花生抗黄曲霉大果种质的创制与鉴定

培育和种植抗黄曲霉品种是防控花生黄曲霉毒素污染最为经济有效的途径,而黄曲霉抗性与高产的矛盾一直是花生抗黄曲霉育种的障碍.本研究以抗黄曲霉花生种质J11与高产品种中花16为亲本构建的重组自交系群体(Recombined inbreed lines,RILs)为材料,进行黄曲霉侵染和产毒抗性鉴定,探讨抗性与高产(大果)性状...     

花生种子受黄曲霉菌侵染后若干生化成份的变化及其与抗性的关系

花生种子人工接种黄曲霉菌（Aspergillus flavus Link)侵染的生化测试结果表明，接种前后花生种子的过氧化物酶（POX），多酚氧化酶（PPO）和苯丙氨酸解氨酶（PAL）活性以及木质素含量等均发生显著变化。接种前POX活性与侵染率呈极显著负相关，接种后POX活性随感染天数增加而增加，感病品种比抗病品种POX活性增幅大。接种后1－3d抗病品种PPO和PAL活性达峰值，而感病品种3－6d达峰值，接种后第7d木质素含量与感染率呈显著负相关（r=-0.7406），木质素含量的变化与POX活性变化呈显著正相关。     

Field evaluation of resistance to aflatoxin accumulation in maize inbred lines in Kenya and South Africa

Aflatoxin, a carcinogenic toxin, is produced mainly by Aspergillus flavus and Aspergillus parasiticus. Contamination of maize (Zea mays L.) grain by these fungi occurs before harvest, and the easiest strategy to prevent this is to develop/use maize varieties resistant to Aspergillus spp. and aflatoxin accumulation. The objective of this investigation was to identify potential sources of resistance among 23 maize inbred lines (13 obtained from the MAIZE Competitive Grants Initiative, International Maize and Wheat Improvement Centre and 10 from Agricultural Research Council, South Africa). The inbred lines were planted in a randomized complete-block design at two locations each in Kenya and South Africa. Maize ears were inoculated at silking with three toxigenic strains of A. flavus. The inoculated ears in each plot were harvested at 12–18% moisture, dried, and visually assessed for Aspergillus ear rot (AER). Aflatoxin concentration in the kernels was determined using liquid chromatography–tandem mass spectrometry. Significant variation for both AER and aflatoxin concentration existed among the inbred lines at both locations in Kenya and one location in South Africa. Combined analysis revealed a significant (p < 0.001) lines × locations interaction for both AER and aflatoxin concentration. Higher incidences of AER (0–86.0%) and aflatoxin concentration (0.21–6.51 µg/kg) were recorded at Kiboko in Kenya than at the other three locations. A stronger genetic correlation (r_G = 0.936, p < 0.0001) between the AER and aflatoxin concentration was recorded in Potchefstroom than at the other three locations. Repeatability of aflatoxin concentration was high at Kiboko (0.87) and Potchefstroom in South Africa (0.74). Three inbred lines, CML247, CML444, and CML495, emerged as potentially useful sources of resistance to AER and aflatoxin accumulation as they showed low levels of aflatoxin contamination in both localities in Kenya and in South Africa.     

花生种子苯丙氨酸解氨酶活性与抗黄曲霉侵染的关系

研究了花生种子苯丙氨酸解氨酶 (PAL)活性的变化与抗黄曲霉的关系。结果花生种子接种黄曲霉前苯丙氨酸解氨酶活性与抗性无关。接种黄曲霉后 ,抗病品种与感病品种中苯丙氨酸解氨酶活性的变化不同。抗病品种接种后 1d苯丙氨酸解氨酶被诱导激活 ,PAL活性达到高峰 ,而感病品种反应缓慢 ,需要 4～ 5d酶活性才达到高峰     

High variation in frequency of infection by endophytes in cultivars of meadow fescue in Finland

Systemic and asymptomatic Neotyphodium fungal endophytes infect numerous species of the Poaceae. The frequencies of Neotyphodium endophyte infection in Finland were investigated among and within seven Nordic cultivars of meadow fescue, Schedonorus pratensis (Huds.) P. Beauv., which is a widely grown pasture and forage grass species in Scandinavia. The cultivars were Kasper, Salten, Antti, Fure, Ilmari, Inkeri and Kalevi. Frequencies of infection of cultivars varied from endophyte-free cultivar Fure to highly infected cultivar Inkeri [mean (standard deviation of mean) of 0·95 (0·023)]. Mean frequencies of infection of three cultivars remained lower than 0·10, and two of the cultivars, Kasper and Salten, were intermediately infected. In most of the cultivars, frequencies of infection varied only slightly among seed lots. In cultivar Kasper, however, the frequency of endophyte infection was highly variable (0–0·96) among the 45 seed lots examined. The relative importance of cultivar, seed lot and infection by Neotyphodium endophyte to the aphid Rhopalosiphum padi L. was studied experimentally, using both endophyte-free and endophyte-infected plants of four seed lots of the two intermediately infected cultivars. Endophyte infection increased plant resistance to R. padi , overriding the influences of seed lot and cultivar. It is proposed that variation caused by endophyte infections in cultivars of meadow fescue should be taken into account in assessing plant breeding programmes in Europe.     

