向日葵抗列当遗传研究

从吉林省境内采集的向日葵材料中鉴定筛选出了对列当抗感性无分离的亲本,配制了3个抗列当( P1 ) ×感列当( P2 )的组合。通过对3个组合F1、F2 和BC1 ( P2 )的列当接种鉴定,后代的表现型符合一对显性等位基因 控制的分离比率。根据抗列当的遗传规律,提出了感列当杂交种和自交系的抗性改良方法。     

向日葵品种抗向日葵螟鉴定及抗性评价方法

利用田间自然抗虫鉴定法连续3年在内蒙古巴彦淖尔市对56个向日葵品种进行了抗向日葵螟鉴定,结果表明,17个油葵品种中除P50表现为中抗（籽粒被害率为6.7%）,其余品种全部表现为高抗,籽粒被害率均在0～2.5%;而39个食葵品种中仅新食葵7号表现为高抗（籽粒被害率为1.9%）,其余多表现为感虫或高感,籽粒被害率在5.8%～54.1%。进一步利用黑色素鉴定法对所有品种进行了室内检测,其结果与田间抗虫鉴定结果基本吻合。由此认为：在进行田间自然抗虫鉴定时,宜根据田间向日葵螟成虫种群动态选择适宜的播期,使向日葵的开花期与向日葵螟成虫发生盛期尽量吻合,以提高害虫对向日葵的选择压力和鉴定结果的科学性,同时避免出现播期避害现象,干扰鉴定结果的准确性。     

Interactions of sunflower (Helianthus annuus) and sunflower broomrape (Orobanche cumana) as affected by sowing date,resource supply and infestation level

The holoparasitic weed Orobanche cumana (sunflower broomrape) constrains sunflower (Helianthus annuus) production in many countries. The development of efficient control strategies requires an understanding of the processes underlying the complex environment–host–parasite interrelations. Growth and development of O. cumana and sunflower were quantified under field conditions in southeastern Romania. Sunflower hybrid Florom 350 was sown at two dates, in plots infested with 0, 50, 200 and 1600 viable O. cumana seeds kg⁻¹ dry soil, under low-input (rainfed, low nitrogen supply) and high-input (irrigated, high nitrogen supply) conditions. Sunflower shoot biomass reached peak values of 760–1287 g m⁻² between the end of anthesis and physiological maturity. Seed yield varied from 221 to 446 g m⁻². Sunflower biomass and yield were affected by all experimental factors. Seed yield responded positively to delaying sowing from early April to late May as well as to irrigation and fertilisation, and negatively to O. cumana infestation. Yield reductions, which were a product of reduced seed number and size, amounted to 13%, 25% and 37% at parasite seed densities of 50, 200 and 1600 viable seeds kg⁻¹ soil, respectively. Maximum O. cumana attachment numbers, recorded in late-sown high-input crops in 2004, ranged from 11 m⁻² in plots with 50 parasite seeds kg⁻¹ soil to 188 m⁻² with 1600 seeds kg⁻¹ soil. Parasite attachment number was a function of crop sowing date, water and nutrient supply, seedbank density, and sunflower biomass and root length density, via mechanisms of parasite seed stimulation, host carrying capacity and intraspecific competition. Delayed sowing and improved water and nitrogen supply were associated with increases in parasite number that neutralised yield-boosting effects of irrigation and fertilisation at the highest infestation level. Sunflower shoot biomass was significantly reduced by O. cumana infection, with reductions affecting organs in the order head > stem > leaves. Most of the discrepancy between infected and non-infected plants was accounted for by O. cumana biomass. Parasites mainly acted as an extra sink for assimilates during sunflower generative growth and impaired host photosynthesis to a much lesser degree. Results suggest that similar mechanisms govern infection level and host–parasite biomass partitioning across different Orobanche–host systems.     

