不同列当抗性的向日葵品种根系分泌物对向日葵列当种子萌发的影响

以对向日葵列当抗性不同的向日葵幼苗为材料,利用水培法收集其根系分泌物,经二氯甲烷萃取后结合硅胶柱色谱分离法,研究不同列当抗性的向日葵品种根系分泌物对向日葵列当种子萌发的影响。结果表明:(1)在一定浓度范围内,向日葵根系分泌物对向日葵列当种子萌发具有低浓度促进、高浓度抑制的作用;二氯甲烷萃取的向日葵根系分泌物浓度为0.1mg/mL时,其向日葵列当萌发率高于其他浓度的作用。(2)‘星火大白边’和‘白葵杂9号’根系分泌物提取物作用下向日葵列当萌发率最高分别为46.92%和43.88%,显著高于免疫品种‘MGS’根系分泌物提取物作用下列当的萌发率(27.81%)。(3)根系分泌物提取物正己烷-乙酸乙酯1∶1洗脱组分的萌发刺激活性显著高于其他组分,‘星火大白边’、‘白葵杂9号’和‘MGS’的该组分作用下向日葵列当最高萌发率分别为49.90%、45.66%和30.00%。(4)‘MGS’的根系分泌物提取物与GR24或脱氢木香内酯共同作用时种子萌发率显著低于GR24或脱氢木香内酯的单独作用,说明‘MGS’根系分泌物中可能含有抑制GR24或脱氢木香内酯刺激向日葵列当种子萌发的物质,使其对向日葵列当表现出免疫特性。     

土壤条件对向日葵列当寄生的影响

以高感列当的向日葵品种‘龙食葵2号’为试验材料,采用室内接种列当温室培养的方法,研究土壤条件对向日葵列当寄生与生长的影响。结果表明：（1）土壤质地对向日葵列当的寄生具有显著影响,培养50 d时,沙壤土、壤土、粘土中列当的出土数分别为 32.2、19.5和4.6个,平均单株寄生列当数量分别为38.8、24.0和8.2个,说明通透性好的沙壤土有利于列当瘤的形成与生长。（2）在沙壤土条件下,随着处理温度的上升,列当的出土数量和寄生数量均呈先升高后降低的趋势;当培养温度为25 ℃和30 ℃时,向日葵列当有较高的寄生数量与生长速度,列当出土数和平均单株寄生列当数量分别为30.4、31.6和39.8、39.4个。（3）在沙壤土条件下,随着土壤湿度的增加,列当的出土数量和寄生数量呈先升高后降低的变化趋势,并在土壤湿度为60%和70%达到较高值,列当出土数和平均单株寄生列当数量分别为32.6、30.9和39.9、40.9个,而在高湿条件下列当的寄生数量显著减少。（4）在沙壤土条件下,随着土壤pH值的增加,列当的出土数量和寄生数量也呈先升高后降低的变化趋势,并均在土壤pH值为8时达到最大值,列当出土数和平均单株寄生列当数量分别为47.5和51.1个,即列当在偏碱性的土壤环境中有着较高的寄生数量。研究发现,当土壤类型为沙壤土、土壤温度为25~30 ℃、土壤湿度为60%~70%、土壤 pH为8时有利于向日葵列当的寄生与生长;在实际生产中应选择中性或偏酸性的非沙壤土地种植向日葵,并注意调整播期和控制田间灌水量,以降低向日葵列当的危害。     

向日葵对列当寄生的生理响应及关键代谢通路分析

【目的】分析向日葵对列当寄生的生理响应及其相关代谢通路,揭示向日葵对列当寄生的抗性分子机制。【方法】以抗列当向日葵材料(s41)和感列当向日葵材料(s26)为供试材料进行接种列当处理,对正常生长(s41_CK,s26_CK)和列当寄生胁迫(s41,s26)条件下的4个样本进行转录组测序分析,同时对部分关键代谢物质进行生理验证分析。【结果】(1)在列当接种条件下,向日葵高感列当材料的植株高度和根量明显受到抑制,而且已有部分列当出土,而高抗列当材料无明显变化,仅有极少数列当寄生。(2)通过对样品间进行差异基因筛选,得到差异表达基因(DEGs)数量分别为6 362,6 609,5 490,5 469个。GO分析表明,s26-s41、s26_CK-s41_CK、s26-s26_CK、s41-s41_CK 4个比较组参与生物过程的差异基因数量较多,参与细胞组分的差异基因数量次之,参与分子功能的较少;KEGG分析表明列当寄生对向日葵的植物信号转导、次生代谢物的生物合成、脂质代谢、...     

