坡柳(Dodonaea viscosa L.)丛枝植原体新病原的分子鉴定

从四川攀枝花芒果园中表现为丛枝、小叶和黄花等症状的坡柳植株发病样品中,利用植原体16S rDNA基因的通用引物R16m F2/R16m R1和R16F2n/R16R2,对发病植株总DNA进行巢式PCR检测,同时设计植原体抗原膜蛋白基因（AntMP）的保守引物AntMP-F/AntMP-R进行PCR验证。结果显示,坡柳样品巢式PCR的第一轮、第二轮DNA条带大小分别为1 400 bp和1 200 bp左右,经NCBI序列相似性比较均为植原体16S rDNA序列,Gen Bank登录号为KT957205和KT957206;PCR结果显示抗原膜蛋白基因大小约600 bp,与目标基因大小一致。将测得的16S rDNA基因序列与Gen Bank数据库中登录的16SrⅠ～ⅩⅤ组植原体16S rDNA序列进行同源性比对,构建系统进化树,结果显示四川坡柳丛枝植原体（DOVI-SC）属于16SrⅠ组（即翠菊黄花组）,与已报道的5个16SrⅠ组（AY101386,AY566302,AY389822,L33760和KP662119）同属一个组。利用植原体亚组分类鉴定软件iPhy Classfier对获得的2条植原体16S rDNA序列进行虚拟RFLP分析,结果显示KT957205,KT957206与16SrⅠ-B亚组洋葱黄化植原体（NC-005303）相似度分为1.0、0.97,归属于16SrⅠ-B亚组。本研究对引起四川坡柳丛枝的植原体病原进行检测,为坡柳植原体病害的早期诊断、快速检测以及预防措施制定提供科学线索。

Responses of Dodonaea viscosa growth and soil biological properties to nitrogen and phosphorus additions in Yuanmou dry-hot valley

Nitrogen(N) and phosphorus(P) are limited nutrients in terrestrial ecosystems, and their limitation patterns are being changed by the increase in N deposition. However, little information concerns the plant growth and the soil biological responses to N and P additions among different soils simultaneously, and these responses may contribute to understand plant-soil interaction and predict plant performance under global change. Thus, this study aimed to explore how N and P limitation changes in different soil types, and reveal the relationship between plant and soil biological responses to nutrient additions. We planted Dodonaea viscosa, a globally distributed species in three soil types(Lixisols, Regosols and Luvisols) in Yuanmou dry-hot valley in Southwest China and fertilized them factorially with N and P. The growth and biomass characters of D. viscosa, soil organic matter, available N, P contents and soil carbon(C), N, P-related enzyme activities were quantified. N addition promoted the growth and leaf N concentration of D. viscosa in Lixisols; N limitation in Lixisols was demonstrated by lower soil available N with higher urease activity. P addition promoted the growth and leaf P concentration of D. viscosa in Luvisols; severe P limitation in Luvisols was demonstrated by a higher soil available N: P ratio with higher phosphatase activity. Urease activity was negatively correlated with soil available N in Nlimited Lixisols, and phosphatase activity was negatively correlated with soil available P in P-limited Luvisols. Besides, the aboveground biomass and leaf N concentration of D. viscosa were positively correlated with soil available N in Lixisols, but the aboveground biomass was negatively correlated with soil available P. Our results show similar nutrient limitation patterns between plant and soil microorganism in the condition of enough C, and the nutrient limitations differ across soil types. With the continued N deposition, N limitation of the Lixisols in dry hot valleys is expected to be alleviated, while P limitation of the Luvisols in the mountaintop may be worse in the future, which should be considered when restoring vegetation.

Isoprenylated flavonoids and clerodane diterpenoids from Dodonaea viscosa

Phytochemical investigation of the aerial parts of Dodonaea viscosa led to the isolation of six new compounds including four isoprenylated flavonoids,dodovisones A-D(1-4),and two clerodane diterpenoids,dodovislactones A and B(5 and 6).Their structures were established by extensive spectroscopic analysis.