利用向日葵野生种构建抗黑斑病遗传群体和选育自交系

以向日葵优良群体为母本,具有耐黑斑病基因的向日葵野生种为父本进行杂交,利用幼胚培养技术对远缘杂交后代进行胚拯救,从而获得具有耐黑斑病基因的5个遗传群体.在这些群体中,F1发病株率比CK降低96.5%、F2发病株率比CK降低86.6%.在抗黑斑病遗传群体中,运用轮回选择结合抗黑斑病鉴定,选育出6个抗黑斑病自交系,实验室接种发病率比CK降低96.4%,田间自然发病率仅为1%.     

A participatory farming system approach for sustainable broomrape (Orobanche spp.) management in the Near East and North Africa

Broomrapes (Orobanche spp.) are aggressive and damaging parasitic weeds which have a tremendous impact on agriculture in East Africa, the Mediterranean region and the Middle East. Despite the availability of technologies to control broomrapes in economically important crops, Orobanche infestation continues to increase, threatening the livelihoods of millions of farmers. Many of the technologies developed have not been effectively disseminated and there has been little or zero adoption by farmers—who continue to use ineffective management practices that exacerbate the problem. The adaptation and dissemination of appropriate management practices are major priorities in broomrape control. However, such work must take into consideration the specific socio-economic characteristics of individual farming systems. Orobanche is a community threat and effective management requires a community-based integrated management approach. Recognizing the central role of farmers in parasitic weed management, a technical cooperation project (TCP) involving FAO, ICARDA and seven countries in the Near East and North Africa (NENA) region was implemented to improve the dissemination of knowledge and skills by using a farmer field school approach: a form of education that uses experiential learning methods to build farmers’ expertise. This paper reviews conventional Orobanche research and development approaches, and highlights weaknesses in the management of the parasitic weed using these approaches as opposed to participatory approaches. The benefits and challenges of participatory farming system approaches in relation to integrated broomrape management (IBM) are also discussed. Lessons learned from achieving community ownership of, and institutional support for, IBM could be applied to other sectors (e.g. public health) in which there is a need for institutional learning and reform. Recommendations are made that include regional collaboration within the framework of a proposed Near East and North Africa Orobanche Management Network (NENAOMAN).     

ISSR标记揭示我国向日葵列当群体的遗传多样性

向日葵列当是目前严重危害我国向日葵生产的寄生性种子植物。为了明确我国不同地区向日葵列当的亲缘关系,本试验利用ISSR标记对采自我国不同省份的96份向日葵列当样本进行了群体遗传多样性的研究。结果表明：从100条ISSR引物中筛选出多态性高、重复性好的12条引物用于群体遗传分析;以供试的列当DNA为模板,利用上述筛选到的引物进行PCR 扩增,共扩增出147 条带,其中90 条具有多态性,多态性条带的百分率为61.2%。不同地区采集的列当群体的Shannon信息指数和Nei′s多样性指数均随着群体样本数量的增加而增大,其中内蒙古地区和新疆地区向日葵列当的多态性相对较高,Shannon信息指数分别为0.5560和0.5067。遗传聚类结果表明6个不同省区的向日葵列当可被聚成两个亚组,其中山西、河北和陕西聚成一个亚组,吉林、新疆和内蒙古聚成另外一个亚组;河北和陕西来源的列当样本亲缘关系最近,而新疆与河北两地的列当样本亲缘关系最远。     

向日葵对盐逆境伤害的生理反应及耐盐性研究

栽植于蛭石的向日葵用0．3％，0．6％，0．9％，1．2％NaCl水溶液胁迫处理，20d,40d时测定生理指标。结果表明：盐逆境对向日葵生长有明显伤害，对叶面积的影响大于对株高的影响；膜透性极显著增加，并随处理时间延长呈上升趋势；脯氨酸含量呈初期上升后期下降趋势；光合速率下降原因与盐浓度有关，低盐度胁迫伤害主要是气孔因素造成的，高盐度胁迫伤害则主要来自非气孔因素。     

