Development of Triticum aestivum-Leymus racemosus ditelosomic substitution line 7Lr#1S（7A） with resistance to wheat scab and its meiotic behavior analysis

Leymus racemosus is highly resistant to wheat scab （Fusarum head bright）. The transfer of scab resistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L, racemosus monosomic addition line with scab resistance was treated by irradiation with 1200 R ^60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1, and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was employed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromosome configuration of the substitution line at MI of PMCs after GISH was 17.50Ⅱ^w ＋ 2.19Ⅱ^w ＋ 0.42Ⅱ^7Lr#1S ＋ 1.08 Ⅰ^7Lr#1S ＋ 0.69 Ⅰ^w. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs. Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at anaphase I and telophase I, including the moving of two telocentric chromosomes to the same pole, lagging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucleus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small fragment translocation induction and telosomic cytological behavior analysis.     

柳树痂囊腔菌的基因组测序和比较基因组分析

【目的】报道柳树痂囊腔菌(Elsinoë murrayae)的全基因组序列,与甜橙痂囊腔菌杨树致病型的基因组进行比较分析,为阐述柳树痂囊腔菌的致病和适应性机制提供参考。【方法】采用Illumina HiSeq 2500 测序仪对柳树痂囊腔菌的全基因组序列进行测序,预测蛋白编码基因,筛选与致病相关的碳水化合物活性酶基因、小分泌蛋白基因和次生代谢产物基因簇。根据痂囊腔属真菌基因的直系同源关系,筛选柳树痂囊腔菌和甜橙痂囊腔菌杨树致病型之间共有特异性的基因和二者之间差异基因,并进行GO富集分析。鉴定柳树痂囊腔菌的交配类型位点,使用特异性引物进行PCR,检测分离株的交配类型。【结果】组装获得了1个20.7 Mb基因组,完整度99%;预测出8 256个蛋白编码基因,其中包括486个碳水化合物活性酶基因,193个小分泌蛋白基因和16个次生代谢产物基因簇 (GenBank登录号:NKHZ00000000)。系统进化和共线性分析显示柳树痂囊腔菌和甜橙痂囊腔菌杨树致病型亲缘关系最近,两者之间具有12个在其他痂囊腔菌中没有的共有特异性基因。两个真菌的比较基因组分析,筛选出752和1 746个差异基因,主要参与碳水化合物代谢和毒素代谢的生物学过程。已有分离株的交配类型均为MAT1-2。【结论】获得柳树病原真菌-柳树痂囊腔菌的基因组,筛选出痂囊腔菌中负责寄主适应性的候选基因,分析了柳树痂囊腔菌交配系统,这可为柳树病害防治和柳树-病原真菌相互作用研究提供关键信息。     

一种γ－亚甲基－γ－丁内酯的烷基取代物防治小麦赤霉病的研究

拟原白头翁素（ｐｒｏｔｏａｎｅｍｏｎｏｉｄ）是毛茛科植物生物活性物质经结构改造后的一类化合物，其中γ－亚甲基－γ－丁内酯的一个烷基取代物暂名为９１０５１２－５，可望发展成为杀菌剂新品种．通过气相色谱和生物测定证明，其化学物及其制剂有效成分和生物活性均较稳定．经室内小麦赤霉病菌毒力测定，抑制５０％的剂量（μｇ／ｍｌ）分生孢子萌发为１８３．６，菌丝生长为２０５．５．同室自然条件下人工接首试验结果，４００μｇ／ｍｌ剂量能很好地控制病情．大田试验初步证明，不论重病田或一般发病四，小麦扬花期一次喷布９１０５１２－５，防效较稳定，且使用剂量较低（３００ｇ／ｈａ），增产作用显著（小麦理论增产７．５～１０．５％）．     

苹果黑星病流行规律研究进展

苹果黑星病在世界各国苹果产区均有发生,严重威胁着苹果产业的可持续发展.本文概述了苹果黑星病发生症状、病原菌形态及生物学特性、病害防治措施,并着重阐述了病害的流行规律.     

苹果黑星病的发生与控制

苹果黑星病(Venturia inaequalis(Cooke)G．Winert)为苹果树主要病害之一,国外属零星发生,国内呈点片分布,是我国13个省的省级补充检疫对象．陕西省最早在凤县发现该病,1986年被确定为省级补充检疫对象．对苹果黑星病地理分布、发生规律、监测方法、控制技术及检疫检验等进行初步探索．     

黄瓜黑星病菌生物学特性及流行规律研究

用不同培养基比较了黄瓜黑星病菌、沈阳菌株（Ｓ－１）和兰州菌株（Ｌ－１）的菌落形态，生长速度及产孢数量。结果表明：它们在果实培养基上生长最快，Ｓ－１生长速度和产孢量比Ｌ－１快而多。并对该病在温室的流行情况作了观测。     

Influence of alloplasm on resistance to wheat scab

Using alloplasmic wheat as test materials, the genetic effect of cytoplasm on wheat scab resistance was studied by three methods including the determination of resistance of explant calli toGibberella zeae toxin, the identification of inoculating single fixed position and the identification of field resistance. The results showed that among “the homonucleo-heterocytoplasmic lines”, resistance of calli toG. zeae toxin was different; the difference of cytoplasmic effect among different nucleoplasm combinations showed certain nucleoplasm interaction relation. Resistance of hybrid F₁ plants of reciprocal cross between alloplasmic line and disease-sensitive wheat variety to wheat scab was of clear difference. Hybrid F₁ of reciprocal cross betweenAe. ventricosa cytoplasmic wheat and disease-sensitive or -resistant wheat variety all exhibited fine resistance effect of alloplasm. Compared with general common wheat variety, most alloplasmic wheats tested have stronger resistance. A few selected lines havingAe. ventricosa cytoplasm have a strong and stable resistance to scab. They can be a finer new resistant source.     

高压溶出过程结疤的分类及危害

高压溶出过程，结疤的产生是洒中避免的。由于热交换器上形成的结疤，使传热效率降低，能耗增加，并影响生产工艺过程的正常进行。了解结疤的分类及危害，对如何采取措施，对结疤进行防治和提高生产过程技术经济指标是十分有意义的。     

氧化铝生产过程结疤溶解的研究

以长城铝业公司全国科技招标项目“氧化铝生产过程结疤高效、快速清理技术”为研究课题,采用不同溶剂进行正交实验对结疤试样进行溶解,研制出一种高效溶剂,并对溶剂使用温度、流速缓蚀剂进行实验,确定了最佳工艺条件。该化学清洗结疤技术与传统处理方法相比,清洗彻底,溶垢率达95％以上;清洗时间缩短,10h即可完成;清洗效果符合《工业设备化学清洗质量标准》。该项技术应用于氧化铝生产,可显提高劳动生产率和经济效益。