柬埔寨龙血树褐斑病的病原鉴定及其培养条件分析

[目的]柬埔寨龙血树为我国各省市广泛栽培的室内观叶植物,近年来普遍发生叶部病害影响其观赏价值。2011年8月至2016年12月,在云南省蒙自市、新疆乌鲁木齐的柬埔寨龙血树发现一种叶部初期褪绿逐渐变为灰褐色凹陷最后暗褐色枯死的褐斑病。为了确定其病原菌种类和发病条件,进行病原菌鉴定及培养条件测试。[方法]采用在云南蒙自、新疆乌鲁木齐采集的12份柬埔寨龙血树褐斑病病叶,开展了组织分离、致病性测试、形态学观察、分子鉴定与培养条件测试。[结果]从12份病叶分离到15株真菌,菌落中央产生黑色孢子,边缘白色,顶囊球形或近球形,直径38~45μm,分生孢子球形暗褐色,直径2~5μm,代表性菌株LZB-6、LZB-12经CaM或β-tubulin系统发育分析确定为塔宾曲霉;刺伤法接种14 d的龙血树叶片均发病,症状与田间一致,并能分离到菌落形态、分生孢子形态与原分离菌株一致的真菌,完成科赫法则验证确定为病原菌。培养条件测试表明,病原菌菌丝生长的适宜温度为22~34℃,最适宜温度为28℃,光照抑制菌丝生长,菌丝生长偏爱碱性环境,pH为7~10时,随着pH值升高生长速率仍在增加,最适宜碳源和氮源分别为甘露醇、明胶,菌丝致死温度为55℃10 min;产孢适宜温度为28~40℃,最适宜温度为32℃,光照抑制产孢,适宜产孢pH值为6~8,最适宜pH值为8,最适宜碳源和氮源分别为蔗糖、明胶,孢子的致死温度为60℃10 min。[结论]导致云南蒙自、新疆乌鲁木齐的柬埔寨龙血树褐斑病菌均为塔宾曲霉,除了光照和氮源之外,温度、pH值、碳源对菌丝生长和产孢的影响均不同,22~34℃时病原菌能较好的生长与产孢,应加强对柬埔寨龙血树褐斑病的防控。

Direct Regeneration of Inflorescence from Callus in Dracaena fragrans cv. Massangeana Hort.

以花叶千年木 (Dracaenafragranscv .MassangeanaHort.)的花被筒、花序分枝轴和花序轴为外植体成功地诱导了花序的直接再生。3种外植体首先在MS附加 1.0mg L 6_BA和 0 .5_0 .8mg L 2 ,4_D的培养基上诱导形成愈伤组织 ,然后转移到MS附加 0 .5mg L 6_BA和 0 .0 0 5～ 0 .5mg L 2 ,4_D的培养基上分别诱导了花序的直接再生。

Identification and rDNA-ITS Sequence Analysis of a New Anthracnose Pathogen of Dracaena fragrans in Yunnan Province

In this study, identification and rDNA-ITS sequence analysis of an anthracnose pathogen on Dracaena fragrans were carried out. [Method] D. fra-grans leaves with lesions were used as experimental materials to isolate anthrac-nose pathogen. Morphological observation, rDNA-ITS amplification and sequence analysis were performed to identify the pathogen strain. [Result] Caonidia of the iso-lated anthracnose pathogen were straight or curved, el iptic to crescent, with 2-5 oil droplets, 7.5-20 × 4.5-5 μm. According to molecular phylogenetic analysis, the iso-lated pathogen strain was identified as a new species, which was named Col-letotrichum dracaena-fragrantis sp. nov. [Conclusion] This study provided theoretical basis for the prevention and control of anthracnose.

Control of In Vitro Regeneration of Individual Reproductive and Vegetative Organs in Dracaena fragrans cv. massangeana Hort. Regularities of the Direct Regenerationof Individual Organs In Vitro

Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangeana Hort. During the regeneration of these individual organs some regularity phenomena were observed. Firstly, the kind range of the individual organs, which are directly regenerated in vitro, is in close relationship to the differentiated stages of the organs used for explant excision during plant ontogeny. The explants excised from the epigeous organ that is differentiated at some stage (stage A) during plant ontogeny must be able to separately regenerate all of those individual epigeous organs: ones differentiated slightly later than the stage A, ones differentiated at the stage A and all ones differentiated earlier than the stage A. Secondly, within this range which kind of organ is regenerated depends on the exogenous auxin concentrations in medium. With the gradual increase of 2,4-D concentration from 0.005 mg/L to 0.5 mg/L, the kinds of regenerated organs will change by the order as follows: vegetative bud, inflorescence, inflorescence branch, flower bud, tepal. These regularities will be able to be used for inducing the direct regeneration of a given epigeous organ in angiosperms.