大豆底荚高度QTL定位及候选基因挖掘

底荚高度是衡量大豆品种是否适宜机械收获的关键指标。底荚高度较低的品种在机械收割过程中可能造成植株部分被切断或漏割,引起总产量损失。因此,大豆底荚高度候选基因对大豆机械化育种至关重要。本研究利用完备区间作图法(Inclusive Composite Interval Mapping, ICIM)对208染色体片段代换系群体(chromosome segment substitution lines, CSSL)进行大豆底荚高度QTL定位,获得9个与大豆底荚高度相关的QTL,分布在8条连锁群上。结合BSA重测序结果,将与大豆底荚高度相关的QTL定位到C1连锁群上1.1Mb和L连锁群上0.05Mb的区间内,并对其进行基因注释。通过基因注释数据库和信息学分析,在两个共识QTL区间内获得5个可能与大豆底荚高度相关的候选基因。这些结果可以为大豆底荚高度QTL精细定位以及机械化优质高产大豆品种的选育提供理论依据。     

基于BSA-Seq技术鉴定大豆耐荫性状相关候选基因

间套种是我国南方大豆种植的重要模式,而高秆作物的遮荫胁迫导致大豆产量和品质难以提升,是制约大豆间套种发挥潜力的限制因素,因此对大豆耐荫性的解析尤为重要。本研究以强耐荫材料矮脚早和极不耐荫材料齐佩华为亲本构建RILs群体,根据耐荫指数表型鉴定RIL群体的耐荫性,从RIL群体中挑选出强耐荫和极不耐荫家系各30个,分别构建成两个极端性状DNA子代混合池,对子代混合池和亲本池分别开展平均60×和30×覆盖深度的全基因组重测序,通过计算两个子代池的SNP-index,比较SNP-index在耐荫池与不耐荫池染色体各区段的差异,定位耐荫性状的关联区域;根据基因注释信息,预测候选基因。结果表明4个样本共得到11 963 077个单核苷酸多态性（SNPs）标记,发现控制耐荫相关性状的基因主要集中在1号染色体51 942~505 708 bp区段、4号染色体50 972 768~51 854 631 bp区段、9号染色体48 778 767 ~50 178 743 bp区段和18号染色体40 858 027~43 909 456 bp区段内,共包含408个基因,通过基因注释和功能分析发现ACC氧化酶5、生长素诱导蛋白5NG4、光敏色素相关丝氨酸/苏氨酸蛋白磷酸酶、转录因子MYBJ6和MYB128等5个基因可能在大豆耐荫过程中起着重要作用,确定为大豆耐荫性的候选基因。本研究结果将为解析大豆耐荫的分子机理奠定重要的基础,同时为大豆耐荫基因的图位克隆奠定坚实的理论基础。     

向日葵下胚轴体细胞胚发生的基因型效应

为了探讨向日葵不同基因型之间体细胞胚发生能力,采用来源于PAC-2和RHA-266的重组自交系(R ILs)、以及来源于LR35×C149和C149×C40杂交的2个F1杂交种、16个F3家系及其亲本为材料,研究了向日葵下胚轴体细胞胚发生率和每块胚数的基因型效应。结果表明,各基因型之间的胚发生率和每块胚数的差异均达0.1%极显著水平,胚发生率的变幅为0~93.77%,而每块胚数变幅在0~10.63之间;两个群体的杂种F1的胚发生率均显著地高于亲本平均值,表现出一定的优势;重组自交系和杂交F1的两个亲本的胚发生率和每块胚数差异均达显著水平。     

向日葵菌核病田间接种方法及品种抗病性研究

为建立有效的向日葵菌核病田间接种鉴定方法,本研究以菌核病菌菌丝体悬浮液和高粱粒菌丝体作为接种物,分别对不同抗感向日葵品种在始花期和盛花期进行人工接种,从而筛选出最佳接菌物类型、浓度及接种时期,并用此方法对52个品种进行抗性评价。试验结果表明：两种接种物均可使向日葵感病品种产生盘腐症状。用菌丝体悬浮液接种时,7.5~15.0 g/L浓度即可区分出向日葵品种间抗感性差异。始花期接种较盛花期可获得更高的发病率及病情指数。同时筛选出5个对盘腐型菌核病表现抗病的向日葵品种。本研究所建立的田间接种方法能够有效地对向日葵进行抗菌核病筛选和鉴定,可用于向日葵抗菌核病育种。      

