优异大麦种质资源的抗性鉴定和评价

1998～1999年,将1997年筛选出的191个农艺性状表现优良的大麦品种进行大麦黄花叶病、大麦白粉病、大麦赤霉病、大麦条纹病及耐盐等抗性的鉴定评价,结果表明,抗及高抗大麦黄花叶病品种60份,抗大麦赤霉病品种59份,高抗大麦条纹病品种89份,抗大麦白粉病品种19份,芽期耐盐品种17份,苗期耐盐品种2份。     

大豆种质资源对灰斑病抗性鉴定评价

近年来,随着大豆品种和气候的变化,灰斑病在黑龙江大豆产区广泛发生,并呈逐年加重的趋势。为了筛选出可在生产或育种中利用的抗病材料,本试验在人工接种条件下,对1073份大豆材料进行抗灰斑病鉴定和评价,结果表明,高抗材料33份、抗病材料291份、中抗材料332份、感病材料381份、高感材料36份,分别占供试材料的3.1%、27.1%、30.9%、35.5%、3.4%。对1、6、7号出现频率较高的优势生理小种鉴定结果是高抗和抗病材料分别是161份、68份、95份,分别占供试材料的15%、6.3%、8.9%。在现行大豆种质资源中,具有比较丰富的抗病资源。     

梨种质对梨火疫病的抗性研究

针对未来梨火疫病侵入我国的风险,采用幼果人工接种鉴定技术,对保存的54份梨种质资源进行梨火疫病抗性评价。通过接种后的症状鉴别、再分离细菌的分子检测,证明有16份种质对梨火疫病表现感病,其中9份为中国种质,7份为引进种质。中国的37份（80．4％）梨种质表现抗梨火疫病,而引进种质中表现抗病的仅有1份（12．5％）。结果初步表明,在中国梨种质中可能存在较丰富的抗梨火疫病资源;东方梨的抗性较西方梨更强;而在梨的地方品种中蕴藏着良好的抗病性。     

大豆种质资源对灰斑病抗性鉴定评价

近年来,随着大豆品种和气候的变化,灰斑病在黑龙江大豆产区广泛发生,并呈逐年加重的趋势.为了筛选出可在生产或育种中利用的抗病材料,本试验在人工接种条件下,对1073份大豆材料进行抗灰斑病鉴定和评价,结果表明,高抗材料33份、抗病材料291份、中抗材料332份、感病材料381份、高感材料36份,分别占供试材料的3.1％、27.1％、30.9％、35.5％、3.4％.对1、6、7号出现频率较高的优势生理小种鉴定结果是高抗和抗病材料分别为161份、68份、95份,分别占供试材料的15％、6.3％、8.9％.在现行大豆种质资源中,具有比较丰富的抗病资源.     

玉米种质资源对纹枯病的抗性鉴定与评价

在人工接种条件下,对国内常用的285份玉米种质资源进行抗纹枯病大田鉴定与评价,未发现免疫材料,抗病材料很少.高抗、抗和中抗材料的比例分别为1.0%、3.2%、13.7%;绝大多数材料属于感病或高感,分别占29.8%、52.3%.株高、主穗位高、主穗位高/株高之比值与病情指数呈负相关,病斑高、病斑高/株高、病斑高/主穗位高之比值与病情指数呈正相关,可以将病斑高度与主穗位高度的比值作为抗性鉴定与评价指标之一.采用带菌麦粒在拔节中后期定位接种,以病斑到达的叶鞘位作为病情和抗性评价体系是较为准确和规范的方法.     

运用BP人工神经网络预测长江中下游梨黑星病发病的研究

提出了运用人工神经网络技术进行梨黑星病预测的新思路,并以梨黑星病发病的主要影响因素,即上年7月的降水量和上年8月的降水量作为训练样本模式提供给网络,按照误差逆传播网络的学习规则对网络进行训练,经过计算机2844次学习后,网络达到预先给定的收敛标准,使网络具备了预测梨树黑星病流行趋势和流行强度的功能。检验结果表明,该方法性能良好,预测准确率高,可望成为果树病早害预测预报的有效辅助手段。     

梨种质资源主要描述标准比较分析

介绍了国内外6个梨种质资源描述标准,并对其主要形态特征与农艺性状描述符进行了归纳整理;分析了各描述符标准的层次结构特征、生物胁迫与非生物胁迫评价内容以及描述符编码方式;指出了制定我国梨相关标准借鉴之处.     

