MN品系皮燕麦对E型麦二叉蚜的抗性评价

为了明确MN品系皮燕麦对甘肃流行E型麦二叉蚜的抗性,筛选优异的抗蚜种质资源,在田间3年成株期自然感染蚜量比值法表型抗性鉴定基础上,采用室内苗期人工接蚜、实验种群生命表法测定了12个MN品系皮燕麦对E型麦二叉蚜的抗生性。结果表明,E型麦二叉蚜成蚜在表型中抗品系MN10253上的成蚜寿命和总产蚜量显著低于表型中抗品系MN08243、低抗品系MN09103和中感品系MN09255,产蚜前期显著长于MN08243、MN09103和MN09255;在MN10253上的平均发育历期短于MN08243;在MN10253上的种群趋势指数显著低于MN08243、MN09103和MN09255;在MN10253和MN08243上的内禀增长率rm、周线增长率λ和净增值率R0显著低于MN09255,有翅蚜率显著高于MN09255。说明表型中抗品系MN10253对E型麦二叉蚜种群繁殖具有抑制作用。     

春小麦抗蚜性与麦长管蚜EST活性及GSH活性的关系

为阐明春小麦对蚜虫的抗生性机理及蚜虫对寄主的适应性机制,选用抗蚜性不同的8个春小麦品种（系）为试验材料,利用灌浆期人工接种的方法,研究了小麦抗蚜水平与麦长管蚜无翅型孤雌胎生蚜酯酶（EST）活性及谷胱甘肽转移酶（GSH）活性的关系。结果表明,蚜虫EST活性与春小麦抗蚜水平有关,GSH活性与小麦抗蚜水平无关。穗部及旗叶蚜虫EST活性均与其存活率呈显著负相关,相关系数分别为-0.7047（P=0.04523）和-0.7214（P=0.0380）,与有翅蚜分化率接近显著或显著负相关,相关系数分别为-0.6767（P=0.05911）和-0.7317（P=0.0336）,与仔蚜繁殖率相关不显著。穗部及旗叶上蚜虫GSH活性均与其存活率、有翅蚜分化率及仔蚜繁殖率不相关。     

不同玉米新品种田间抗蚜性比较

在田间自然感虫状态下,采用5点取样法记录玉米蚜虫在不同玉米品种上的危害状况,对21个品种用蚜量比值法进行抗蚜性鉴定,对玉米蚜虫高峰期蚜量比值测定玉米抗蚜性进行可行性分析。结果表明,不同玉米品种抗蚜性差异较大,金西南8号和陇玉1号为高抗品种,桂单203、青青601、珍禾978、周玉913、贝玉10、普玉3号、水金玉8号、云合2号为易感品种。玉米蚜虫天敌数量与玉米蚜虫口数变化规律出现相对一致性,玉米品种的益害比与蚜量比值呈幂函数关系,益害比随蚜量比值的增大而减小。     

蚜虫侵害对不同基因型大豆酶活性及次生代谢物含量的影响

对大豆抗蚜品系P746和感蚜品系交大02-89蚜虫侵害后的过氧化物酶(POD)、过氧化物酶(PPO)、苯丙氨酸解氨酶(PAL)3种酶活性及相关次生代谢物质含量变化与抗蚜性进行相关性分析.结果表明:蚜虫侵害后不同品系之间POD、PPO活性均有升高,与蚜虫的诱导存在相关性,但与抗性基因型不存在显著关联.PAL活性蚜虫侵害前抗虫的P746具有高水平表达,并与感蚜品系存在显著差异;蚜虫侵害诱导后PAL酶活性均有上升,抗蚜品系表现稳定,表明PAL酶活性与大豆的抗蚜性存在明显的相关性.HPLC分析表明蚜虫侵害前后大豆叶片组织内氨基酸、黄酮类物质、生物碱类、酚类等次生代谢产物的含量都发生了明显变化,并且在不同蚜虫侵害时间和抗性基因型之间存在明显差异,表明这类物质与大豆抗蚜性有很大关联.     