Identification of a candidate elongation related gene in rice induced by GA

We identified a gibberellin-induced gene frag- ment in rice elongation by using differentialdisplay(DD)of mRNA.The rice seedlingscarried the eui(elongated)gene,named Zhen- chang A,were used,which were sensitive toGA_3 and elongated rapidly after application ofGA_3. The total RNA were extracted fromseedlings treated for 0,3,8,16,and 24 hwith GA_3(20mg/L),and the RNA of 8 hwere used to conduct mRNA DD assay.A to-tal of 44 DD cDNA fragments were obtained,which were induced or inhibited by GAs from100 combinations of anchor and arbitraryprimers in DD-PCR display(Fig 1).Of the 44DD fragments,GA15b cDNA fragment in- duced by GA_3 was cloned and sequenced.Thisfragment was 673bp in length and was accept-ed by GenBank with the accession number ofAF038894.GA15b gene encodes homology ofextension-like protein,a class of structural by-droxyproline rich glycoprotein of the plant ex-     

利用野生种质构建向日葵细胞质雄性不育源的研究

通过对向日葵野生种菊芋和油葵自交系7718B杂交幼胚的培养，获得了向日葵细胞质雄性不育系CMS514A及其不育保持系CMS514B。通过对其根尖生长点切片的观察,发现其染色体数为2n=34; CMS514A、B 与其它60个试验材料的杂交、自交试验的研究，其保持系与属于CMS PET-1的10个不育系的杂交组合在开花后均有花粉，且自交后代在开花后呈大致3：1的分离比例；CMS514A与属于CMS PET-1的30个保持系和恢复系所做杂交组合在植株开花后均无花粉；CMS514A与包括自交系、常规种、群体品种和其它不育源的保持系、恢复系等育种材料所做的20个杂交组合在开花后也没有花粉。结果表明CMS514为不同于CMS PET-1、CMS-CMG1-CMS-CMG2、CMS-CMG3等不育源的新的向日葵细胞质雄性不育源，其不育性受一对基因控制，遵循植物细胞质雄性不育的遗传规律。     

Genetic variability in the response of fatty acid composition to minimum night temperature during grain filling in sunflower

It is not known if the response of the oil fatty acid composition to temperature is similar among sunflower hybrids, especially among traditional hybrids. The objective of this work was to asses the genetic variability of the response of the oil fatty acid composition to temperature during the period 100–300 °C day after flowering among sunflower hybrids. Seven traditional hybrids and a high oleic hybrid were grown in several locations of Argentina. With the same hybrids two experiments were carried out in growth chambers where the plants were exposed to different day–night temperatures during grain filling. From these field and growth chamber experiments wide ranges of variation of temperature and oil fatty acid compositions for each hybrid were obtained. The concentration of oleic acid in sunflower oil showed a sigmoidal response to minimum night temperature from 100 to 300 °C day after flowering, increasing almost lineally within a given range of temperature. Outside this range, the concentration of this fatty acid remained merely constant. The same mathematical expressions characterized the response of oleic acid concentration to temperature in both, traditional and high oleic hybrids. The same expression also described the response of other fatty acids to temperature in all the hybrids. Differences between hybrids were observed for the minimum and maximum concentration of oleic acid and also for the maximum slope and range of the response. Since the sum of oleic + linoleic acids increased with temperature, increasing temperature reduced the concentration of saturated fatty acids and behenic acid. Genetic variability in the response of these fatty acids to temperature was observed. The results presented here show that it is possible to obtain sunflower oils of very different qualities combining the genetic variability in the response of the fatty acid composition to temperature and the climatic diversity under which sunflower is cultivated.     

