provides a basis for rational decision-making with regards to the management and husbandry of crops, supporting the implementation of integrated farming strategies. In this study we investigated the spatial and temporal distribution of aphid pests (Sitobion avenae and Metopolophium dirhodum) within winter wheat fields. Using an intensive sampling programme we investigated distributions at both the small (single shoot) and large (field) scales. Within two fields, a grid with 82 locations was established (area 120 m by 168 m). At each location, 25 shoots were individually marked and aphid counts by observation conducted on 21 and 22 occasions as the crop matured, resulting in 43,050 and 45,100 counts being conducted in the two fields respectively. We quantified field scale spatial distributions, demonstrating that spatial pattern generally emerged, with temporal stability being both species- and field- dependent. We then measured turnover of colonies at the small (individual shoot) and large (field) scales by comparing consecutive pairs of sampling occasions. Four turnover categories were defined: Empty (no aphids recorded on either occasion); Colonised (aphids recorded on the second occasion but not the first); Extinction (aphids recorded on the first occasion but not the second); Stable (aphids recorded on both occasions). At the field scale, population stability soon established, but, at the small scale there was a consistently high proportion of unoccupied shoots with considerable colonisation and extinction and low stability. The redistribution of aphids within the crop at the local scale is a vulnerability which could be used to disrupt population development – by mediating exposure to ground-active natural enemies and by incurring a metabolic cost caused by the physiological demands to re-establish on a nearby host plant.