用SSR标记研究柑橘属及其近缘属植物的亲缘关系

用SSR标记分析了29份柑橘属及近缘属植物的亲缘关系。7对SSR引物在29个样品中扩增得到114个等位基因,平均每个位点有16.3个等位基因。计算匹配系数后用邻接法进行聚类,结果表明,澳洲指橘与柑橘属的亲缘关系很近;SSR位点的高纯合频率支持富民枳种的地位;枳与柑橘属的关系较远,枳不大可能是从柑橘属衍生而来;Swingle的亚属的划分以及田中的原生柑橘类和后生柑橘类的划分界线不清晰;现代栽培柑橘的起源与大翼橙关系密切;柑橘属的枸橼、柚和宽皮橘都很好地分离,支持其为现代栽培柑橘的3个基本种的观点。     

柑橘类柠檬苦素抗癌活性研究进展

柑橘作为受人喜爱的第一大果品,其主要次生代谢产物类柠檬苦素具有抗癌、降低胆固醇、镇静、催眠、抗焦虑、抑菌、抗病毒等多种生物活性。近年来,柑橘类柠檬苦素抗癌活性已成为国际研究热点并广受社会关注。该文从清除自由基、激发谷胱甘肽转移酶、降低致癌物质致癌活性以及抑制肿瘤细胞增殖等四个方面综述了柑橘类柠檬苦素抗癌国际最新研究进展,并对柑橘类柠檬苦素抗癌活性及其构效关系进行了讨论。     

柑橘大实蝇生物、生态学及辐照不育技术最新研究进展

柑橘大实蝇是柑橘类果树的一种重要害虫,近几年在我国柑橘种植区的危害呈上升趋势,给柑橘产业造成了巨大损失。本文概述了环境因素包括温度、光周期、营养状况(饥渴)以及水淹对柑橘大实蝇生物学特性和成虫行为的影响,柑橘大实蝇成虫和幼虫人工饲养技术参数,柑橘大实蝇蛹滞育机制,辐照不育关键技术包括最佳辐照剂量和辐照时期,及其在湖北柑橘园柑橘大实蝇防控中的应用与示范情况等,并指出了尚需进一步开展的研究内容。     

柑橘溃疡病及其微生物防治研究进展

柑橘是我国第一大水果,柑橘溃疡病是导致柑橘产量和品质下降的最具破坏性细菌性病害之一,给柑橘产业造成了巨大的经济损失,严重阻碍了柑橘产业的可持续发展。微生物防治柑橘溃疡病具有安全、环保、高效等优点,是当前研究的热点。本文主要概述了柑橘溃疡病特征及其病原菌分类、分布,全面分析了柑橘溃疡病病原菌主要致病机理和协助致病机理;系统梳理了柑橘溃疡病生防微生物的多样性;重点总结了微生物通过产生活性物质、诱导激活植物免疫防御系统等防治柑橘溃疡病的作用机制;最后,我们提出了柑橘溃疡病微生物防治面临的挑战以及未来可能的解决途径,以期为柑橘产业的健康发展提供参考。     