大豆胞囊线虫病抗性候选基因GmRSCN-6 克隆与表达分析

大豆胞囊线虫病（Heterodera glycines,Soybean cyst nematode,SCN）是世界性大豆病害之一,具有致病力强、传播范围广、休眠体（胞囊）存活时间长等特点。因此,大豆胞囊线虫病极难防治。筛选并利用抗病基因是加快大豆抗线育种进程的有效途径之一。本文以东农L-10为材料,克隆GmRSCN-6 基因并分析GmRSCN-6蛋白的性质,同时对该基因在抗感病品种进行表达分析。结果表明GmRSCN-6 在SCN3号生理小种侵染10 d内逐渐上调表达。3 d时表达量出现小高峰,推测GmRSCN-6 基因响应SCN3号生理小种入侵信号,10 d时GmRSCN-6 基因的表达量达到最大,且抗病品种中的表达量远高于感病品种,表明GmRSCN-6 基因参与大豆胞囊线虫病3号生理小种抗性反应。     

Non-destructive prediction of chemical composition in sunflower seeds by near infrared spectroscopy

Near infrared reflectance spectroscopy (NIRS) was explored as a technique to predict moisture (M), oil and crude protein (CP) content on intact sunflower seeds (Helianthus annuus L.). Three hundred samples were scanned intact in a monochromator instrument NIRS 6500 (NIRSystems, Silver Spring, MD, USA). Calibration equations were developed using modified partial least square regression (MPLS) with internal cross validation. Samples were split in two sets, one set used as calibration (n=250) where the remaining samples (n=50) were used as validation set. Two mathematical treatments (first and second derivative), none (log 1/R) and standard normal variate and detrend (SNVD) as scatter corrections were explored. The coefficient of determination in calibration (R_cal²) and the standard error in cross validation (SECV) were 0.95 (SECV: 3.3) for M; 0.96 (SECV: 13.1) for CP and 0.90 (SECV: 22.3) for oil in g kg⁻¹ on a dry weight basis (second derivative, 400–2500 nm). Prediction models accounted for less than 65, 70 and 72% of the total variation for oil, M and CP, respectively. However, it was concluded that NIRS is a suitable technique to be used as a tool for rapid pre-screening of quality characteristics on breeding programs.     

Field evaluation of the resistance of some faba bean (Vicia faba L.) genotypes to the parasitic weed Orobanche foetida Poiret

Heavy infestation of faba bean fields by Orobanche foetida is an emerging problem in Tunisia. Field trials during three consecutive crop seasons demonstrated the resistance of three genotypes to O. foetida, including the cv. Baraca, selected for resistance to O. crenata, and two Tunisian breeding lines, Bader and XBJ90.03-16-1-1-1. Resistant genotypes displayed a parasitism index two-fold lower than that of the susceptible checks. They carried 2–8 times less of tubercle attachments and 2–3 times less of emerged parasite spikes at pod setting stage and at crop maturity, respectively. Seed-yield losses by parasitism reached 90% for the susceptible checks and were two-fold lower for the resistant genotypes. Parasitism affected negatively the protein/starch ratio of seeds of both susceptible and resistant genotypes. The line XBJ90.03-16-1-1-1 was the best candidate for registration because of better productivity in non-infested fields and production of high-weight seeds.     

Antioxidant potential of sesame (Sesamum indicum) cake extract in stabilization of sunflower and soybean oils

Recently natural antioxidants have gained increased interest because natural food ingredients are safer than synthetic ones. Antioxidant activities and protective effects of sesame cake extract (SCE) in stabilizing sunflower oil (SFO) and soybean oil (SBO) were tested. Since different antioxidant compounds have different mechanisms of action, 2,2-azinobis (3-ethylbenzthiazoline sulfonate) (ABTS) radical scavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, and β-carotene/linoleic acid test system were used to assess the antioxidant efficacy of SCE. Total phenolic, flavonoid and flavonol contents in SCE were 1.94 (mg gallic acid equivalent (GAE) g⁻¹ dry weight (DW)), 0.88 (mg quercetain equivalent (QE) g⁻¹ DW), and 0.40 (mg QE g⁻¹ DW), respectively. Protective effects of SCE in stabilizing SFO and SBO were tested, compared to synthetic antioxidants, by measuring their peroxide values (PV), conjugated dienes (CD), conjugated trienes (CT) and p-anisidine value during accelerated storage. Results indicated that SCE exhibited stronger antioxidant activity in SFO and SBO than butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), while its antioxidant activity was less than that of tert-butyl hydroquinone (TBHQ).