Cardioprotective effect of bioassay-guided fractions of Cleome viscosa methanolic extract in streptozotocin-induced diabetic rats

Objective:To evaluate the cardioprotective effect of bioassay-guided isolated fractions of Cleome viscosa methanolic extract in streptozotocin-induced diabetic rats.Methods:Total phenolics,flavonoids,and in vitro antioxidant activities of the methanolic extract of Cleome viscosa were evaluated.The FD-40 fraction from this extract was further evaluated for antihyperglycemic efficacy(insulin and HbA1c),antioxidant activity,and cardioprotective effects(creatine kinase-MB,lactate dehydrogenase,and histopathology)in streptozotocin-induced diabetic rats.In silico studies were also conducted to assess the bioactivity of FD-40.Results:Cleome viscosa methanolic extract exhibited the highest antioxidant activity in DPPH,ABTS,H2O2,and FRAP assays compared to other extracts.Treatment with FD-40(40 mg/kg b.w.)isolated from this extract normalized blood glucose,insulin,HbA1c,creatine kinase-MB,and lactate dehydrogenase levels in diabetic rats.It also significantly reduced oxidative stress by increasing antioxidant enzymes,decreasing lipid peroxidation as well as restoring the levels of ascorbic acid and glutathione.Histological study demonstrated that FD-40 treatment improved cardiac structure in diabetic rats.Molecular docking analysis revealed that phytocompounds from FD-40 had strong binding affinities with cardiac markers and oxidative enzymes.Hexose(5TMS)demonstrated greater binding affinity with xanthine oxidase and lactate dehydrogenase.Conclusions:FD-40 of Cleome viscosa methanolic extract exhibits significant cardioprotective effects in diabetic rats by regulating cardiac markers and reducing oxidative stress.The underlying mechanisms need to be elucidated in the future.

Effects of High Temperature Treatment on Seed Germination of Dodonaea viscosa(L.) Jacq

Seeds of Dodonaea viscosa （L.） Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and 100℃ respectively before germination to study impacts of high temperature treatment on their generation rate and to further discuss the roles of fire during the process of vegetation formation in dry and hot valley areas of China. The results show that when the temperature was higher than 40 ℃, the germination rate of D. viscosa seeds was significantly higher than that of the control group, and the heat shock effect was apparent. The germination rate was the highest when the seeds were treated at 80 ℃ for 10 min, reaching 63.00%±2.55%. There was still a significant heat shock effect on the D. viscosa seeds which were stored for one year. In comparison with the conventional method of soaking seeds in hot water, the germination rate of D. viscose seeds which were treated at high temperature before germination increased significantly.

光照和水分处理下坡柳幼苗的生理响应

为探讨坡柳(Dodonaea viscosa)在珊瑚砂环境的适应能力,设置全光、遮阴、黑暗3个光照处理,并采用梯度控水法设置正常控水、中度胁迫、重度胁迫3个水分梯度,对坡柳幼苗在光照和水分双因素处理下抗逆生理指标的变化进行了研究。结果表明,干旱胁迫和光照控制及其交互作用均对坡柳幼苗的丙二醛(MDA)、可溶性蛋白(SP)和脯氨酸(Pro)含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性有显著影响(P<0.05);遮阴和黑暗处理的MDA含量维持在较低水平;黑暗条件下SOD活性随胁迫程度增加而升高;全光和正常控水下POD活性最高;随光照强度减弱,CAT活性逐渐升高;遮阴和水分重度胁迫下SP含量最高,遮阴和水分中度胁迫Pro含量最高。因此,光照和水分对坡柳幼苗生长具有交互作用,在特殊生境生态修复实践中,给予坡柳幼苗适当遮阴的同时应保证适当水分有利于幼苗生长。

A new antimicrobial compound from the leaves of Dodonaea viscosa for infectious diseases

The main aim of this research work was to isolate and characterize the antimicrobial compounds that can be extracted from the leaves of Dodonaea viscosa(D.viscosa)and to assess their antimicrobial potency by established in-vitro agar diffusion method.The methanol extract was liquefied and fractioned by using a separatory funnel and organic solvents having different polarities.The agar diffusion technique was used to assess the antimicrobial potency of extracts and pure compounds against 5 g(+and-)microbial strains.Antimicrobial potency results showed that all extracts and isolated pure compounds provided significant antimicrobial potency against the applied microbial strains.The highest activity chloroform extract was analysed by column chromatography(CC)for the isolation of antimicrobial compounds.The structure of the isolated compounds was characterized based on 1D,2D NMR and MS spectra.In conclusion,purest compounds might be useful as a remedy for infectious diseases.