柑橘类果实枯水机理及防治研究进展

对柑橘类果实枯水过程中果皮、果肉的解剖结构和一些生理生化指标的变化,以及导致枯水发生的因素及控制措施的研究进展进行了综述,分析了柑橘枯水的可能机理。     

柑橘木虱蜜露排泄机制:进展与展望

半翅目昆虫柑橘木虱Diaphorina citri是柑橘类果树重要害虫,主要以高渗透压的植物韧皮部汁液为食,是柑橘毁灭性病害——柑橘黄龙病(HLB)的主要传播媒介。柑橘木虱取食韧皮部汁液时自身进化出一套完整的渗透调节机制调节其体内渗透压,将体内过量摄入的糖类转化成长链寡糖并以蜜露形式排出体外。本文从柑橘木虱蜜露排泄行为、蜜露组成成分以及影响蜜露排泄的多个因素进行了论述,同时综述了可能参与柑橘木虱蜜露排泄行为的渗透调节基因。研究表明,柑橘木虱雌雄成虫及若虫在蜜露排泄行为上存在显著差异,且排泄的蜜露在颜色、纹路及组成成分方面均有不同;寄主植物、杀虫剂、病原微生物及天敌化合物均会影响柑橘木虱蜜露排泄行为。分子机制探究发现,α-葡萄糖苷水解酶、水通道蛋白及糖基转移酶基因等关键渗透调节基因可能参与调控柑橘木虱蜜露排泄行为。本文可为未来有关柑橘木虱蜜露排泄行为方面的研究以及为研制柑橘木虱防治新型药剂开发新靶标提供参考。     

封面照片

正照片示柑橘大实蝇Bactrocera minax雄成虫(双翅目:实蝇科)在板栗园中的中国板栗Castanea mollissima(壳斗目:壳斗科)雄花花序上访花。柑橘大实蝇是主要分布于我国的柑橘类重要害虫,也是对外检疫对象之一。其成虫必须经过营养补充期,生殖腺才能逐渐发育成熟。本期报道了柑橘大实蝇成虫在中国板栗雄花花序上的取食行为(pp.458-467)。照片由何章章于2017年6月摄于湖     

中国主要农作物产量波动影响因素分析

为研究我国主要农作物(粮食、水果、油料、糖料和棉花作物)产量波动特征及相关影响因素,以我国1981 ～2010年主要农作物产量和种植面积资料为基础,同时利用4种方法对农作物单产进行趋势拟合与分解.结果表明:(1)近30年来我国农作物总产和单产都逐步提高,特别是水果产量的增长最快,其中柑橘单产年均增长率达7.09％;各类作物趋势产量也呈上升趋势;但气象产量波动剧烈,年际间缺乏连续性,其中水果气象产量波动幅度最大(柑橘为17.76％、苹果为15.83％).(2)作物总产的年际波动中,种植面积和单产因素的贡献率因作物类型不同而有所差异,其中粮食作物和水果总产波动的主要原因是单产波动,糖料作物和棉花产量波动主要因种植面积波动导致,油料作物总产的波动中单产和种植面积贡献相当.(3)各类作物单产年际波动均取决于气象因素,农业政策和科技进步等社会因素对单产年际波动的贡献较低.(4)作物趋势产量的4种拟合方法,其结果无显著差异.各影响因素对我国农作物产量波动的贡献率因作物类型不同而有所差异;重视作物单产提高、关注气候变化对农作物生产的影响是目前我国农业安全生产的重要任务.     

柑橘大实蝇成虫对板栗挥发物的行为反应

柑橘大实蝇Bactrocera minax(Enderlein)是为害柑橘类果实的毁灭性害虫。本研究采用顶空捕集法和气相色谱-质谱联用技术,对中国板栗挥发物进行了初步鉴定,并利用Y型嗅觉仪测定了1日龄和3日龄柑橘大实蝇雌、雄成虫对3种不同处理中国板栗和7种挥发性化合物的选择行为反应。结果表明中国板栗对柑橘大实蝇成虫具有极显著的诱引作用。中国板栗挥发物中含有26种化学成分,主要为一些芳香烃类、酸类、醛类、酮类、醇类、萜烯类、酯类和胺类化合物。柠檬烯、异丁醛、α-蒎烯、苯乙酸甲酯对柑橘大实蝇成虫表现出显著的诱引作用,乙偶姻和戊醛对柑橘大实蝇成虫表现出显著的驱避作用。结果进一步表明柑橘大实蝇成虫的嗅觉行为反应与化合物的浓度和成虫的日龄及性别有关,这为柑橘大实蝇成虫植物源引诱剂的开发和应用提供了一定的理论依据。     

柑橘属植物中抗肿瘤活性成分的研究进展

芸香科柑橘属植物作为传统中药材一直受到普遍关注,尤其近年来对其在抗肿瘤方面的研究已成为国内外研究的热点.综述了近年来国内外学者对柑橘类植物所含抗肿瘤活性成分的最新的研究进展,并分别对它们抗肿瘤的作用机制进行了初步的探讨.     

