大麦黄矮病毒侵染对燕麦光合及叶绿素荧光参数的影响

为探究燕麦在蚜虫和大麦黄矮病毒（Barley Yellow Dwarf Virus,BYDV）为害后的光合生理响应,本试验测定了燕麦接种蚜虫和BYDV后不同时间（0,7,14,21,28和35 d）的叶片光合和叶绿素荧光参数。结果表明,随着为害时间的延长,叶片叶绿素a（Chl a）、叶绿素b（Chl b）以及总叶绿素（T-Ch1）含量显著降低（P<0.05）,类胡萝卜素（Car）含量显著增加（P<0.05）,Chl a/Chl b先上升后稍有下降,接种BYDV 21 d后,Chl a/Chl b均增加至最大值,比CK处理高57.37%（P<0.05）;叶片净光合速率和水分利用效率下降,胞间CO₂浓度、气孔导度和蒸腾速率上升;同时最大荧光、潜在光化学效率、最大光化学效率、光化学淬灭系数、PS Ⅱ光化学量子产量和表观光合电子传递速率均呈现下降的趋势,非光化学猝灭系数上升。本研究表明BYDV侵染严重损伤了燕麦叶片的光合作用能力,其光合参数发生了显著变化,为探讨BYDV与燕麦的互作机理提供了一定的参考依据。     

A simple test for evaluation of transmission efficiency of barley yellow dwarf virus by aphids

Barley yellow dwarf virus (BYDV) transmission test systems involve the use of clip-cages or of whole plants in cages, which are both labor-intensive methods and require large controlled environment units. Employing detached leaves for assessment of the inoculation efficiency of aphids proved reliable for assessing transmission of a BYDV PAV-like isolate byRhopalosiphum padi. One use of the system could be for the rapid determination of the infectivity of field-collected aphids, an essential part of any epidemiological study of BYDV. http://www.phytoparasitica.org posting Aug. 14, 2002.     

抗黄矮病小麦种质的分子标记

应用基因组原位杂交技术分析了抗小麦黄矮病种质的遗传组成,研究表明小麦一中间但麦草部分双二倍体无芒中4(2n=56)具有40条小麦染色体、5对中间僵麦草染色体、3对小麦/中间僵麦草易位染色体,其中1对是罗伯逊氏易位染色体。结果表明无芒中4与远中5的遗传组成有明显差异,是两种不同类型的材料。抗黄矮病小麦种质F940418, T10     

Interactions Between <Emphasis Type="Italic">Barley yellow dwarf virus</Emphasis> and <Emphasis Type="Italic">Fusarium</Emphasis> spp. Affecting Development of Fusarium Head Blight of Wheat

Interactions between Barley yellow dwarf virus (BYDV) and Fusarium species causing Fusarium head blight (FHB) in winter wheat cvs Agent (susceptible to FHB) and Petrus (moderately resistant to FHB) were studied over three years (2001–2003) in outdoor pot experiments. FHB developed more rapidly in cv. Agent than in cv. Petrus. The spread of FHB was greater in BYDV-infected plants than in BYDV-free plants. Thousand grain weight (TGW) was reduced more in Fusarium-infected heads of cv. Agent than in cv. Petrus. A highly significant negative correlation was found between disease index and TGW in cv. Agent (r = −0.916), while in cv. Petrus the correlation was less significant (r = −0.765). Virus infection reduced TGW in cv. Petrus more than in cv. Agent. In plants with both infections, TGW reductions in cv. Petrus corresponded to those of BYDV infection, and in cv. Agent TGW was more diminished than in BYDV infection. Effects of different treatments determined over three years on ergosterol contents in grain were generally similar to effects on disease indices. Grain weight per ear and ear weight of the different treatments of both cultivars largely corresponded with the TGW results. Deoxynivalenol (DON) content in grain of cv. Agent infected with Fusarium spp. was 11–25 times higher compared to the corresponding treatments in cv. Petrus. The DON content in grain of plants of the two cultivars infected with both pathogens was higher than that of plants infected only with Fusarium over the three years.     

小麦黄矮病尖角突变模型及分析

研究了陕西渭北旱塬地区小麦黄矮病发生突变的规律;建立了定量的尖角突变模型;确定了突变区域.根据病害落入的不同区域分析,采取相应防治策略.若病害落入潜在危害区的上限附近,必须采取防治措施,否则将造成不可逆的产量损失,这是由突变模型的性质与黄矮病特性共同决定的.潜在危害区的上限可作为黄矮病的动态防治指标.小麦黄矮病大发生有11～12年的周期,而此周期由2个叠加的周期(5～6年)组成.大发生的周期与太阳黑子活动周期相吻合.     