3种氧化酶与辣椒抗蚜性的相关性

采用分光光度法和垂直板聚丙烯酰胺凝胶电泳法研究了过氧化物酶(POD)、多酚氧化酶(PPO)、抗坏血酸氧化酶(AsA-POD)与辣椒抗蚜性的相关性。结果表明:抗、感品种叶组织内PPO,POD,AsA-POD活性在受蚜虫侵害后均明显提高,但高抗和抗蚜品种较高感和感蚜品种反应更灵敏,在接虫初期其POD,PPO和AsA-POD活性即上升到一个很高水平,活性增强远远高于高感和感蚜品种,且在受蚜虫侵害后保持稳定的高活性水平;高抗和抗蚜品种叶组织内的POD和PPO同工酶谱带在受蚜虫侵害前后均保持稳定不变,没有新谱带的出现,而高感和感蚜品种在受蚜虫侵害后POD和PPO同工酶谱带均有变化,蚜虫侵害前其POD和PPO同工酶谱带均与高抗和抗蚜品种相同,但受蚜虫侵害后分别减少2条和3条。相关分析表明,辣椒受蚜虫侵害后,叶组织内POD,PPO和AsA-POD活性的增强及POD和PPO同工酶谱的稳定性与辣椒抗蚜性显著相关。      

作物生育阶段对禾谷类蚜虫繁殖的影响

美国大平原北部禾本科作物常发生以下4种蚜虫,麦二叉蚜(GB)、麦长管蚜(EGA)、玉米蚜(CLA)和禾谷缢管蚜(RP)。其中一些由于直接取食危害并传播几种植物病毒病而造成大量减产。由于在大平原北部这4种蚜虫都不能越冬,每年春天虫口都是从南方迁移来的(Kieckhefer等,1974)。夏季,麦二叉蚜、     

用生物学方法研究转双价基因棉抗蚜性

新疆种植的棉花,无论是引进内地的品种还是新疆自育品种均不同程度含有外糖,棉花含外糖的主要原因是蚜虫危害,特别是秋季棉蚜分泌的蜜露污染棉纤维。因此利用转基因育种手段培育抗蚜虫的品种,是解决新疆棉花引起纺织加工粘着的关键。在棉花的抗蚜性研究中,人们多是根据棉花不同品种在田间受害程度来评价棉花的抗虫性,但这种方法随机性较大,有时难免不能代表棉花的真实抗性。为提高鉴定的快速准确性,本文从蚜害指数、蚜虫的体重、排蜜频率与抗蚜性关系进行研究,为解决转基因棉的抗蚜性鉴定和培育抗蚜性品种提供依据。1材料和方法1.1材料实验…     

中国西北地区麦二叉蚜与禾谷缢管蚜对小麦黄矮病传毒能力的分析

为了研究中国西北地区蚜虫对小麦黄矮病的传毒能力,为西北地区防治小麦黄矮病提供参考依据,常温条件下在温室大棚用盆栽小麦做传毒试验,以接种不同数量有毒蚜的小麦苗作为处理,接无毒蚜的小麦苗作为对照.传毒3 d后,在接种麦苗上喷洒药剂彻底杀死蚜虫,充分发病后观察记录小麦黄矮病的发病情况.结果表明,中国西北地区小麦黄矮病的优势介体是麦二叉蚜,但禾谷缢管蚜的传毒能力比以前有所提高.关中地区禾谷缢管蚜的传毒力高于河西地区禾谷缢管蚜的传毒力;三个地区(关中地区、渭北地区、河西地区)麦二叉蚜的传毒力都较高,差别不明显.三个地区两种麦蚜的成蚜传毒力普遍高于其若蚜的传毒力.     

小麦雨锈病蚜传特性的研究

1984年以来,进行了介体蚜虫传毒试验,证明禾谷缢管蚜、麦长管蚜、麦无网长管蚜、麦二叉蚜及玉米蚜均可传毒,传毒发病率分别为74.2％、59.0％、53.6％、31.5％和17.4％。禾谷缢管蚜传毒特性、取食获毒或传毒最短时闻为5分钟,发病率达6.67％。2小时可充分获毒或传毒。蚜虫传毒有间歇现象,持毒期3天,传毒潜伏期65—70分钟。由此可见,小麦雨锈病是由多种蚜虫传播的具有半持久性传毒特性的病毒病。禾谷缢管蚜传毒能力因龄期不同而有所差异,有翅蚜传毒能力最强,无翅成蚜次之,若蚜最低。接种一头带毒蚜虫即可引致发病,接种蚜头数增加,发病率提高,接种7头蚜虫,发病率可达84.2％。     