The citrus fruit proteome: insights into citrus fruit metabolism

Fruit development and ripening are key processes in the production of the phytonutrients that are essential for a balanced diet and for disease prevention. The pathways involved in these processes are unique to plants and vary between species. Climacteric fruit ripening, especially in tomato, has been extensively studied; yet, ripening of non-climacteric fruit is poorly understood. Although the different species share common pathways; developmental programs, physiological, anatomical, biochemical composition and structural differences must contribute to the operation of unique pathways, genes and proteins. Citrus has a non-climacteric fruit ripening behavior and has a unique anatomical fruit structure. For the last few years a citrus genome-wide ESTs project has been initiated and consists of 222,911 clones corresponding to 19,854 contigs and 37,138 singletons. Taking advantage of the citrus database we analyzed the citrus proteome. Using LC-MS/MS we analyzed soluble and enriched membrane fractions of mature citrus fruit to identify the proteome of fruit juice cells. We have identified ca. 1,400 proteins from these fractions by searching NCBI-nr (green plants) and citrus ESTs databases, classified these proteins according to their putative function and assigned function according to known biosynthetic pathways.     

柑橘重要害虫寄生性天敌的研究与利用进展

柑橘是我国重要的岭南特色水果,种植面积广,产量大。在生产过程中,柑橘容易受到各类病虫害的危害。因为害虫抗药性的产生以及化学农药使用带来的负面影响,害虫生物防治成为今后柑橘害虫可持续防控的重要策略。本文以桔小实蝇、柑橘木虱、介壳虫以及柑橘潜叶蛾、柑橘卷叶蛾、柑橘凤蝶等柑橘重要害虫及其寄生蜂为研究对象,对近年来国内外在柑橘害虫生物防治领域,尤其是寄生蜂的研究与利用等方面取得的最新进展进行了综述,以期不断推进我国柑橘害虫生物防治技术的研究与应用,保障我国柑橘产业的健康发展。     

The aconitate hydratase family from <Emphasis Type="Italic">Citrus</Emphasis>

Background  

Research on citrus fruit ripening has received considerable attention because of the importance of citrus fruits for the human diet. Organic acids are among the main determinants of taste and organoleptic quality of fruits and hence the control of fruit acidity loss has a strong economical relevance. In citrus, organic acids accumulate in the juice sac cells of developing fruits and are catabolized thereafter during ripening. Aconitase, that transforms citrate to isocitrate, is the first step of citric acid catabolism and a major component of the citrate utilization machinery. In this work, the citrus aconitase gene family was first characterized and a phylogenetic analysis was then carried out in order to understand the evolutionary history of this family in plants. Gene expression analyses of the citrus aconitase family were subsequently performed in several acidic and acidless genotypes to elucidate their involvement in acid homeostasis.     

影响柑桔树开花结果性能的生态生理因素

本文报道1988年和1989年春夏之际异常和正常的桔园小气候环境对柑桔树开花结果物候期、抽梢生长、幼果发育、生理落果、当年果实产量和品质等性能的影响。结果表明,柑桔树的座果率受许多生态生理因素制约,但第一次生理落果主要与开花期桔园的小气候环境有关,第二次生理落果则与树体营养生理代谢密切相关。据此提出了预测预报柑桔树第二次生理落果的指标及其防御措施。     

Genome-wide identification and expression analysis of MATE gene family in citrus fruit (Citrus clementina)