大麦BYDV抗性的印迹杂交分析

大麦抗黄矮病毒 (BYDV)育种面临的主要困难之一 ,就是常规生物学抗性检测技术不能准确地进行抗性检测和抗性基因筛选。本文在前人的基础上 ,以大麦黄矮病毒 PAV株系和 RPV株系基因组中的特异核酸序列为探针 ,应用斑点印迹杂交分析技术 ,建立了一套简单、快速、有效的 BYDV抗性检测方法和抗性基因 (Yd2 )的筛选方法 ;同时也建立了一套适用于大麦 BYDV抗性检测的较为有效的带毒蚜虫饲养和管理方法。选用了 12个已知抗性和基因型的大麦品种 (系 )进行抗性检测 ,结果证实了这一抗性检测技术体系的可靠性与有效性。     

Insecticidal control of cereal aphids and its impact on the epidemiology of the barley yellow dwarf luteoviruses

Imidacloprid is a seed-applied nitroguanidine insecticide that has both contact and long-lasting systemic properties. Its direct effects on cereal aphid populations and indirect effects on barley yellow dwarf luteovirus (BYDV) incidence were examined in laboratory and field studies. Adult longevity and fecundity of three aphid species caged on various aged, imidacloprid-treated oat or wheat plants was reduced, although the quantitative efficacy of the compound differed among aphid species. The transmission efficiency of BYDV by aphids to imidacloprid-treated plants was lower, relative to nontreated plants, when plants were 10 days old, but similar to nontreated when plants were 24 days old. In three years of field trials using winter wheat and two years using spring oat, aphid populations were reduced significantly in imidacloprid-treated plots relative to nontreated plots. Although the number of alighting alate aphids did not differ significantly between imidacloprid-treated or nontreated plots, the number of apterous aphids remained significantly lower in the treated plots for the majority of the growing season. BYDV epidemics did not develop in spring oat in either of the two years. BYDV epidemics did develop in the fall in the emerging winter wheat crop. Rhopalosiphum maidis was the predominant aphid migrating into the 1991–1992 crop. The incidence of the BYDV-RMV serotype was three times higher in nontreated plots than in imidacloprid-treated plots. In the 1992–1993 and 1994–1995 seasons, R. maidis and R. padi were the predominant aphids migrating into the crop, although R. padi was the predominant colonizing aphid. The incidence of BYDV-RMV was similar in imidacloprid treated and nontreated plots in 1992–1993, but the incidence of the BYDV-PAV serotype was significantly less in the treated plots. In 1994–1995, the incidence of both BYDV-PAV and BYDV-RMV was higher in the nontreated plots than in the imidacloprid-treated plots. Imidacloprid offers several advantages both in terms of its long-lasting systemic activity and its mode of applicaiton. As a seed treatment, the amount of material applied is minimized, there is little waste and the environmental impacts are reduced. The effectiveness of the compound at reducing the fecundity or reproductive rate of several aphid species may be advantageous in controlling secondary spread of viruses. However, the contact properties of the compound, important in repelling aphids or preventing phloem feeding, may be short-lived, thus reducing its effectiveness in preventing primary spread of the virus into the crop, especially under high aphid and inoculum pressure.     

红叶病在燕麦不同生育时期的发生情况及对种子产量的影响

为了明确红叶病在燕麦不同生育时期的发生情况及其对种子产量的影响,对甘肃中部地区的12份田间栽培燕麦材料在分蘖期、拔节期、抽穗期、灌浆期和乳熟期的红叶病发生情况进行调查,并测定了燕麦成熟期的种子产量、有效分蘖数、穗长、小穗数、不育小穗数、穗粒数、穗粒重和千粒重等指标。结果表明:红叶病的发病严重度与燕麦生育时期相关,各供试材料从抽穗期开始发病,随生育期的推移而不断加重,乳熟期发病最为严重,平均严重度在3.26~4.70之间。灌浆期的病害严重度与燕麦种子产量呈极显著负相关(P<0.01,r=-0.781),也与穗粒数、穗粒重、千粒重呈极显著负相关(P<0.01)。在所有供试材料中,Rigdon发病较轻,种子产量最高(3652.78kg/hm^2),综合表现最好;479次之;青永久237最差。