不同玉米品种抗蚜性室内鉴定

采用环境气候室人工接蚜虫鉴定和累计蚜情指数(I_(aa))评判法,对22份玉米品种进行抗玉米蚜Rhopalosiphum maidis Fitch鉴定。结果表明,不同玉米品种的抗蚜性差异显著,在抗性品种上玉米蚜种群数量为负增长,产生的有翅蚜少;在感虫品种上玉米蚜种群数量急剧增长,并伴随大量有翅蚜产生。I_(aa)值从高抗蚜品种的1.1到高感品种的31.4。高感或感蚜品种9个,占比41%;中抗和抗蚜品种4个,占比18%;高抗品种9个,占比41%。生产上推广种植面积较大的京科968和先玉335等具有中等抗蚜水平,郑单958等高感蚜虫。     

白燕2号EMS突变体的形态鉴定与遗传变异分析

为促进燕麦的遗传改良,采用化学诱变剂甲基磺酸乙酯(Ethyl methane sulfonate,EMS)处理裸燕麦品种“白燕2号”种子,构建燕麦EMS突变体库,对获得的M²代突变体的形态特征进行调查鉴定,估计突变效果并采用内含子切结点引物和长随机引物的PCR技术分析M²代突变体间的遗传多态性。结果显示,所创制的燕麦突变体库的M²代个体间表现出了丰富的遗传变异,变异的总频率为 7.17%。采用15个内含子切接点引物和长随机引物对其中39个突变体株系进行PCR检测,共扩增出99条谱带,其中多态性条带65条,多态性条带比率为65.7％。突变体株系间的遗传相似系数为0.667～0.973,表现出丰富的遗传变异。表明构建的燕麦EMS突变体库具有丰富的突变类型,可用于燕麦重要性状突变体的筛选和候选基因的功能分析。     

燕麦品种(系)的营养品质综合评价

为筛选营养品质优良的燕麦品种(系),对72份燕麦品种(系)的粗纤维、粗蛋白、淀粉和β-葡聚糖含量4个营养品质进行分析,并采用灰色关联度分析方法进行综合评价。结果显示,供试燕麦品种(系)的粗纤维、粗蛋白质、淀粉和β-葡聚糖含量平均分别为1.57%、19.35%、41.98%和4.13%;粗纤维含量的变异系数最大,为32.48%;β-葡聚糖含量变异系数最小,为12.59%。营养品质综合表现较好的品种(系)有px0412、8928-2-2、3121-3、8928-7-5,其等权关联度和加权关联度综合排名位列前4。     

Detection of the lunasin peptide in oats (Avena sativa L)

We report the first discovery of lunasin in oats (Avena sativa L). Lunasin is a novel cancer preventive, anti-inflammatory and cholesterol-reducing peptide originally isolated from soy and later found in cereals (barley, rye, wheat, triticale). Lunasin was detected in oats using LC–MS/MS analysis. The chromatograms and mass spectra of lunasin isolated from five oat genotypes were compared with those of the synthetic lunasin peptide. We measured the lunasin content in harvests of two years and found that all tested oat genotypes contained the lunasin peptide. However, we observed genotype-related fluctuations in the lunasin content. Notably, the middle early oat variety ‘Ivory’ contained the highest and the most stable lunasin level at 0.197 ± 0.01 mg per g of grain in year 2010 and 0.195 ± 0.009 mg per g of grain in 2011. We also characterized the selected oat genotypes by measuring the contents of protein, β-glucans, fat, starch and moisture in the grains. However, we did not find correlation between lunasin and protein, and β-glucan content. Lunasin isolated from oat showed similar to the synthetic lunasin antioxidant effects. The detection of lunasin complements a list of bioactive compounds present in oats and strengthens recommendations to use oat products.     