不同水分条件对海南龙血树幼苗表型可塑性及生态适应性的影响

通过盆栽试验探讨濒危植物海南龙血树幼苗对水分响应的表型可塑性,分析其生态适应性。结果表明,海南龙血树幼苗对水分的响应主要在形态指标和生物量方面,除了比叶面积、叶片长宽比和株高外,其他指标均达到显著水平(P<0.05);生物量分配主要与根部性状相关,幼苗叶绿素和类胡萝卜素含量在各处理间无显著差异(P>0.05)。海南龙血树幼苗能够充分利用水分资源,在雨季快速生长,并将更多的生物量分配给根部,有利于度过雨季后严峻的干旱季节。海南龙血树幼苗对水分响应的生存策略具有很强的生态适应性。

龙血树组织诱导快速繁殖技术研究

【目的】探究不同消毒方法和激素配比对龙血树组培快繁技术的影响,为建立龙血树组培快繁体系提供参考。【方法】以‘太空’和‘68#’2个龙血树品种的外植体为试材,探讨不同的灭菌时间、激素配比及浓度对龙血树不定芽诱导、增殖和生根的影响。【结果】研究表明龙血树无菌材料的获得,适宜采用带顶芽茎段,先用75%酒精消毒20 s,再用0.1%升汞溶液消毒8 min,消毒效果最佳。MS+5.0 mg/L 6-BA+3.0 g/L花宝为最佳不定芽诱导培养基;MS+2.0 mg/L 6-BA+0.1 mg/L NAA为最佳增殖培养基,太空和68#增殖系数分别达5.35和4.87;MS+1.0 mg/L NAA为最佳生根培养基,太空和68#的生根率均高于99%,生根数分别达到9.2和11.2条。【结论】建立以带顶芽茎段为外植体的龙血树组织培养快繁体系,为龙血树工厂化生产和遗传转化等研究奠定良好基础。

Dracaenoside A and B, New C-22 Steroidal Lactone Glycosides from the Stem of Dracaena cochinchinensis

Two new C-22 steroidal lactone glycosides, named dracaenoside A and B were isolated from the methanol extract of the fresh stem of Dracaena cochinchinensis. Their structures were established as (20S)3b,14a,16b-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-a- L-rhamnopyranosyl (1→2)[ a-L-rhamnopyranosyl (1→4)]-b-D-glucopyranoside and (20S)3b, 14a, 16b-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-a-L-rhamnopyranosyl (1→2) [b-D-glucopyranosyl(1→3)]-b-D-glucopyranoside by means of 2D NMR spectral and chemical methods. It is the first time that steroidal lactone glycosides were isolated from the genus Dracaena.

Larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri Gagnep against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles minimus mosquito vectors

Objective:To evaluate the larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri endocarp against Aedes aegypti,Aedes albopictus,Culex quinquefasciatus,and Anopheles minimus mosquitos.Methods:Larvicidal activity was tested according to World Health Organization standard protocol.The third-stage larvae of each mosquito species were exposed to various concentrations of Dracaena loureiri crude extract and six groups of Dracaena loureiri fractionated extracts(RC-DT 009-014).Larval mortality rates were observed after 24 h and48 h of exposure.Then,a computerized probit analysis of the mortality data was performed to determine lethal concentration 50(LC_(50))and lethal concentration 90 values.Results:Anopheles minimus larvae(24-h LC_(50)77.88 mg/L)had the highest susceptibility to crude extract,whereas others(Aedes aegypti,24-h LC_(50)224.73 mg/L;Aedes albopictus,24-h LC_(50)261.75 mg/L;and Culex quinquefasciatus,24-h LC_(50)282.86 mg/L)were significantly less susceptible.The most effective groups of fractionated extracts were RC-DT 012 and RC-DT 013.The mosquito species most susceptible to fractionated extracts was Culex quinquefasciatus,with 24-h LC_(50)values of 0.66 and 0.94 mg/L for RC-DT 012 and RC-DT 013,respectively.Conclusions:The larvicidal activity of fractionated extracts is more effective than that of crude extract against all tested mosquito species.For the most effective alternative larvicide,purification and a phytochemical constituent analysis must be performed.