列当寄生对不同品种向日葵幼苗生长及抗氧化酶活性的影响

采用连作重茬含向日葵列当的土壤,进行不同列当抗性向日葵品种苗期盆栽试验,调查播种后第30、50和70天向日葵幼苗根系列当的寄生率、幼苗地上部和地下部干物质量及株高,并测定其叶片丙二醛(MDA)、苯丙氨酸解氨酶(PAL)、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性。结果表明:不同向日葵品种苗期对列当抗性明显不同,其中油葵品种‘T012244’和‘MGS’对向日葵列当寄生免疫,‘S31’和‘白杂9号’为高抗,而‘星火大白边’和‘白杂6号’为敏感。列当寄生后明显抑制敏感品种向日葵幼苗生长,而对免疫品种和高抗品种的影响较小。列当寄生后的敏感性品种‘星火大白边’幼苗叶片MDA含量迅速上升,PAL活性也大幅度增加,列当对幼苗生长伤害加重;而苗期免疫品种"T012244"和高抗品种"S31"MDA含量下降,PAL活性则变化不大。随接种时间延长,不同抗性向日葵品种苗期SOD、POD和CAT活性均呈现先升高后降低的变化趋势,且免疫品种的保护酶活性变化幅度大于敏感品种,说明列当寄生对敏感向日葵品种造成了逆境胁迫,诱导其幼苗叶片保护酶系统产生防御响应。     

Streptomyces rochei D74菌剂对向日葵、列当及其根际微生物的影响北大核心

【目的】研究娄彻氏链霉菌(Streptomyces rochei)D74菌剂促进向日葵生长和抑制列当寄生的作用,及其对根际微生物的影响。【方法】通过构建向日葵-列当-S.rochei D74共培养体系,观察D74菌株对列当寄生的影响;采用田间小区试验,测定D74菌剂接种对向日葵植物生理指标和列当出土数的影响;测定向日葵产量指标,研究D74菌剂对向日葵籽粒品质及产量的影响;利用16S rRNA基因高通量测序技术和传统微生物培养方法,分析添加D74菌剂对向日葵根际微生物群落结构的影响。【结果】D74菌剂能够促进向日葵生长[茎秆重和花盘重分别显著增加(P<0.05)37%-40%和21%-37%],同时抑制28%-46%(P<0.05)的列当出土;还可以提高向日葵籽粒中粗蛋白含量5%-9%、大粒占比约66%(P<0.05)和百粒重8%-18%,并且通过产量测定表明,D74菌剂可增产约30%(P<0.05),这对提高农民经济收益具有深远意义。D74菌剂对向日葵根际微生物群落具有显著影响,调节了群落有益微生物数量。【结论】D74菌剂可以显著降低向日葵根部列当寄生病害的发生,促进花盘生长,使籽粒饱满,具有实际应用价值和推广意义。     

新疆列当的种类、分布及其防治技术研究进展

列当是一种根寄生种子植物,是我国进境植物检疫对象,同时也是我国的内检对象。新疆是我国列当发生面积最大、危害最重和种类最多的地区,对新疆的主要经济作物,如加工番茄、向日葵、甜瓜等已造成严重危害。在新疆文献记载的列当种类有18种,常见的有埃及列当、大麻列当、向日葵列当和弯管列当,并已广泛分布于新疆各县、市、团场。列当的防治技术主要包括检疫、田间管理、轮作等,但目前的防治效果均不理想。本文通过对新疆列当的相关文献搜集、整理分析,总结了目前新疆列当的种类、分布情况,以及综合防治技术,为今后列当的研究和防治提供参考。     

中国食用向日葵育种国产化历程及研究进展

中国食用向日葵育种近40年来取得了巨大成就,实现了从自留农家种、选育常规品种、引进国外杂交种以及培育国产杂交种4 次品种更新。中国向日葵种植面积基本保持在59万hm²左右,种植区主要集中在北方10个省区,其中内蒙古自治区种植面积约占全国总面积的四分之三,其次是新疆。中国以食用向日葵种植为主,约占总面积的95%以上,是世界上食用向日葵主要生产国。食用向日葵主要用于休闲嗑食,除高产外,商品外观品质(粒型、色泽、口感等)仍将是当今主要育种目标。另外,向日葵生产区因长期连作种植,病原菌、列当等生物逆境因素与向日葵发生协同进化,加之食用向日葵遗传背景狭窄,病虫草害日趋严重。该文通过对中国食用向日葵育种历程进行回顾,尤其对国内外有关向日葵抗病育种研究进展进行综述,为解析食用向日葵抗性育种机制以及前瞻性抗性品种储备提供重要的理论与技术支持,以推动食用向日葵产业的高效优质发展。     

