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1.
蓝果树和喜树的茎、叶解剖特征分析   总被引:1,自引:0,他引:1  
对蓝果树和喜树的茎、叶解剖结构进行研究的结果表明,蓝果树和喜树叶的解剖结构为典型的异面叶,叶表皮外具角质层,栅栏组织1层,排列紧密,海绵组织细胞间隙大;茎中维管束的大小及排列相似,茎中含有晶体,具有裂生型分泌道。蓝果树与喜树营养器官结构参数具有种间差异,蓝果树叶的栅栏组织发达,叶片较厚,主脉韧皮纤维发达;喜树茎的皮层存在环状厚壁组织,叶肉中存在晶体。  相似文献   

2.
半干旱黄土区沙棘的形态解剖学特性研究   总被引:4,自引:0,他引:4  
李代琼  梁一民  黄瑾  姜峻 《沙棘》2004,17(1):8-13
1994~2002年先后在黄土高原半干旱区的安塞、吴旗县进行了沙棘形态解剖学特性试验研究。结果表明:沙棘叶具发达的表皮毛、较厚的角质层和发达的栅栏组织细胞,对大气干旱有强的适应性。根的周皮薄壁组织发达,细胞和细胞间隙较大,持水力强。沙棘由于具耐旱和节水型御旱的形态解剖和水分生理生态学特性,使沙棘耐旱、抗寒、耐水湿,在干旱、半干旱地区适应性强,并具有较高的生态、经济效益。以上研究为沙棘在黄土高原半干旱区大面积荒山抗旱造林,经营管理提供了科学依据。  相似文献   

3.
山桃等3个树种叶片解剖结构的耐旱性特征研究   总被引:4,自引:1,他引:3  
采用石蜡切片法,对山桃、柄扁桃、蒙古扁桃3种植物叶的解剖结构进行了显微观察,选择叶片厚度、角质层厚度、栅栏组织厚度、海绵组织厚度、栅栏组织细胞长和宽为观测指标.结果表明:这3种植物叶片均具角质层且细胞外壁加厚;气孔位于下表皮且具有空下室;具粘液细胞、含晶细胞;栅栏组织细胞排列紧密,维管组织发达等抗旱解剖结构特征.利用隶属函数综合评价法对其耐旱性进行排序,结果为:柄扁桃>蒙古扁桃>山桃.  相似文献   

4.
印楝素A无细胞合成体系构建及其合成前体   总被引:1,自引:0,他引:1  
【目的】印楝素是一种植物源杀虫剂,印楝素A是印楝素的主要活性成分。本研究通过对印楝素A无细胞合成体系制备条件和反应条件的优化,以及印楝素A合成前体的筛选,探讨印楝素A的离体生物合成途径,以为指导构建印楝素异源生物合成平台,实现印楝素的异源生物合成奠定基础。【方法】通过对缓冲液类型、浓度、起始pH、提取时间及料液比进行单因素试验及正交试验优化,构建印楝素A无细胞合成体系;从反应终止试剂及稳定剂、反应温度、反应时间、底物浓度以及辅助因子5个方面优化无细胞合成体系的反应条件。利用印楝素A无细胞合成体系分别以2,3-环氧鲨烯、羊毛甾醇、大戟二烯醇、丁酰鲸鱼醇、nimbin、茄碱苷和脱乙酰茄碱苷为底物,以印楝素A相对产量为评价标准,探讨印楝素A合成前体。【结果】印楝素A无细胞合成体系的构建:以pH7.0的200 mmol·L~(-1) Tris-HCl缓冲液,按1∶20(g·mL~(-1))料液比加入印楝叶片,提取1 h。优化的印楝素A无细胞合成条件为:反应总体积800μL,其中含印楝无细胞提取物300μL(相当于印楝叶0.015 g),100μL 250μmol·L~(-1)的底物(鲨烯)和400μL含有1 mmol·L~(-1) Mg~(2+)、1 mmol·L~(-1) Mn~(2+)、0.1 mmol·L~(-1) ATP、0.1 mmol·L~(-1) NADPH~+和5 mmol·L~(-1)抗坏血酸的缓冲液,在30℃下反应60 min,迅速加入200μL乙酸终止反应。分别以2,3-环氧鲨烯、丁酰鲸鱼醇、大戟二烯醇、nimbin、茄碱苷和脱乙酰茄碱苷为底物,反应完成后,印楝素A含量均有不同程度的增加;羊毛甾醇抑制体系中印楝素A的合成。【结论】羊毛甾醇不是印楝素A的合成前体,2,3-环氧鲨烯和丁酰鲸鱼醇是印楝素A的前体,nimbin、大戟二烯醇、脱乙酰茄碱苷和茄碱苷极可能是印楝素A的合成前体,且茄碱苷位于合成途径较下游的位置。  相似文献   