甘薯抗薯瘟病的水杨酸与活性氧的代谢变化

研究不同抗性甘薯品种受薯瘟病菌侵染后水杨酸(SA)和活性氧(ROS)的代谢变化.结果表明,感染薯瘟病菌12 h后甘薯叶片中SA含量增加,增加量与品种抗性呈正相关;接菌后过氧化氢(H2O2)含量增加,过氧化氢酶(CAT)活性下降,抗病品种变化幅度大于感病品种;接菌后抗病品种提高了与产生H2O2相关的酶过氧化物酶(POD)、超氧化物歧化酶(SOD)的活性,而感病品种与此相反,积累H2O2的能力下降,影响系统获得抗性(SAR)的建立.     

花生种质资源对黄曲霉菌侵染和产毒的抗性鉴定

对不同种子成分的花生种质资源对黄曲霉菌侵染和产毒的抗性进行了鉴定,结果表明,高含油量、高蛋白质含量和高油酸含量资源对黄曲霉菌侵染和产毒的抗性较差.通过对抗黄曲霉侵染和产毒能力不同的花生种质资源的种子成分的分析表明,高抗黄曲霉菌侵染和产毒资源的亚油酸含量较高.相关分析表明,不同花生品种对黄曲霉菌的侵染抗性与种子大小和油酸含量呈显著负相关,与出仁率和亚油酸含量呈显著正相关;不同花生品种对黄曲霉菌产毒的抗性与含油量呈显著负相关.通过鉴定和筛选,发掘出2份优质抗病资源.     

花生抗黄曲霉菌侵染和产毒机制研究进展

黄曲霉菌（Aspergillus flavus L.）侵染花生导致黄曲霉毒素（Aflatoxin）污染是影响花生食用安全性和限制花生产业发展的重要因素,其污染抗性分为抗侵染和抗产毒两种类型。抗性机制主要包括形态机制、生理机制和分子机制。种皮中决定花生抗侵染的主要因素为蜡质层厚度、栅栏细胞排列密集程度及有无裂纹等特征。种子中单宁酸、胰蛋白酶抑制剂、白藜芦醇等与花生抵抗黄曲霉菌侵染及毒素合成有关。病程相关蛋白基因、转录因子基因、脂氧合酶基因等均参与了花生抵抗黄曲霉菌侵染的过程。随着生物技术的迅猛发展,将来可利用全基因关联分析和多组学结合的方法,从基因调控网络水平上开展花生黄曲霉抗性研究,在更深层次上阐明花生黄曲霉抗性机制。     

玉米南方锈病研究进展及抗病育种策略

玉米南方锈病在我国玉米生产上的危害日益加剧,培育抗病玉米品种是控制该病害的有效途径,培育抗病品种关键在于多生态区抗源种质的筛选、育种亲本抗病性快速改良纯化及鉴定。本文分析玉米南方锈病在国内外的发生与危害、侵染源及传播特性、病菌侵染玉米后的病症特点,阐述玉米抗南方锈病种质资源的挖掘与筛选,探讨玉米抗南方锈病基因研究,提出抗病育种策略。     

我国芝麻种质资源抗茎点枯病鉴定

1987—1990年,以国内外芝麻种质资源3108份为材料,通过田间自然诱发和人工接种,进行抗茎点枯病鉴定。结果表明,无免疫品种,高抗品种32份,高耐品种112份,抗病品种885份,感病品种1756份,高感品种323份。江淮一年两熟夏芝麻区的抗源材料最多,其次为华北春芝麻区。国外资源中抗性材料所占比例较国内高。单秆型芝麻较分枝型芝麻的抗性强。白芝麻抗源材料最多,其次为黄芝麻、褐芝麻,而灰芝麻、黑芝麻抗性最差。     

Recent Advances in Development of Herbicide Resistant Transgenic Hybrid Rice in China

In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63, R752, T461, R402, D68 and E32 were transformed directly with herbicide resistance genes, in which D68 and E32 are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63, Teqing, Milyang 46, R402 and 9311, in which 9311 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei'ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei'ai 64S/Bar 9311. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc.     