车桑子种子抗逆生理学特性及其对天然更新的影响

车桑子[Dodonaea viscosa（L.）Jacq.]是干热河谷植被重要的优势种或常见种。通过模拟金沙江干热河谷典型地区元谋盆地4月气候条件下,研究了车桑子种子的活力散失机制及其有关生理生化变化情况,并对车桑子天然群落的自然更新状况进行了调查。结果表明,随着高温干旱处理时间延长,种子活力不断降低,相对电导率、MDA含量呈持续上升趋势;呼吸强度、SOD活性、POD活性、CAT活性、可溶性糖含量呈单峰曲线变化;膜保护酶系统活力降低和保护性物质含量减少是造成种子活力下降的主要因素;实验处理的第12-18 d是车桑子种子抵御逆境的临界期;每年3月下旬至4月上、中旬,应采取人工辅助措施来提高其种子的天然更新能力。

云南热区坡柳对立地因子的生长响应

为了探讨不同立地因子对热区坡柳(Dodonaea viscosa L.)生长特征的影响,确定影响坡柳生长主导因子,在对坡柳在云南热区的资源分布进行初步踏查的基础上,选择14个地区开展了坡柳株高、地径、冠幅及生物量的调查,并进行了统计分析。结果表明:部分地区坡柳生长差异显著,其中大姚地区生物量最高,达到14.14 t·hm-2;低海拔区坡柳平均地径、平均株高及生物量均大于高海拔地区,分别为18.28 mm、179.16 cm和8.94 t·hm-2,但海拔高度对坡柳生物量及生长特征的影响未达到显著水平;坡柳总生物量、平均地径和平均株高均随坡位变化自下而上逐渐减少,下坡位生物量最大,达到10.01 t·hm-2,且上坡位生物量、平均地径及平均株高显著低于中坡位、下坡位(P<0.05);坡向对坡柳生长影响不明显,但是阴坡地段坡柳的生长指标平均地径、平均株高和总生物量都要优于阳坡地段。因此,可以认为影响坡柳生长的主导立地因子是坡位,坡柳最适宜的立地条件为低海拔,下坡位和阴坡。

干旱胁迫对坡柳等抗旱树种幼苗膜脂过氧化及保护酶活性的影响

以金沙江干热河谷主要树种坡柳、银合欢、山毛豆实生幼苗为材料,通过盆栽苗自然干旱胁迫,同时以浇水处理为对照,研究了干旱胁迫对坡柳、银合欢、山毛豆3个树种丙二醛含量、膜相对透性及保护酶活性的影响。结果表明,干旱胁迫下3个树种幼苗的细胞膜透性、MDA及SOD,POD酶活性都发生了变化,只是变化的幅度和进程不同。干旱胁迫对银合欢膜系统损伤生成的主要降解产物不是MDA;山毛豆清除活性氧毒害作用主要不是通过SOD和POD的作用;通过叶片相对保水力测定及膜透性、MDA相对含量、酶活性变化情况的分析,3个树种中坡柳耐旱性最强,其次为银合欢,山毛豆居后。

坡柳皂苷对大菜粉蝶生长发育的抑制活性

采用浸渍叶碟饲喂法测定了坡柳皂苷对大菜粉蝶的生物活性。结果表明：用500、1625、2750、3875和5000μg／mL的坡柳皂苷处理24h后，对大菜粉蝶4龄幼虫生长发育的抑制率分别为14．47％、31．54％、49．70％、62．48％和79．94％，处理48h后的抑制率分别为2．72％、39．26％、54．82％、70．53％和86．39％；坡柳皂苷对大菜粉蝶4龄幼虫具有显著的拒食活性，供试5种浓度下处理24h后，拒食率分别为30．21％、40．62％、54．33％、72．47％和84．84％，48h后的拒食率为4．4％～86．67％；5000I,zg／mL处理14d后，幼虫化蛹率为32％．显著低于对照组（72％）；供试5种浓度坡柳皂苷处理23d后，蛹的羽化率分别为56％、44％、44％、36％和32％，均低于对照组（64％）。研究表明，坡柳皂苷对大菜粉蝶生长发育、取食及化蛹均有明显的抑制作用。