5.
采用石蜡切片法观察了塔里木盆地的碱蓬属6种植物的解剖结构,表明碱蓬属6种植物具不同的适应盐生生境的结构特征:(1)星花碱蓬、平卧碱蓬与肥叶碱蓬表皮细胞外侧壁常外凸生长,五蕊碱蓬、硬枝碱蓬与高碱蓬外凸生长不明显;(2)碱蓬属6种植物叶肉为环栅型,特别的是平卧碱蓬、肥叶碱蓬与五蕊碱蓬表皮下分化出了一层不含或含极少叶绿肥体的贮藏组织;(3)硬枝碱蓬栅栏组织细胞的形态小、细胞的层数较多,而肥叶碱蓬叶肉栅栏不发达,分化出了大量的贮藏组织;(4)硬枝碱蓬与高碱蓬的主脉维管束内分化出了1层形成层而另外4种没有形成层.  相似文献   

6.
发展印楝 富民强州   总被引:2,自引:0,他引:2  
印楝是一种常绿乔木,胸径可达30~80厘米,树高可达20~30米。作为一种耐旱的树种,印楝在干旱和半干旱的地方比其他的速生树种要长得好。印楝能够适应不同的生长环境,它在气温高达49℃的环境中能够较好地生长,也能够经受得住0℃的低温气候。它可以在海拔1 500米的地带生存。在山高、坡陡、土瘦、干旱的荒山荒地种植印楝,可以减少水土流失,改善生态环境。印楝的经济价值较高,根、皮可治疗疟疾、糖尿病、胃病、溃疡等病;叶可作防腐、杀菌、驱虫、镇痛、免疫调节剂,可治疗眼病、皮肤病;子种可作通便、润肤、子宫刺激收敛剂;花用于滋…  相似文献   

7.
影响印楝素稳定性及其含量的主要因素   总被引:7,自引:0,他引:7  
印楝素的稳定性及其含量的高低受许多因素的影响。印楝素对光敏感,暴露在光下会逐渐失去活性;室温及低于20℃的贮藏温度有利于印楝素的稳定,而高于室内温度会加速印楝素的降解;印楝素在中性条件下比较稳定,室温条件下,在pH值为4~6的酸性水溶液中也稳定,但在碱性和强酸溶液中不稳定;中性有机溶剂对其稳定性有利。微生物的活动会加快印楝素的降解,不同的地理种源和种植土壤对印楝种实中印楝素的含量高低影响很大,在干季所结果实的种子中印楝素含量高于在雨季种植所结果实的种子。而不同组培条件对组培体的印楝素含量也会产生影响。  相似文献   

8.
采用组织离析法和石蜡切片法研究蜡梅营养器官解剖学结构的结果表明:蜡梅芽具有芽鳞;蜡梅具有典型的异面叶,表皮角质层较厚,表皮具有表皮毛,气孔多集中在下表皮,为平行列型;栅栏组织由两层细胞组成,栅栏组织与海绵组织厚度的比值高,主脉维管束呈列状排列,木纤维和韧皮纤维较发达;蜡梅根的初生木质部导管数量多、口径大,髓部为木质部占据;次生根周皮增厚;幼茎木质部含有较多的导管,茎中韧皮纤维和髓部发达;老茎的维管束紧密排列连成环状,茎的每个突起部位都有成团的韧皮纤维;蜡梅解剖结构特点说明腊梅与其山林干燥、寒冷的生长环境相适应,具有耐旱性及抗寒性。  相似文献   