Multidrug and toxic compound extrusion (MATE) proteins are a class of secondary active multidrug transporters. In plants, this family has significantly expanded and is involved in numerous plant physiological processes. Although MATE proteins have been identified in an increasing number of species, the understanding about this family in citrus remains unclear. In this study, a total of 69 MATE transporters were identified in the citrus genome (Citrus clementina) and classified into four groups by phylogenetic analysis. Tandem and segmental duplication events were the main causes of the citrus MATE family expansion. RNA-seq and qRT-PCR analyses were performed during citrus fruit development. The results indicated that CitMATE genes showed specific expression profiles in citrus peels and flesh at different developmental stages. Combined with the variations of flavonoids and citrate levels in citrus fruit, we suggested that CitMATE43 and CitMATE66 may be involved in the transport process of flavonoids and citrate in citrus fruit, respectively. In addition, two flavonoids positive regulators, CitERF32 and CitERF33, both directly bind to and activated the CitMATE43 promoter. Our results provide comprehensive information on citrus MATE genes and valuable understanding for the flavonoids and citrate metabolism in citrus fruit.     

柑橘采后品质变化及保鲜技术研究进展

柑橘Citrus spp.是中国南方重要的热带、亚热带果树,其果实具有较高营养价值。然而,柑橘果实采后容易发生腐烂、失水、营养损失和病害,导致果实品质劣变,商品价值降低。本文就柑橘果实采后外观色泽,果实水分,果肉糖、酸、维生素C含量变化,果实病害青霉病、褐斑病、枯水病、油斑病发生,以及低温贮藏、热处理、短波紫外线(UV-C)照射、化学保鲜剂、生物技术保鲜等保鲜技术的研究进展进行综述,为提高柑橘保鲜效果、保持柑橘果实采后品质、延长果实保鲜期提供科学依据与生产实践指导。     

Regulative Systems in the Developing Citrus Fruit I. The Hormonal Balance in Orange Fruit Tissues

The regulative systems of auxins, gibberellin-like substances and their inhibitors in citrus fruit were studied. Masking caused by a high content of inhibitors was eliminated by using a refined method of solvent partition. Considerable amounts of auxins and gibberellin-like substances were detected in all stages of fruit development. The auxin system of the citrus fruit is highly complex and consists of various elements which undergo dynamic changes throughout the growth period. The identity of the auxins was studied using IAA-2-¹⁴C, and 88% of the radioactivity specifically migrated into the etheric pH 6.0 fraction. Although the prominent zones of promotion do not coincide with IAA, it can be concluded that the auxin promoters are probably not the “citrus auxin”. Abscisic acid-like inhibitors were found to accumulate in the external layers of the fruit, increasing in content as time advances.     

A label-free differential quantitative mass spectrometry method for the characterization and identification of protein changes during citrus fruit development

Background

Citrus is one of the most important and widely grown commodity fruit crops. In this study a label-free LC-MS/MS based shot-gun proteomics approach was taken to explore three main stages of citrus fruit development. These approaches were used to identify and evaluate changes occurring in juice sac cells in various metabolic pathways affecting citrus fruit development and quality.

Results

Protein changes in citrus juice sac cells were identified and quantified using label-free shotgun methodologies. Two alternative methods, differential mass-spectrometry (dMS) and spectral counting (SC) were used to analyze protein changes occurring during earlier and late stages of fruit development. Both methods were compared in order to develop a proteomics workflow that could be used in a non-model plant lacking a sequenced genome. In order to resolve the bioinformatics limitations of EST databases from species that lack a full sequenced genome, we established iCitrus. iCitrus is a comprehensive sequence database created by merging three major sources of sequences (HarvEST:citrus, NCBI/citrus/unigenes, NCBI/citrus/proteins) and improving the annotation of existing unigenes. iCitrus provided a useful bioinformatics tool for the high-throughput identification of citrus proteins. We have identified approximately 1500 citrus proteins expressed in fruit juice sac cells and quantified the changes of their expression during fruit development. Our results showed that both dMS and SC provided significant information on protein changes, with dMS providing a higher accuracy.

Conclusion

Our data supports the notion of the complementary use of dMS and SC for label-free comparative proteomics, broadening the identification spectrum and strengthening the identification of trends in protein expression changes during the particular processes being compared.