干旱胁迫下3树种苗木叶片相对含水量、质膜相对透性和脯氨酸含量的变化

以金沙江干热河谷主要造林树种坡柳、银合欢和山毛豆的苗木为实验材料,通过盆栽苗自然干旱胁迫,同时以浇水处理为对照,探讨了干旱胁迫下3树种苗木叶片的相对含水量、质膜透性以及脯氨酸含量的变化情况。结果表明,干旱胁迫后,3树种苗木叶片的相对含水量、质膜相对透性以及脯氨酸含量都发生了变化,只是变化的幅度和进程不同。经三项生理指标的综合分析并结合3树种的自然表现,得出坡柳具有较强的抗旱能力,其次为银合欢,最后是山毛豆。

不同环境条件对车桑子萌发的影响

以车桑子(Dodonaea viscose(L.)Jacq)种子为实验材料,置入光照气候箱实培养,研究不同浸种方式(40℃温水、0.3%高锰酸钾溶液、不浸种)、温度处理(15、20、25、30℃恒温和18～25℃变温)和贮藏时间(11、15、19个月和23个月)对车桑子种子萌发的影响,结果表明:3种浸种方式下的萌发率差异不显著;在贮藏时间实验中,萌发率先升后降,在贮藏19个月时达到最高,与其他3次实验均呈现显著性差异;温度处理中,18～25℃变温处理萌发率比其他4次实验显著提高,20℃以上适合车桑子种子萌发。

云南干热河谷区裸地植被恢复过程中车桑子的种群特征

本研究采用野外调查和室内分析相结合的方法,研究了云南金沙江干热河谷区车桑子自然恢复种群的种群空间分布格局、种群密度、年龄结构以及车桑子的性别比例和生长速率等特征。结果表明:1车桑子种群随着树龄增加具有从聚集分布格局转变为均匀分布格局的趋势;2车桑子的年龄结构为一个金字塔形,为一个增长型种群,说明车桑子种群更新对该地区的干热气候具有较强适应性;3车桑子高生长速率和径向生长速率达到14.38和2.46 mm·a^(-1),萌蘖数达到5.37,具有速生性;4首次发现车桑子植株具有年际的性别转换现象。上述研究结果说明车桑子能够很好的适应干热河谷区的环境条件,是该地区植被恢复的优良材料。本研究还能为该地区车桑子种群的科学管理提供部分理论支撑。

瑞香狼毒和坡柳提取物对小菜粉蝶幼虫的拒食活性测定

瑞香狼毒乙醇提取物对小菜粉蝶4龄幼虫24h选择拒食作用的拒食中浓度(AFC50)为219.6mg/L;完全拒食作用的AFC50为1246.4mg/L;坡柳乙醇提取物对小菜粉蝶4龄幼虫24h选择拒食作用的AFC50为691.6mg/L,完全拒食作用的AFC50为398.0mg/L.

云南干热河谷水库气候效应对车桑子幼苗生长发育的影响及其作用机制

干热河谷地区水电站建设对当地植被的潜在影响是一个值得关注的生态学问题。车桑子是当地植被灌木层的主要成分,开展水库气候效应对车桑子生长、发育影响的研究具有现实价值。以车桑子的实生幼苗为材料,将土壤含水量控制为13%、7%和1.5%,空气湿度控制为50%、65%和75%,从幼苗生长、构件发育、根系发育、生物量分配等方面研究了降水减少和大气湿度增加的气候效应对车桑子的影响,通过叶绿素含量、Fv/Fm、丙二醛(MDA)含量和叶片可溶性糖含量等指标,从光合系统特性、膜质过氧化和渗透调节3个方面研究了车桑子的受损与适应机制。结果表明,土壤干旱能够抑制车桑子幼苗高生长和根系发育的各项指标,并促进生物量向根系分配;当大气湿度增加时,幼苗高生长和根长虽呈增加趋势,但生物量积累、根系发育指标及RMR却具有单峰效应,显示空气湿度过高时对其生长发育具有抑制作用。综合而言,由于大气湿度增加能够部分补偿土壤的干旱效应,干热河谷区水库建设的气候效应不会对车桑子幼苗的生长和发育产生重要影响。结果还表明,土壤干旱和大气湿度变化对叶绿素含量无影响,土壤水分胁迫和空气湿度下降导致Fv/Fm显著下降,说明光合电子传递链受损是车桑子光合抑制的主要原因;土壤水分胁迫导致MDA含量升高,说明细胞膜质过氧化是车桑子幼苗受损的重要机制;而土壤干旱导致叶片可溶性糖含量升高,说明车桑子幼苗具有较好的渗透调节机制。研究结果对评估干热河谷区水电站建设对植被的影响具有参考价值。