Effects of Dracaena arborea(Dracaenaceae) on sexual dysfunction in 4 weeks hyperglycemic male rats

Objective:To investigate the effects of Dracaena arborea(D.arborea) on the sexual behavior parameters in experienced type-1 diabetic rats.Methods:Aqueous and ethanol(100 and 500mg/kg respectively)extracts of dried root barks of D.arborea.sildenafil citrate(1.44 mg/kg),trimethylamine-N-oxide(TMAO,20 mg/kg)and distilled water(110 mL/kg.were orally administered to 4 weeks streptozolocin-induced diabetic rats.Mount latency and frequency(ML.MF),intromission latency and frequency(IL,IF) and post-ejaculatory interval(PEI) were measured by ejaculating series during 90 min once a week for 4 weeks.Glycemia was determined at the beginning and at the end of the treatment Results:D.arborea did not show any major antihvperglycemic effects.Compared to the control group,a significant(P<0.05-0.001)increase in MF and IF was noticed in rats treated with sildenafil citrate(89.71% and 90.07% respectively),aqueous(500 mg/kg.88.08%and 88.749;respectively) and ethanol(100 mg/kg;89.53%and 89.17respectively) extracts of D.arborea after two weeks(series 1) of treatment.ML,IL and PEI were significantly(P<0.05-0.001) decreased after 4 weeks of daily treatment[sildenafil citrate(96.31.96.31%and 34.98%),and D.arborea aqueous 500 mg/kg(94.33.94.33% and 66.609;i and ethanol extracts 100 mg/kg(96.98.97.089;and 64.26%)].Conclusions:These aphrodisiac potentials of D.arborea in experienced diabetic rats could be due to the antioxidant and androgenic properties of phenols,flavonoids.saponins and sterols revealed in the plant extracts.

Flavonoid oligomers from Chinese dragon’s blood,the red resins of Dracaena cochinchinensis

A detailed chemical investigation of the red resins from Dracaena cochinchinensis(Chinese dragon’s blood)yielded five new flavonoid oligomers,named cochinchinenins D-H(1-5),together with a known biflavonoid,cinnabarone(6),and a mixture of two known biflavonoids,socotrin-4'-ol(7)and homoisosocotrin-4'-ol(8).Of these new compounds,1-3 were biflavonoids and 4 and 5 were triflavonoids.Their structures were determined on the basis of spectroscopic analysis.The isolated compounds were tested for cytotoxicity(Cdc25),antibacterial(PEPT)and antifungal(YNG)activities.

Larvicidal activity of endocarp and seed crude extracts of Dracaena loureiri Gagnep against Aedes aegypti(L.) mosquito

Objective: To evaluate the larvicidal activity of the ethanolic and aqueous extracts of the endocarp and seeds of Dracaena loureiri(D. loureiri) against the dengue mosquito vector, Aedes aegypti.Methods: Bioassays were performed by exposing late third-stage to early fourth-stage larvae of Aedes aegypti to various concentrations of the extracts from D. loureiri. The larval mortality was observed after 24-and 48-h exposure.Results: The larvicidal bioassay in this study demonstrated that the ethanolic endocarp extract was the most effective with the LC50 value of 84.00 mg/L after 24 h exposure and< 50 mg/L after 48 h exposure. Extracts from the other parts of the plant were significantly less effective as a larvicide.Conclusions: The ethanolic endocarp extract of D. loureiri demonstrated effective larvicidal activity. It is an alternative source for developing a novel larvicide for controlling this mosquito species.