‘锦苗标靶’诱抗剂抑制列当寄生向日葵的机制研究

该研究通过对2个向日葵品种(LD5009 和JK103)根系浇灌‘锦苗标靶’诱抗剂,于浇灌处理后0、24、48 和72 h分别对根系取样进行组织化学分析,测定根系H₂O₂含量、ROS清除酶活性以及抗性相关基因表达,并于浇灌处理后20 d检测向日葵生长指标和根瘤结数量,以明确‘锦苗标靶’对向日葵抑制列当寄生的诱抗机制。结果显示：(1)与对照(施用清水)相比,LD5009在‘锦苗标靶’处理后,列当瘤结数减少了95.5个,寄生率降低了98.20%;瘤结的鲜质量和干质量分别降低了94.60%和81.63%,而向日葵株高和茎粗分别相应增加了2.09 cm和0.52 mm,增长率分别为14.92%和15.29%;JK103在‘锦苗标靶’处理后,列当瘤结数较对照减少了37.5个,寄生率降低了98.04%,瘤结的鲜质量和干质量也分别降低了97.06%和82.69%,而向日葵的株高和茎粗分别增加了2.07 cm和0.39 mm,增长率分别为12.26%和9.70%。(2)‘锦苗标靶’诱抗剂浇灌处理后,2个向日葵品种根系中胼胝质的沉积量均有增加,但以JK103在处理48 h后增加幅度最为明显;JK103和LD5009中H₂O₂含量在处理24 h后均达到最大值,分别为3.53和2.68 μmol·g^-1,与对照相比,LD5009的H₂O₂含量增幅较大,为208.05%。(3)2个品种的ROS清除酶活性在处理后均呈先升高后降低的趋势,且均在处理48 h后达到最大值;JK103+锦苗标靶处理较清水对照的SOD、POD、CAT、PPO活性分别增加了69.77 U·g^-1、5.44 U·g^-1·min^-1、1.88 U·g^-1·min^-1和527 U·g^-1·min^-1,而LD5009+锦苗标靶处理后,上述4种酶的活性分别增加了25.91 U·g^-1、13.16 U·g^-1·min^-1、0.50 U·g^-1·min^-1和313 U·g^-1·min^-1。(4)抗性相关基因转录水平的检测结果显示,施用诱抗剂后2个品种抗性基因的转录水平都不同程度地被诱导,但以LD5009+锦苗标靶样本中被诱导的幅度最为明显,特别是CAT、Mn SOD和XTH6基因,其转录水平比对照均上调了50倍之多。研究表明,诱抗剂‘锦苗标靶’对向日葵列当的寄生有显著的抑制效果,且在向日葵列当寄生前(瘤结未形成)施用效果更佳;‘锦苗标靶’可促进向日葵根系细胞中胼胝质的沉积量增加,在结构水平上抵御列当对向日葵根系的侵染,并能够诱导向日葵根系ROS清除酶活性以及CAT、PAL、Mn SOD和XTH6等基因表达的提高,从而建立向日葵对列当寄生的获得性抗性,但诱导的程度由于品种不同而存在一定的差异。     

列当王国探奇

被子植物中的列当科,全是寄生草本植物,有15属150多种,中国有9属40多种。该科植物形态奇特,生活习性引人入胜,一些药用种类久已闻名。 列当小王国 列当(Orobanche coerulescens)是列当科的习见种之一,在我国北方分布较广,但以往见到的多是零星生长的少量植株。一年夏天,在山西五台山下的一片撂荒地田,笔者意外地见     

逆境胁迫下向日葵的耐受机制

向日葵作为我国五大油料作物之一,具有极高的食用价值和油用价值。向日葵在我国的种植分布集中在东北、西北和华北地区,时常面临着干旱、盐碱、温度和重金属胁迫的问题。主要综述了近年来向日葵面临的几种主要逆境胁迫的最新研究进展,以及在不同逆境胁迫下向日葵的耐受机制,并根据不同逆境胁迫筛选出了相应的抗逆向日葵品种,同时进行了生理差异和基因信息分析。通过阐明向日葵在逆境胁迫下的耐受机制,以期对向日葵高产育种及耐逆育种提供理论依据和指导方向。     