花生荚壳抗黄曲霉菌侵染的鉴定方法研究及抗性种质发掘

        黄曲霉毒素污染是影响花生食用安全性和制约产业发展的重要因素。荚壳是花生抵御黄曲霉菌侵染的第一道防线,为建立花生荚壳抗黄曲霉侵染的鉴定方法,本研究利用强侵染黄曲霉菌AF2202接种花生荚果,通过对不同接种菌浓度和培养时间的比较分析,发现接种浓度为2 ×106孢子/mL、培养7d的组合方案可以有效区分花生荚壳对黄曲霉菌侵染的抗性。利用所建立的鉴定方法对276份遗传变异丰富的花生核心种质材料进行接种鉴定,进一步证明了这一方法鉴定花生荚壳抗性的有效性和实用性,初步发掘出2份具有荚壳抗性的特异花生种质。     

陕西省2015-2016年小麦区试品种（系）的抗白粉病分析

为了明确陕西省2015-2016年小麦区试品种(系)的白粉病抗性,以陕西省各地采集的白粉菌混合菌系作菌源,分别在苗期采用人工接种、成株期诱发发病的方法对228份陕西省区试品种(系)和32份已知抗白粉病基因载体品种(系)进行抗性鉴定.结果表明,Pm4a、Pm4b、Pm13、Pm17、Pm18、Pm19、Pm21、Pm24、Pm30、Pm2+6、Pm2+Mld、Pm2+6+?、Pm5+6、Pm“XBD”基因对小麦白粉病表现免疫或高抗;Pm3a、Pm3b、Pm6、Pm4+8、Pm4b+Mli、Pm4+2+?基因对小麦白粉病表现出较弱的抗性,其他基因对供试菌系没有抗病性.228份区试品种(系)中,大多数对白粉病表现为感病,仅有14份在苗期和成株期均表现抗病,33份仅在成株期表现抗病,分别占区试品种(系)总数的6.14％和14.47％.     

小麦抗赤霉病鉴定及其抗病基因的检测

小麦赤霉病是由镰刀菌和禾谷镰孢菌引起的小麦真菌病害,严重影响小麦的产量与品质。为了筛选适合黄淮麦区利用的抗病品种资源,于2017-2018年度利用单花滴注对107份黄淮麦区小麦资源进行田间赤霉病抗性鉴定;同时利用与 Fhb1、 Fhb2、 Fhb4和 Fhb5共4个与抗赤霉病相关QTL紧密连锁的8个分子标记对供试小麦材料进行了检测。经鉴定,扬富麦101表现为抗赤霉病(R),宁麦13、宁麦资119、扬麦16等12个品种表现为中抗赤霉病(MR);分子标记检测发现,这些抗赤霉病品种携带1个或多个抗赤霉病QTL位点,其中 Fhb1基因及其基因组合效应最为明显, Fhb1可以作为主要抗性基因应用于小麦赤霉病抗性育种。     

大豆抗腐霉根腐病的生理差异研究

腐霉根腐病是大豆主要的土传病害,为揭示抗感病大豆品种的生理差异,对不同抗性品种在腐霉病原菌侵染下的大豆下胚轴中丙二醛、苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、可溶性糖、脯氨酸含量的变化进行测定。结果表明:腐霉菌侵染后,抗病大豆品种下胚轴的丙二醛含量增加不十分明显;可溶性糖含量都是正向增加,苯丙氨酸解氨酶活性,过氧化物酶活性,脯氨酸含量在不同时段都有所增加且抗病品种明显高于感病品种。而感病品种在腐霉菌侵染条件下,大豆下胚轴中丙二醛含量累积较高,可溶性糖在某一时段内有所减少,苯丙氨酸解氨酶活性、过氧化物酶活性,脯氨酸含量增加幅度小于抗病品种,表明抗病品种具有较强的生理生化调节能力。     

小麦品种在西藏的抗条锈性变异监测分析

为了解不同小麦品种在西藏的抗锈性表现,于2009-2011年在西藏林芝西藏农牧学院实习农场,对来自全国小麦条锈病菌变异观察圃的46份已知抗性基因小麦品种、45份生产及后备品种和由西藏农牧学院保存的26份西藏小麦种质资源(包括生产品种、引进抗源品种及区试材料)进行了田间自然诱发抗条锈病鉴定。结果表明,在小麦条锈病菌变异观察圃中,46份已知基因品种中33份表现为抗病,3份表现为感病,10份抗性不稳定;45份生产及后备品种中20份表现为抗病,12份表现为感病,13份抗性不稳定;26份西藏种质中,22份表现为抗病,3份表现为感病,1份抗性不稳定。调查表明,大部分材料表现出较稳定的抗病性,但目前在西藏高原麦作区实际生产中应用却较少。为减轻小麦条锈病的发生危害,应进一步加强抗病品种的选育和推广。     