Effects of the Incorporation of <i>Dracaena arborea</i>Roots Powder on Growth Performance and Some Haematological Parameters in Guinea Pigs (<i>Cavia porcellus</i>)

The present study was assigned to evaluate the Effect of Dracaena arborea roots powder in ration on growth performances and some hematological parameters in the guinea pig on diet supplemented with graded levels of incorporation. A total of 40 guinea pigs weaned of local breed and aged 3 weeks were divided into 4 identical batches. Each of the groups was randomly assigned one of 4 rations containing different levels of the powder from Dracaena arborea (Da) roots: Da0;Da0.25;Da0.5 and Da0.75. The results at the 11th week of breeding showed that the highest intake (21.13 g/d) was obtained with the Da0.5 ration. The highest live weight (372.50 g) and total weight gains were obtained with the Da0.25 ration. In addition, the highest commercial (161.75 g) and conventional (307.75 g) carcass weights and large intestine length (99.5 cm) were obtained with the D0.25 ration. The highest values for granulocytes (0.250.103/μl), platelets (805.103/μl) and lymphocytes (6.92.103/μl) were respectively, obtained with the rations containing Da0;D0.5 and D0.75. In view of the above, Dracaena arborea roots powder can be used at a rate of 0.25% in the ration, to improve the productivity of the guinea pig (Cavia porcellus).

富贵竹标准化发展现状与建设对策分析

当前富贵竹的标准体系不完善,标准较少,严重阻碍了我国富贵竹产业的发展。文章通过花卉标准和富贵竹标准结合进行分析,又通过对湛江麻章区具体富贵竹生产加工企业的走访调研,得出富贵竹标准发展的现状和问题,并结合现代富贵竹生产的内容情况提出相应对策。

剑叶龙血树4CL基因的克隆及其功能预测

目的:对剑叶龙血树4CL家族基因进行克隆及功能预测,筛选出可能参与黄酮类生物合成相关的4CL基因,为深入阐述龙血竭的形成机制奠定基础。方法:在前期转录组测序数据的基础上,初步筛选4CL家族基因,并对其进行基因克隆及功能预测,筛选可能与黄酮类及木质素类化合物合成相关的4CL基因;以剑叶龙血树组培苗为研究对象,对其进行过氧化氢、茉莉酸、水杨酸等胁迫处理,实时荧光定量聚合酶链式反应(qRT-PCR)分析不同胁迫处理条件下4CL基因的相对表达变化规律。结果:在剑叶龙血树转录组数据库中共注释得到6个4CL基因并成功完成其基因克隆;其中3个基因(Dc4CL1、Dc4CL2和Dc4CL3)在龙血竭形成过程中呈现差异表达,Dc4CL1基因和Dc4CL2基因的表达模式与木质素类化合物生物合成的关键酶基因表达变化趋势一致,而Dc4CL3基因的表达模式与黄酮类化合物生物合成的关键酶基因表达变化趋势一致;系统发育分析结果显示,Dc4CL1和Dc4CL2属于Ⅰ类4CL基因,而Dc4CL3基因属于Ⅱ类4CLs基因;胁迫处理结果显示,Dc4CL均有差异性表达变化,其中Dc4CL3基因的相对表达量显著高于其他Dc4CL基因。结论:对龙血竭形成过程中起关键催化作用的4CL基因进行初步的筛选,其中Dc4CL1基因和Dc4CL2基因(Ⅰ类)可能主要参与木质素类化合物的生物合成,Dc4CL3基因(Ⅱ类)可能是龙血竭形成过程中黄酮类化合物生物合成的关键催化酶基因。

海南长花龙血树叶的主要蛋白鉴定及其功能分析

长花龙血树是海南黎族药用植物之一,为深入研究开发长花龙血树叶的价值和功能,针对其含有的植物蛋白种类,采用基于BPP+酚提取法的双向电泳技术,通过优化实验条件,对海南产长花龙血树叶进行蛋白质的提取分离,获得蛋白指纹图谱;利用Image Master 5.0软件分析凝胶图像筛选出高表达蛋白;再利用基质辅助激光解析电离飞行时间质谱(Matrix-assisted laser desorption ionization time-of-flight mass spectrometry,MALDI-TOF-MS)技术对这些蛋白酶解产物进行质谱鉴定,最后通过生物信息学手段进行蛋白功能初步分析。研究结果表明,海南长花龙血树叶有60个高表达的蛋白,通过生物质谱鉴定出ATP合酶、核酮糖二磷酸羧化酶大链、叶绿体等45个蛋白,涉及长花龙血树叶生长、发育及植物抗逆等多种功能。本研究为进一步开发利用长花龙血树叶中的植物蛋白提供理论依据,对理解海南岛的生态系统服务和生态效益也具有一定的理论和实践意义。