梨树腐烂病抗性种质筛选及相关生理生化特性研究

以46份不同类型梨树种质资源的休眠期枝条为试材,连续2年分析枝条的腐烂病抗病性,并测定枝条韧皮部组织POD、SOD活性,以及总酚含量和组织疏松度;采用酶联免疫分析法(ELISA)测定抗病品种‘秋白’和感病品种‘茌梨’枝干中内源水杨酸(SA)和茉莉酸(JA)的含量;并依据转录组文库中SA和JA合成相关基因(PAL、ICS、AOS和AOC)片段的序列信息,通过实时荧光定量(qRT-PCR)技术分析基因的相对表达量。结果表明:(1)不同类型的梨树种质资源之间腐烂病发病程度表现出较大的差异和多样性,并以秋子梨种类抗性最强,西洋梨抗性最弱。(2)梨树种质资源种类腐烂病发病程度与其枝条韧皮部POD、SOD活性和组织疏松度无显著相关性,与枝条韧皮部总酚含量呈显著正相关关系。(3)在病菌接种情况下,抗病品种‘秋白’枝干中SA和JA含量显著上升,同时其相关合成酶基因PAL和AOS表达量也显著升高,而感病品种‘茌梨’枝干中SA和JA含量变化不明显,相关合成酶基因PAL、ICS、AOS和AOC的表达量则显著下降。研究发现,梨树不同类型种质的腐烂病抗性有明显差异,其发病程度与枝条韧皮部总酚含量呈显著正相关关系;内源SA和JA可能参与抗病梨树种质资源对腐烂病的抵御过程。     

梨砧木种质资源的SSR遗传多样性分析

用9对SSR特异性引物对74份梨砧木种质资源进行遗传多样性分析,结果表明：9对SSR引物扩增得到57个等位基因,平均6.33个,可以区分除K11、K12、杜梨-13和杜梨-15以外的70份梨资源样本。聚类分析结果显示,74份样本的相似系数的变化范围为0.41~1.00,表现出较高的遗传多样性。供试品种在相似系数0.67处被分为7大类群,与品种的系谱来源和地理分布基本吻合。     

梨黑星菌粗毒素对抗病和感病梨离体叶片生理特性的影响

以不同抗病性梨品种为材料,研究了梨黑星菌粗毒素对梨离体叶片的过氧化物酶(POD)活性、苯丙氨酸解氨酶(PAL)活性、丙二醛(MDA)含量、细胞膜相对透性以及叶绿素含量变化的影响.研究表明,毒素接种后抗病和感病品种叶片的POD和PAL活性、MDA含量和相对电导率均呈上升趋势,其间会有1个或2个峰值出现,且抗病品种叶片的POD和PAL活性高于感病品种,而细胞内MDA含量和相对电导率增加比率低于感病品种;同时,毒素使梨离体叶片的叶绿素、类胡萝卜素含量下降,且感病品种的下降幅度大于抗病品种.总之,梨离体叶片POD和PAL的活性变化与梨品种抗病性呈正相关,叶片MDA含量和相对电导率变化与梨品种抗病性呈负相关,抗病品种离体叶片对毒素的毒害有更强的抵抗力.     

Phenotypic Reaction and Genetic Analysis Using AFLP-derived SCARs for Resistance to Apple Scab

Six sequence‐characterized amplified region (SCAR) markers linked to the apple scab resistance gene Vf were evaluated for their utility in marker‐assisted selection (MAS) in apple breeding. Of the six SCARs used in this study, ACS‐6 was located left of the Vf gene, ACS‐7 and ACS‐9 co‐segregated with Vf, and ACS‐8, ACS‐4, ACS‐5 were located right of the Vf gene. Three families derived from crosses between scab‐resistant and scab‐susceptible cultivars, including ‘Liberty’ × ‘Deljub’, ‘Liberty’ × ‘Delcorf’, and ‘Florina’ בDelcorf’, previously screened for scab resistance following greenhouse inoculation with the fungal pathogen Venturia inaequalis, were genotyped and compared with phenotypic reactions to scab infection in the field. For each family, a subset progeny of 30 seedlings (propagated onto Malling 9 rootstock and of 7 years old) was selected based on fungal sporulation according to the following scheme. Ten seedlings with no visible scab sporulation on leaves were given phenotypic scores of 0 (deemed resistant); 10 seedlings with moderate scab sporulation were given phenotypic scores of 1.0 (deemed moderately resistant); and 10 seedlings with heavy sporulation were given phenotypic scores of 2.0 (deemed susceptible). DNA was isolated from leaf tissue collected from all 90 seedlings, parents and Malus floribunda 821, the original source of the Vf gene, and screened with all six SCARs. All six SCARs were present in the two scab‐resistant parents, ‘Liberty’ and ‘Florina’, and M. floribunda 821; while, the two scab‐susceptible parents, ‘Deljub’ and ‘Delcorf’, lacked all SCARs. All SCARs were either present or absent in varying numbers of seedlings in each progeny with phenotypic ratings of either 0 (resistant) or 1.0 (moderately resistant); while all seedlings with phenotypic ratings of 2.0 (susceptible) lacked all SCARs. The inconsistencies between phenotypic scab ratings and SCAR marker data are discussed.     