不同花生品种对花生果腐病的抗性鉴定

采用自然病圃鉴定法，对76个花生品种（系）进行了花生果腐病抗性评价，以期为抗病育种及田间病害防 治提供理论依据和抗性材料。结果表明，不同花生品种间对花生果腐病的抗性存在着显著差异，供试76份花生品 种（系）中未发现对果腐病免疫的品种，获得高抗品种2个，抗病品种7个，中抗品种12个，感病品种21个，高感品种 33个。聚类分析结果表明，分支I中的9个品种（尤其是花育9115）抗性较好，可进一步加以利用。花生对果腐病的 抗感性与荚果鲜重之间不存在显著相关。     

山东省棉花中熟品种区域试验菏泽点2012年结果分析

以山东省中熟棉花品种区域试验中常规组和杂交组棉花品种（系）为材料进行生育期、农艺性状、丰产性和抗病性比较试验。结果表明：常规组中CQ1215生育期123d,单株果枝数12．4个,单株结铃数20．10个,籽棉总产居第2位,皮棉总产和霜前皮棉产量均居第l位,分别达4813．5、2175．8和2037．0kg/hm2,增产显著,霜前籽棉产量表现也较好;CQ1216、CQ1212、CQ1207、CQ1214、CQ1213、CQ1217和CQ1209等也表现较好。杂交组中以ZQ1223表现最好,生育期124d,单株果枝数13．2个,单株结铃数25．3个,籽棉总产、霜前籽棉产量、皮棉总产和霜前皮棉产量均居第l位,分别比对照增产11．36％、12．46％、15．05％和12．70％。表现较好的有ZQ1233、ZQ1232、ZQ1222、ZQ1230和ZQ1225等。调查显示,所有参试品种均高抗枯萎病,抗或耐黄萎病。     

小麦PR-1、PR-2、PR-5基因的白粉菌和水杨酸诱导表达分析及白粉病抗性研究

病程相关蛋白基因PR-1、PR-2和PR-5是植物抗病基因介导的抗病反应和系统获得抗性(systemic acquired resistance,SAR)中的标志基因.为了研究病程相关蛋白基因和水杨酸在小麦(Triticum aestivum L.)抗白粉病反应中所起的作用,以抗白粉病和感白粉病小麦品系为材料,在白粉病菌(Blumeria graminis f.sp.tritici,Bgt)诱导不同时间,或水杨酸处理不同时间后,用半定量RT-PCR技术检测了小麦叶片中PR-1、PR-2和PR-5基因的表达变化.结果表明,白粉病菌的侵染激活和显著增强了病程相关蛋白基因PR-1、PR-2和PR-5在周麦18中的转录.与感病品系相比,PR-1和PR-5在抗病品系中转录激活得更快、更强.水杨酸处理显著激活了PR-1和PR-5的转录,但对PR-2的转录影响不大.白粉病菌和水杨酸均能显著激活和增强PR-1和PR-5的表达,但白粉病菌的作用更强,说明PR-1和PR-5基因在小麦抗白粉病反应中起重要作用.PR-1和PR-5可以作为小麦SAR的标志基因.水杨酸处理后周麦18和中国春的白粉病抗性得到提高,提示水杨酸在小麦抗白粉病信号传导途径中起一定作用. 激活和显著增强了病程相关蛋白基因PR-1、PR-2和PR-5在周麦18中的转录.与感病品系相比,PR-1和PR-5在抗病品系中转录激活得更快、更强.水杨酸处理显著激活了PR-1和PR-5的转录,但对PR-2的转录影响不大.白粉病菌和水杨酸均能显著激活和增强PR-1和PR-5的表达,但白粉病菌的作用更强,说明PR-1和PR-5基因在小麦抗白粉病反应中起重要作用.PR-1和PR-5可以作为小麦SAR的标志基因.水杨酸处理后周麦18和中国春的白粉病抗性得到提高,提示水杨酸在小麦抗白粉病 号传导途径中起一定作用. 激活和显著增强了病程相关蛋白基因PR-1、PR-2和PR-5在周麦18中的转录.与感病品系相比,PR-1和PR-5在抗病品系中转录     

The Effect of Long Term Storage on Bacterial Soft Rot Resistance in Potato

Bacterial soft rot is a serious disease in potato (Solanum tuberosum L.), causing rapid tuber tissue maceration and, consequently, marketable yield loss. Soft rot bacteria, including Pectobacterium carotovorum subsp. carotovorum (Pbc), are favored by moist conditions, which are prevalent in large potato storage facilities. However, although most potatoes in North America are stored before use, there are no published surveys of soft rot resistance in cultivars exposed to long-term storage conditions. Thus, we tested 65 cultivars and 13 breeding lines for soft rot resistance after 6 months of storage. There was a significant effect of cultivar and production environment on soft rot resistance score. During 6 months of storage, tuber soft rot resistance in resistant clones did not change, while it changed in susceptible clones. The three most resistant cultivars to soft rot were Freedom Russet, Anett, and Alaska Red Eye.