不同连作年限富贵竹根际土壤理化性状分析

为揭示连作对富贵竹根际土壤理化性状的影响,本研究以连作0年(CK)、3年、6年、9年、12年的富贵竹根际土壤为材料,分析连作年限对土壤理化指标的影响。结果表明:随着连作年限的增加,根际土壤容重逐渐增大,pH值逐渐降低,有酸化趋势;土壤EC值在30.33~58.02μS/cm之间,随着连作年限的增加,呈先降后升再降的趋势,在连作9年时达到最大值;根际土壤有机质含量随着连作年限的增加呈下降趋势,其中连作12年的土壤有机质含量仅为CK的58.55%;氮、磷、钾含量会受到人工施肥等措施的影响,在小幅波动中维持相对均衡;而根际土壤交换性钙、镁含量呈逐年降低趋势,且连续种植9年以上的土壤降低显著,可见富贵竹连作消耗Ca、Mg元素相对较多,建议加强科学施肥管理,维持土壤养分平衡,是避免土壤连作障碍的有效途径。

Examining the Effect of Hydroalcoholic Extract of Dracaena cinnabari on Sex Hormones and Ovarian and Uterine Tissues of Rats

Introduction: Dracaena cinnabari is considered a rich source of phytochemicals used widely in traditional medicine. In the present study, the effect of D. cinnabari hydraulic extract on the reproductive system of female rats was investigated. Methods: The samples were randomly divided into four groups(six samples in each group), including three treatment groups and one control group, and all samples were kept at the same conditions. Hydraulic extract of D. cinnabari and injected intraperitoneally daily for 10 days, while physiological serum was used for injection in to the control group. After 10 days of injection, estrogen and progesterone levels were measured by enzyme immunoassay technique. After dissection, the ovaries and uterine tissues were isolated for histological examination, and tissue changes were carefully examined. Results: The results revealed that the levels of estrogen and progesterone in experimental Groups 2 and 3 had a significant increase(P < 0.001). Regarding tissue changes, a significant increase was observed in epithelial thickness(P < 0.001), number of corpus luteum(P < 0.01), and Graafian follicle(P < 0.01) in doses of 100 and 150 mg/kg. Conclusions: Based on the results, it seems that D. cinnabari extract has an effect on the ovarian follicles.

Transient receptor potential vanilloid 1 involved in the analgesic effects of total flavonoids extracted from Longxuejie(Resina Dracaenae Cochinchinensis)

OBJECTIVE: To evaluate the analgesic effects of total flavonoids of Longxuejie(Resina Dracaenae Cochinchinensis)(TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1(TRPV1).METHODS: Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments in vivo were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by TFDB.RESULTS: Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion(DRG) neurons of rats and the half inhibitory concentration was(16.7 ± 1.6) mg/L.TFDB(2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and(0.02-2 mg per paw)reduced capsaicin-induced licking times of rats. TFDB(20 mg/kg) was fully efficacious on complete Freund's adjuvant(CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain rats.CONCLUSION: All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.

腔孢纲真菌的三个新种

在调查香龙血树Dracaena fragrans (L.)Ker-Ganl.的病害中，发现了腔孢纲真菌的3个新种,即：Phomopsis dracaenicola Z.D.Jiang, P.G. Xi et P.K.Chi，Bartalinia dracaenae P.G.Xi, Z.D.Jiang et P.K.Chi及Sphaeropsis dracaenae P.G.Xi et P.K.Chi, 模式标本保存在华南农业大学真菌标本室。

中药龙血竭原植物剑叶龙血树的形态组织学研究及所含树脂的分布和成分检测

目的:对剑叶龙血树进行系统的组织学研究及所含树脂的分布和成分检测研究,为进一步研究剑叶龙血树树脂形成的成因和机理提供参考依据。方法:采用彩色显微照相技术对剑叶龙血树含树脂茎和无树脂茎,以及根、茎皮、叶进行系统的组织学研究;同时用高效液相色谱仪将含树脂茎和无树脂茎的指纹图谱进行了比较。结果:阐明了含树脂茎的纵切结构以及叶的表面观特征;除了茎木质部导管和纤维中有树脂外,发现剑叶龙血树受到损伤之后在茎皮层薄壁细胞、根的髓部和木质部亦有树脂的分布;含树脂茎和无树脂茎的指纹图谱显示剑叶龙血树茎在形成树脂后的化学成分中出现了较多的黄酮类、茋类成分。结论:剑叶龙血树无分泌组织出现,树脂出现在非分泌细胞中,其树脂形成的机制需要进一步研究。