Development of a standard test for dough-making properties of oat cultivars

Bread is consumed all over the world. However, so far, production of large volume bread is only possible with wheat. Alternatives, such as oats, are less suitable but this is partly due to the lack of knowledge about their functionality for other purposes than porridge, which is their most common use. Existing standard tests for the dough making characteristics of wheat flour are not suitable for oat flour, hampering research to optimize oats for bread-making purposes. We therefore set out to develop a test to evaluate oat in relation to mixing and dough making properties using wheat as a model. It was possible to reproduce the profile of various qualities of wheat flour using mixtures of oat flour and gluten in different proportions. Our standard test was based on a dough system composed of 87.2% oat flour and 12.8% gluten and it presented similar properties to a wheat flour with regard to resistance to extension. This dough system was sensitive and reliable (coefficient of variation lower than 10%) for detecting differences among oat cultivars, and it can be used to screen oat varieties and individual oat components in relation to relevant properties for bread-making purposes.     

燕麦不同磷效率品种苗期对不同磷源的利用研究

为了探究燕麦不同磷效率品种对有机磷的利用能力,选取磷高效品种燕科1号和磷低效品种MARION为供试材料,在土培盆栽条件下,设置植酸态磷(OP)、无机磷(KP)和不施磷(CK)三个磷处理,研究苗期不同磷处理对燕麦不同磷效率品种生物量、磷累积量、根际土壤酸性磷酸酶活性和土壤有效磷含量的影响。结果表明:(1)OP处理下,燕科1号和MARION的生物量较KP处理显著提高,分别提高70.4%、 9.4%;燕科1号的根冠比显著低于MARION。(2)与CK比较,OP处理可显著提高燕麦地上部、全株磷含量,但比KP处理磷含量低;在OP处理下,燕科1号地上部磷含量比MARION提高15.1%,全株磷含量比MARION降低8.6%。(3)与CK比较,OP处理可以提高燕麦根际土壤有效磷含量,但显著低于KP处理;相同处理下,燕科1号根际土壤有效磷含量均低于MARION。(4)两个燕麦品种在不同磷处理下,燕麦根际土壤酸性磷酸酶活性变化不同,燕科1号根际土壤酸性磷酸酶活性在KP和OP处理比CK分别提高35.2%、26.5%,差异均达到显著水平;MARION在KP和OP处理比CK分别降低4.4%、14.1%,OP与CK之间差异显著。磷高效品种燕科1号利用植酸态有机磷能力高于磷低效品种MARION。     

甘南农牧过渡区燕麦田孢囊线虫的发生与分布

为明确孢囊线虫在高寒、高海拔区的发生与分布情况,2015年8月,采用Z字型取样法,对甘南农牧过渡区10个乡镇燕麦田的80份根际土样进行了孢囊线虫调查。80份土样中孢囊线虫平均检出率为87.5%,夏河县的达菱乡、达麦乡、唐嘎尔乡与那吾乡,卓尼县杓哇乡及临潭县冶力关镇土样的检出率均达100%;夏河县王格尔塘镇最低,为60%。海拔高度不同,孢囊线虫的分布不同,在海拔2 501~2 800m的区域土样中,孢囊线虫检出率最高,为100%,在海拔3 101~3 500m区域检出率最低,为58.3%。燕麦田间孢囊线虫密度平均为3.7个·100g~(-1)土,其中卓尼县杓哇乡的密度最高,为14.4个·100g~(-1)土,夏河县王格尔塘镇和临潭县冶力关镇的最低,为1.1个·100g~(-1)土。通过形态学特征鉴定,此区的孢囊线虫为燕麦孢囊线虫(Heterodera avenae)。     

Understanding the role of oat β-glucan in oat-based dough systems

B-glucan is one of the components that differentiate oats from other cereals and that contribute to the health-related value of oats. However, so far oats cannot easily be applied in bread-like products without loss of product quality. Here we have studied how the content and viscosity of oat β-glucan affect the technological properties of oat dough in both a gluten-free and a gluten-containing system. In both systems, increasing the β-glucan concentration resulted in an increase of dough stiffness and in a reduction of dough extensibility. β-glucan negatively impacted the elastic properties that additional wheat gluten conferred to oat dough. This effect was smaller for medium-viscosity β-glucan than for high-viscosity β-glucan. Interestingly, dough made from low β-glucan flour (<2%) had increased gas retention capacity. Overall, the impact of β-glucan on the properties of oat dough systems was governed by concentration and viscosity, with or without additional wheat gluten. Our findings indicate that β-glucan is a key component that determines the rheology of oat-based dough systems and, with that, the technological functionality of oat in dough systems.     