小麦对赤霉病抗性不同品种的SOD活性

本研究对9个赤霉病抗性不同小麦品种采用赤霉病菌分生孢子悬浮液以单花针注法进行了田间和温室抗病性鉴定;测定了各品种的胚性愈伤组织和盛花期麦穗分别经赤霉病菌毒素和分生孢子接种前后SOD活性的变化。结果表明,各品种SOD活性与其对赤霉病抗性呈极显著的正相关。接种后寄主的SOD活性均有提高,抗病品种比感病品种提高幅度大,且有新的同工酶带出现。抗病品种望水白比感病品种Alondra“S”多出两条SOD同工酶谱带。SOD在小麦抗赤霉病上可能起积极作用,其活性有可能作为鉴定小麦抗赤霉病的一种生理生化指标。     

Penetration Behaviour of Venturia nashicola,Associated with Hydrogen Peroxide Generation,in Asian and European Pear Leaves

The penetration behaviour of the pathogen Venturia nashicola, which causes scab disease in Asian pears, was studied at the ultrastructural and cytochemical levels in host and non‐host leaves. We show, for the first time, that before V. nashicola penetrated the cuticle of the epidermis of the pear leaf, the appressorial bottom of the pathogen invaginated to form a cavity that contains electron‐dense material. The leaf cuticle beneath the cavity also became highly electron dense following penetration by V. nashicola. The location of these electron‐dense materials at the sites of penetration of the pathogen into plant cell walls suggests that they might be related to enzymes capable of degrading cell walls and that the cavities might be needed for successful penetration of leaves by V. nashicola. The generation of hydrogen peroxide (H₂O₂) was observed in penetration‐related infection structures of V. nashicola, such as appressorial bottoms, infection sacs, penetration pegs and necks of subcuticular hyphae regardless of whether the interaction of V. nashicola with pear plants was compatible or incompatible. Nonetheless, more H₂O₂ was generated at the sites of the structures in scab‐inoculated susceptible leaves than that in scab‐inoculated resistant ones. Furthermore, the decrease in the level of H₂O₂ generation following treatment with the antioxidant ascorbic acid partially prevented the penetration of the cuticle. Therefore, the generation of H₂O₂ from the penetration‐related structures might be a pathogenicity factor that contributes to strengthening the penetration peg of V. nashicola.     

梨优异种质早酥及利用

早酥是中国农业科学院果树研究所以苹果梨为母本,身不知为父本,通过有性杂交手段创制的早熟、早果、优质、适应性极强的优异梨种质,该种质在生产中作为早熟梨在多个地方推广栽培,创造了很好的经济效益,本文对早酥梨的生产应用、遗传特性及育种价值进行了综述,为该种质的推广和利用提供借鉴。     

两种统计方法在玉米种质综合评价中的应用

以玉米为研究对象,运用灰关联分析和因子分析对10份玉米种质的12个农艺性状进行综合评价,探讨这两种统计分析方法在玉米种质综合评价上的应用效果。结果表明,综合评价较好的2个品种分别是Suwan1和下层云优78,两种分析方法的结果基本一致,从而提高了综合评价的可靠性和科学性。     

利用细胞工程技术筛选小麦抗病新种质的研究

在利用细胞工程技术筛选小麦抗根腐病和赤霉病突变体研究工作的基础上,将已获得的突变株继续进行多年多点的抗病鉴定,对突变株后代的抗病性进行测定,并对农艺性状作详细的观察。结果表明,抗病突变株不论是同一年份在不同鉴定点上,还是在同一鉴定点上多年重复鉴定,都表现有较强的抗根腐病菌和赤霉病菌侵染的能力,突变株的抗病性不因代数的增加而发生变化。已从中选出４个对根腐病和赤霉病抗性强而稳定、农艺性状亦较好的新种质,提供给一些育种单位利用。     

梨品种资源果实轮纹病抗性的评价

采用田间人工接种的方法,2009-2010年连续两年对保存于国家梨种质资源更新圃的182个品种进行果实轮纹病抗性评价。结果表明：砂梨、白梨、秋子梨、种间杂交梨、西洋梨和新疆梨的两年平均发病率分别为6.15%、7.20%、7.43%、12.66%、17.00%、18.93%,梨品种间对轮纹病抗性存在差异,不同条件下多数品种轮纹病发病率有差异。依据两年平均发病率进行抗性评价分级,72个品种为高抗、63个品种为抗、25个品种为中抗、14个品种为低抗、8个品种为不抗。     

Breeding for the Digenic Apple Resistance to Scab

The results of the apple breeding for digenic resistance to scab (1979–2000), which is more long-term than the monogenic breeding, have been reviewed. The hybrid seeds obtained from the reciprocal crossing between the V _f and V _m resistance gene donors served as the original material. The seed progeny yielded by backcrosses between these hybrids and the susceptible cultivars were examined (age—first true leaves) using inoculation in a greenhouse. The following criteria were proposed for breeding parental forms and the cultivars of the V _f v _f V _m v _m genotype: (1) phenotype segregation in the progeny of three resistant: one susceptible seedling and (2) the presence in the progeny of two types of resistant seedlings: those with the class 1 resistance (points and spots—hypersensitivity) typical of the V _m gene and those with the class 2–3 resistance (chlorotic and necrotic spots) typical of the V _f gene.