Some Soybean Cultivars Have Ability to Induce Germination of Sunflower Broomrape

Sunflower broomrape is a noxious parasitic weed which has caused severe damage to crop ecosystems. Trap crops can release a mixture of allelochemicals to induce the germination of sunflower broomrape. We studied the allelopathic effects of soybean on sunflower broomrape. Fourteen common soybean cultivars were grown in pots. Samples were collected from soybean plants and rhizosphere soil at five growth stages (V1, V3, V5, R2, and R4). The allelopathic effects of soybean reached highest at the V3 stage. Methanolic extracts of soybean roots induced higher broomrape germination than methanolic extracts of stems or leaves. The germination rates induced by root extracts (10-fold dilution) were positively correlated with germination rates induced by stem (10-fold dilution) and leaf extracts (10-fold dilution). The broomrape germination rates induced by root extracts were also positively correlated with soybean nodule diameter and dry weight. The results indicated that soybeans could induce sunflower broomrape germination. We conclude that soybean has the potential to be used as a trap crop for sunflower broomrape.     

向日葵组织培养研究进展

向日葵(Helianthus annuus)是世界主要的油料作物之一.近几年来有关向日葵的研究很多,其中向日葵组织培养研究越来越受到重视.本文从向日葵外植体培养、植株再生影响因素、组培过程中存在的问题及解决方法等方面进行了综述.     

Sesame genotype influences growth and phenology of Phelipanche aegyptiaca

Egyptian broomrape (Phelipanche aegyptiaca) is a parasitic weed causing major yield loss in many field and vegetable crops. Recent observations in Iran suggest that sesame (Sesamum indicum) may serve either as a trap crop or as a host for broomrape, depending on genotype. The central objective of this research was to identify sesame genotypes that could act either as potential trap crops, or sources of genetic material for development of broomrape resistant cultivars. Seeds of 11 Iranian sesame genotypes (Ardestan, Esfarayen, Oltan, Ahvaz, Borazjan, Darab‐14, Ferdous, Kalat, Naz Tak Shakhe, Varamin and Yekta) and 10 foreign genotypes (S16, S21, S23, S25, S4, S5, S6, S7, S8 and S9) were planted with broomrape seeds in pots. At the flowering stage of sesame, tubercle number and dry weight, shoot number and dry weight and shoot height of broomrape were determined. Shoot dry weight, root dry weight and seed yield of sesame were determined at the physiological maturity. The results showed that broomrape growth varied with sesame genotype. Egyptian broomrape dry weight measured from 1.6% (S23) to 35.4% (Kalat) of the dry weight of the sesame on which it grew. Broomrape total dry weight had positive and highly correlation with the root dry weight of the sesame genotype on which it grew. When broomrape planted with the S7, S8, S9, S21 and S23 genotypes produced tubercles, but no shoots on these genotypes. Such genotypes could be used as both trap crops and as breeding‐sources for development of resistant sesame genotypes.     

Die Bedeutung elektrophoretischer Proteinanalysen bei phytopathogenen Pilzen als Hilfsmittel zu ihrer taxonomischen Charakterisierung

Sunflower is one of the most important oilseed crops, which is grown in many countries. Increasing demand to use sunflower oil has expanded the under cultivation area throughout the world. Sunflower viruses have been reported as one of the pathogens that reduce the quantity and the quality of this product in a number of countries. In our research to study the occurrence and distribution of viruses in sunflower fields of Iran, 562 samples were collected from different fields in Kerman and Isfahan provinces during growing seasons from 2009 to 2011. Potato virus Y (PVY), Cucumber mosaic virus (CMV) and Tomato spotted wilt virus (TSWV) were detected by double antibody sandwich enzyme-linked immunosorbent assay. Also, numbers of samples were positive for infection to potyviruses (except PVY) in antigen-coated-plate enzyme-linked immunosorbent assay test using potyviruses general antiserum. Infected plants had symptoms like mosaic, yellowing, deformation, necrotic and chlorotic lesions and mottling on leaves and stunting. The infection rates of potyviruses, PVY, CMV and TSWV in Isfahan province were 33, 22, 4.18 and 3.25% of collected samples, respectively. The corresponding rates for samples from Kerman province were 15, 5, 0.8 and 0.4% of collected samples. According to these results, viral infection in Isfahan province was more than surveyed in Kerman province during the mentioned period of three years. Furthermore, generally there was a decrease in the percentage of viral infection during this three growing seasons in both provinces. This is the first report of the detection of CMV and TSWV in sunflower fields of Isfahan and Kerman and first report of PVY in Isfahan.     