坡柳皂苷对马铃薯块茎蛾产卵选择性的影响研究

为探明坡柳皂苷对马铃薯块茎蛾产卵行为的影响,以开发生物农药,在室内采用选择性产卵实验方法分别测定了5种不同质量浓度的坡柳皂苷对马铃薯块茎蛾产卵选择性的影响。结果表明:从产卵量来看,各处理组与对照之间差异极显著,其中10.000g·L-1处理组与对照的落卵量差别较大、卡方值达到131.120,0.080g·L-1处理组次之、卡方值为92.395,2.000g·L-1处理组与对照的落卵量差别较小、卡方值仅为24.599;从驱避效果来看,当坡柳皂苷浓度为10.000g·L-1、0.080g·L-1时驱避效果较好,驱避引诱指数分别为0.1891、0.1881,但是当坡柳皂苷浓度为0.400g·L-1时,无驱避效果,驱避引诱指数为-0.1056,其它处理组驱避效果较弱;从整体上来看,坡柳皂苷对马铃薯块茎蛾产卵有驱避作用;坡柳皂苷对马铃薯块茎蛾的交配影响较小,0.016g·L-1、0.080g·L-1、0.400g·L-1、2.000g·L-1、10.000g·L-1处理组的交配率分别为60.00%、67.50%、67.50%、67.50%、72.50%。表明,坡柳皂苷对马铃薯块茎蛾具有一定的产卵驱避作用,有望成为一种绿色环保的马铃薯块茎蛾产卵驱避剂。

坡柳皂苷对粘虫生长发育的活性研究

研究了坡柳皂苷对粘虫生长发育的活性。采用浸渍叶碟法,分别测试了5个质量分数处理对粘虫的生物活性。结果表明:坡柳皂苷对粘虫具有较好的发育抑制,且随浓度的增大而提高。24 h后2 000,3 000,4 000,5 000,6 000μg/mL坡柳皂苷处理对粘虫4龄幼虫的发育抑制率分别为24.36%、37.81%、49.38%、54.93%、71.30%,48 h后为15.14%、44.91%、58.66%、61.42%、68.74%;上述5种处理24 h后的拒食率分别为8.72%、26.74%、41.53%、55.92%、64.39%,处理48 h后拒食率分别为4.08%、30.18%、57.66%、60.14%、68.03%;13 d后,6 000μg/mL处理幼虫的化蛹率为32%,显著低于CK(92%);上述5种处理24 d后蛹的羽化率分别为56%、48%、36%、32%、20%;40 d后上述5种处理卵的孵化率分别为36.74%、23.61%、7.76%、5.57%、5.46%。因此,坡柳皂苷对粘虫幼虫的生长发育、取食、化蛹和蛹的羽化、卵的孵化具有一定程度的抑制效果。

坡柳种子提取物对4种植物病原真菌的抑菌作用

采用菌落直径法进行抑菌试验,研究了坡柳种子提取物对几种植物病原真菌菌落生长的影响,研究结果表明:乙醇提取物抑菌效果最好。EC50的测定表明,乙醇提取物对燕麦镰刀菌的抑制中浓度(EC50)最低为0.43 g/L。坡柳种子乙醇提取物可为开发新的杀菌剂提供有价值的参考。

车桑子和白刺花种子质量分级标准初步研究

车桑子(Dodonaea viscosa(L.)Jacq.)和白刺花(Sophora viciifolia Hance)是我省飞机播种造林的主要树种。由于在判定这两个树种种子质量时既无国家标准,又无地方标准作为依据,因此给种子质量评价和监督造成一定困难。本文通过对2001-2005年四川省林木种苗质量监督检测中心及凉山州林业种子种苗管理站车桑子和白刺花种子样品检测数据进行处理与分析,初步提出这两个树种种子质量分级标准的指标体系。