9.
印楝原产于印-巴次大陆及南亚和东南亚的干旱地区,分布海拔范围一般为1000m以下,最高达1830m。印楝喜光照,幼苗不耐荫蔽;正常生长的年均温不低于20℃,常年极端低温大于0℃,对霜冻敏感;在年均降水量450~1200mm的地方生长最好,能耐受不足130mm的降水和较长的干季;对土壤类型要求不高,但在渗透性和排水性好的土壤中长势好;土壤肥力对印楝的生长比水分的供应更重要;不同地理种源的印楝生长差异很大;杂草对幼树影响很大,除草能促进其生长;印楝的活性成分提取物虽能防治多种病虫害,但仍有60多种害虫及某些病害为害它。  相似文献   

10.
印楝素和苦楝素对植物病原菌的抑制作用   总被引:12,自引:0,他引:12  
印楝(Azadirachta indica.A.juss)系楝科楝属乔木,被美国农业部誉为“可解决全球问题之树”。从印楝植株中发现了以印楝素(Azadirachtin)为主的80余种活性物质,可防治10目400余种农林、仓库和卫生害虫,是理想的生物杀虫剂。其杀真菌活性的研究在国内未见报道。本文选用4种植物病原菌,测定了其抑菌活性;并与另一种  相似文献   

11.
High antifeedancy and low toxicity of the plant preparation Neem (azadirachtin), on the gypsy moth, Lymantria dispar L. larvae were proved under laboratory conditions. A high index of Neem antifeedancy was confirmed in all tested concentrations. Under laboratory conditions the Neem had satisfying antifeedancy on Leptinotarsa decemlineata Say third instar larvae too. Field experiments also proved that the foliage protective effect of Neem was very significant. Experiments showed that some antifeedants or repellents, such as Neem, should control olygophagous (L. decemlineata, Coleoptera) insects as well as very polyphagous insects such as L. dispar (Lepidoptera). As a biological, plant-derived preparation, Neem could be suitable for integrated pest management (IPM) programs, especially in small orchards, parks, and tree rows in urban environments and on small private gardens.  相似文献   

12.
四种含笑叶解剖性状与抗旱性的研究   总被引:9,自引:1,他引:9       下载免费PDF全文
对2年生乐昌含笑、金叶含笑、阔瓣含笑和深山含笑等4种含笑叶片组织解剖性状的测定与盆栽抗旱性观测表明:供试树种间叶解剖性状在叶片厚度、角质层厚度、栅栏组织厚度、海绵组织的厚度、栅栏组织与海绵组织的厚度比、叶片结构紧密度、叶片结构疏松度和气孔密度等指标有显著差异;上表皮和下表皮厚度结构指标差异不显著.叶片厚度、角质层厚度、栅栏组织厚度、栅栏组织与海绵组织厚度的比值、叶片结构紧密度和气孔密度等值越大的含笑,受旱危害愈轻,其抗旱性就越强.叶片厚度、尤其是角质层的厚度和海绵组织厚度是评价供试含笑抗旱性的重要解剖指标.依据叶解剖性状结构指标,并结合盆栽试验旱害观测,供试树种的抗旱性大小为:阔瓣含笑>深山含笑>金叶含笑>乐昌含笑.研究结果与大田容器苗受持续秋旱产生的旱害观测结果吻合,为苏南地区北移引种提供了科学依据.  相似文献   

13.
In this study, the effects of two different commercial neem insecticides (NeemAzal T/S and Neem Oil) were determined on different stages of Nezara viridula (L.) (Heteroptera: Pentatomidae) under laboratory conditions. Neem Azal and Neem Oil were applied at concentrations of 0.5 % and 2 %, respectively. Mortality was recorded after 3, 7 and 14 days for nymphs and adults; 7 and 14 days for old (4-day-old) eggs; and 14 days for newly laid (one-day-old) eggs. Both products have no significant effect on adults and newly laid eggs. However Neem Oil was found to be more effective than NeemAzal T/S on nymphs and on old laid eggs after 7 and 14 days. It can be concluded that both neem products have potential for insecticidal efficacy (approximately 60 %) against nymphs of N. viridula. at concentrations recommended by manufacturers for registered pests.  相似文献   