燕麦PRR基因家族鉴定与表达分析

春、夏播燕麦是长日照作物，光周期不敏感燕麦的创制使其在短日照条件下能正常生长发育。PRR基因是光周期途径中重要的昼夜节律调节基因。前期转录组研究表明PRR基因可能与燕麦光周期不敏感性有关。本研究从转录组和全基因组水平对燕麦PRR基因家族进行鉴定、生物信息学分析和表达研究。结果表明，在燕麦转录组和基因组水平分别鉴定到6个和2个PRR基因，均包含REC和CCT结构域；进化分析表明燕麦PRR基因与小麦、大麦、黑麦草和山羊草的亲缘关系较近；燕麦PRR基因启动子区域包含与光响应、生长发育和胁迫相关的顺式作用元件；qRT-PCR分析表明燕麦PRR基因的表达具有节律特征，全生育期过程中AsPRR1和AsPRR2在穗和叶的表达量均呈现由低到高、下降后再升高的双峰趋势，且AsPRR2基因的表达量高于AsPRR1。以上结果说明，AsPRR基因在燕麦光周期途径中发挥负调控作用，其下调表达促进了光周期不敏感性燕麦gp012在短日照条件下开花。本研究为揭示AsPRR基因在燕麦光周期不敏感机制中的作用奠定 了基础。     

燕麦AsSnRK2.7编码蛋白的分子特征及基因表达特异性研究

蔗糖非发酵相关的蛋白激酶2（SnRK2）通过磷酸化在植物胁迫信号转导途径中起关键作用。为发掘并利用燕麦中的 SnRK2基因,本研究基于燕麦转录组数据的注释信息,利用RT-PCR技术从燕麦品种美达中克隆了 AsSnRK2.7基因,借助生物信息学、瞬时表达及实时荧光定量RT-PCR（qRT-PCR）技术分别对该基因或其编码蛋白进行分子特征分析、亚细胞定位和表达特异性研究。结果表明, AsSnRK2.7基因包含一个1 074 bp的开放阅读框,编码357个氨基酸,预测其编码蛋白含有一个STKc_SnRK2结构域和一个PKc_like superfamily结构域,属于SnRK2蛋白激酶家族成员。AsSnRK2.7蛋白一级序列中包含多个SnRK2家族特有的重要功能区。AsSnRK2.7蛋白与水稻的SnRK2蛋白激酶相似性最高,属于Group Ⅰ（SnRK2b）亚家族。亚细胞定位结果显示,AsSnRK2.7蛋白主要定位在细胞核中。qRT-PCR结果显示, AsSnRK2.7基因为组成型表达,在根、茎、叶和穗中的最大表达量分别出现在苗期、分蘖期、抽穗期和灌浆期;此外, AsSnRK2.7基因的表达不被ABA激活,但可以积极应答PEG、盐和低温胁迫。以上结果说明, AsSnRK2.7基因可能作为一个调节因子,通过非依赖ABA途径来调节干旱、盐和低温所引发的信号传导。     

Effects of transglutaminase on the rheological and noodle-making characteristics of oat dough containing vital wheat gluten or egg albumin

Incorporating exogenous proteins into food production is a common practice for improving processing characteristics. In the present study, oat dough containing 15% (w/w, blends of protein-oat flour basis [POB]) vital wheat gluten (VWG) or 15% (w/w, POB) egg albumin (EA) was used to produce noodles with or without gluten (i.e., gluten-free). The rheological and noodle-making characteristics of oat dough containing exogenous proteins and the effects of added transglutaminase (TGase) were examined. The results indicate that the extent of TGase’s modification of the thermomechanical and dynamic rheological characteristics (G′ and G″) is dependent on the source of exogenous proteins in the oat dough. By adding 1.0% (w/w, POB) TGase, the cooking qualities of the resulting noodles (i.e., those containing VWG and EA) were significantly elevated with lower cooking loss; the elasticity of both types of noodles increased. The effects of TGase in different dough systems were analyzed by SDS-PAGE. In oat dough prepared with VWG, TGase was shown to catalyse the cross-linking of both oat protein and gluten protein; however, oat protein acted as the only substrate of TGase in the noodles that had been prepared with EA.