Conditioning duration and agents involved in broomrape seeds responding to germination stimulants

Weedy broomrape species, such as sunflower broomrape (Orobanche cumana Wallr.) and Egyptian broomrape [Phelipanche aegyptiaca Pers. (syn. O. aegyptiaca)], require a period of pre-conditioning before they can respond to germination stimulants. Thus, the sensitivity of weedy broomrape seeds to germination stimulants could be an important factor for broomrape control. In this study, the influence of conditioning agents, conditioning period (0–21 days) and germination stimulants on the germination of sunflower broomrape and Egyptian broomrape seeds was analyzed. Without conditioning, the sunflower and Egyptian broomrape seeds exhibited negligible germination responses to the stimulants. The germination rate of the broomrape seeds increased rapidly with conditioning period and reached a maximum under a conditioning period of 4–10 days; further prolonged conditioning resulted in a decrease in the germination rate. Gibberellic acid (GA₃) could not only break the dormancy of the sunflower and Egyptian broomrape seeds but also maintained the high sensitivity of these seeds even after 21 days of conditioning. Furthermore, 100 µM of GA₃ induced the germination of the Egyptian broomrape seeds. The stimulants that induced Egyptian broomrape germination were ranked in decreasing order as GR24 (76.8?%), strigol (76.1?%), tobacco root exudates (49.5?%), dehydrocostus lactones (DCL, 39.2?%), and maize root exudates (18?%). In contrast, GA₃ did not directly induce sunflower broomrape seed germination, which responded to strigol (62.8?%)?>?maize root exudates (58.2?%)?>?GR24 (57.9?%)?>?tobacco root exudates (41.6?%)?>?DCL (41.3?%). These results indicate specialized recognition of germination stimulants by sunflower and Egyptian broomrape. This study may contribute to a better understanding of parasitic weed germination and may lead to improved control strategies.     

Improved salinity tolerance and growth performance in transgenic sunflower plants via ectopic expression of a wheat antiporter gene (TaNHX2)

Molecular Biology Reports - Sunflower (Helianthus annuus. L) is one of the principal oil seed crops affected by the salinity stress, which limits the oil content and crop yield of sunflower plants....     

Isolation of HMW DNA from sunflower (Helianthus annuus L.) for BAC cloning

The cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops in the world. The importance of sunflower oil in human nutrition and in the chemical industry makes the sunflower a major research interest. An essential element for genomic libraries is the preparation of high molecular weight (HMW) DNA. We developed 2 methods for isolating HMW sunflower DNA. We prepared the DNA from nuclei and from protoplasts isolated from mesophyll tissue with the enzymes cellulase RS and pectolyase Y23. The HMW DNA was digested with restriction endonucleases. The ethidium bromide-stained gel suggested the DNA to be completely digested. These results were confirmed by Southern analysis using a radiolabeled RFLP marker. Both methods made it possible to generate sufficient quantities of megabase-size sunflower DNA suitable for bacterial artificial chromosome (BAC) cloning.     

Sunflower as a trap crop for the European tarnished plant bug (Lygus rugulipennis)

The European tarnished plant bug, Lygus rugulipennis (Heteroptera: Miridae), inflicts serious damage to glasshouse crops, including cucumber, in which it causes distorted foliage, dead growing points and malformed fruits. In a research involving commercial growers, we tested the possibility of using a trap crop to control L. rugulipennis. We screened the attraction of sunflower and lucerne as trap crops using an olfactometer. Adults (females and males) were more attracted to the odour of either flowering sunflower or lucerne than flowering cucumber. In a glasshouse trial, potted flowering sunflowers were evaluated as a trap crop placed at the ends of each cucumber row. Although the trap crop showed much higher attractiveness than the cucumber crop, this effect was not sufficient to provide an acceptable level of control according to the commercial growers. The growers suggested developing artificial sunflower odour as a more efficient lure for removal trapping. As a first step in this development, we tested the attraction of the headspace odour collected from sunflower in olfactometer trials. Sunflower headspace attracted a higher number of adults compared to a blank or a flowering cucumber. The sunflower odour was analysed by gas chromatography coupled to mass‐spectrometry to determine compounds possibly involved in L. rugulipennis attraction. The chemical analysis of the plant odour showed a well‐defined differentiation between sunflower and cucumber, with a number of monoterpenes released exclusively by sunflower. This, plus an emission rate from sunflower being at least four times more abundant, opens the possibility of using synthetic sunflower volatiles to attract L. rugulipennis within a cucumber background.