14.
Root-exudates of Neem/Margosa and Bakain/Persian lilac brought about considerable mortality ofHoplolaimus indicus, Helicotylenchus indicus, Tylenchus filiformis, Tylenchorhynchus brassicae, Rotylenchulus reniformis andMeloidogyne incognita, however, to varying extent. The root-exudate of Neem was more toxic to nematodes than that of Bakain. The root-exudates also inhibited larval hatch ofM. incognita.  相似文献   

15.
Laboratory evaluation of Neem Azal-S and Margosan-O was carried out against the adult and larvae ofLiriomyza trifolii Burgess. The feeding deterrent activity of both compounds was significantly realized against the adults particularly at high concentrations which lasted for 5 days after treatment. Both formulations also deterred the females from laying eggs and the percentage of oviposition deterrent index (ODI) reached 80.7 and 52.6 for Neem Azal-S and Margosan-O (2%), respectively.Post infestation treatment of bean seedlings containing 3rd instar larvae indicated that the toxic action of the tested extracts was quite limited. However, different percentages of malformed pupae were obtained. The sex ratio between the resulting adults was nearly unaffected with the exception of individuals whose larvae were treated with 2% Neem Azal-S where all the resulting progenies were females.With 2 tables  相似文献   

16.
云南省地方政府通过捕获信息、科学决策,制定印椿产业发展规划,引导印楝产业科学、合理、有序地发展。文章从3个方面阐述政府的有效组织是云南印椿产业快速发展的基础,即地方政府先期投入作为资金保障;科研先行。引进、筛选优良品种作为技术保障;集中育苗、加强幼苗管护作为管理机制保障。同时,抓住国家的政策机遇,强化印楝系列产品开发,开展国际合作,壮大印楝产业,使云南印楝种植规模迅速成为世界之最。  相似文献   

17.
Different concentrations of Neem Azal-T/S, an insect growth regulator (IGR) (antiecdysone) and various other insecticides were tested against the pistachio psyllid (Agonoscena targionii) affecting pistachio (Pistacia vera L.), in northern Syria. From 1997?–?99, three applications were made annually, in April, May, June or July. Results revealed that Neem Azal-T/S, at the rate of 0.5 and 0.7?%, Flufenoxuron, Teflubenzuron, and the antagonistic fungus Beauveria bassiana Bals. were highly effective against the psyllid especially on the 1st and 2nd nymph instars in the April application. The possibilities of using these pesticides in integrated management against pistachio psyllid in Syria are discussed.  相似文献   

18.
本文对印楝种籽的加工机理进行了研究,提出了满足生产需要的工艺路线,研制出了差速螺旋齿双级对滚破壳设备、吸风分离设备,获得了较好的加工效果。  相似文献   

19.
元谋干热河谷相思树种和桉树类抗旱能力分析   总被引:12,自引:1,他引:12       下载免费PDF全文
对元谋干热河谷引种的8种外来树种进行了抗旱性分析,发现水分利用效率从高到低的顺序依次是:窿缘桉、赤桉、柠檬桉、绢毛相思、肯氏相思、厚荚相思、大叶相思、马占相思。水分利用效率越高,对干热环境的适应性越强。8种外来树种适应干热河谷生境的旱性结构的特点是主根深、侧根多、栅栏组织和贮水组织发达、构成等面叶或近等面叶。桉树类树种的蒸腾速率较高,但能生存的主要机理根系分布深,主动供水能力强,补充了地上部分的水分消耗;而相思类则以发达的根系和较高的叶片保水能力来适应干热环境。  相似文献   

20.
The microstructural and ultrastructural traits of three kinds of typical leaves ofPopulus euphratica Olive, including lanceolate, broad-ovate and dentate broad-ovate leaves, were studied by using electron microscope and optical microscope. The resuits showed that with the leaves changing from lanceolate shape to dentate broad-ovate shape, their structure obviously tended to be xeromorph: developed palisade tissue, undeveloped spongy tissue, thick cutin layer and sunken stomas. The amount of mitochondria tended to be increased, and the shape of chloroplasts varied from regular spindle to irregular rotundity or oval. The leaves were covered with wax without cilium, and the stomas on the upper and lower epidermis of the leaves opened unevenly. The stomas on the lower epidermis were deeper than those on the upper epidermis under the scanning electron microscope. The results implied that the structural characteristics of the diversiform-leaves ofP euphratica are related to its eco-adaptability.  相似文献   

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