Fire sensitivity of broadleaf tree species in plantations of Kurdistan,Iran

To better manage wildfires and plantations in Kurdistan, native tree species commonly used in planting and reviving forests such as Quercus brantii Lindl., Q. infectoria Olivier, Q. libani Olivier, Pistachio atlantica Desf., Fraxinus rotundifolia Vahl, and Robinia pseudoacacia L. were evaluated and compared in terms of fire sensitivity and fire resistance. To determine fire sensitivity, indices such as the fl ammability index, ignition time, fl ame durability, moisture content, carbonized surface, mass reduction, bulk density, as well as dry weight of wood, bark, and leaves were used. The data were subjected to ANOVA. The means obtained, after examining homogeneity or heterogeneity of the variances, were compared using parametric and nonparametric comparison tests. There was a significant difference at the level of 5%. Based on the analysis of these indices, the species could be divided into three groups: species sensitive to fire such as Robinia pseudoacacia, species moderately sensitive to fire such as F. rotundifolia, and species relatively resistant to fire, including Q. brantii, Q. libani, Q. infectoria, and P. atlantica.     

杨梅树叶、皮、根部精油成分及其抗氧化活性物质

采用GC-MS技术结合Kovats保留指数(KI)对比法分析鉴定了采自南岭自然保护区的乌杨梅(Myrica rubravar.astropureaTsen.)叶、皮和根部芳香精油的成分,同时运用薄层层析(TLC)筛分法对其抗氧化活性物质进行了对比分析。杨梅树根和树皮精油的主要成分为5-羟基菖蒲烯(相对含量分别为74.66%和60.32%)和油酸(7.74%和11.39%),而树叶精油的主体成分为5-羟基菖蒲烯(30.44%)、石竹烯(11.61%)、异石竹烯(10.17%)、(E)-橙花叔醇(9.57%)和油酸(4.40%)。树根、树皮到树叶部位的次生代谢物明显出现越来越复杂的分化特性。5-羟基菖蒲烯是3个部位精油的主要抗氧化活性物质,但叶部精油中的倍半萜烯类物质也表现出一定的二苯代苦味酰(DPPH)自由基清除活性。     

Compositions and antimicrobial activities of the essential oils of two Hypericum species from Turkey

The chemical compositions of essential oils obtained from Hypericum hyssopifolium var. microcalycinum and Hypericum lysimachioides var. lysimachioides were analysed by using GC and GC-MS. Caryophyllene oxide was found to be the major component. The essential oils of both Hypericum species showed antimicrobial activity against nine microorganism at a concentration of 60 to 80 microg/ml.     

Factors influencing axillary shoot proliferation and adventitious budding in cedar

We developed procedures for in vitro cloning of Cedrus atlantica Manetti and C. libani A. Rich explants from juvenile and mature plants. Explant size was one determinant of the frequency of axillary bud break in both species. Shoot tips and nodal explants mainly developed calli, whereas bud sprouting occurred in defoliated microcuttings cultured on a modified Murashige and Skoog medium without growth regulators. Isolation and continuous subculture of sprouted buds on the same medium allowed cloning of microcuttings from C. atlantica and C. libani seedlings and bicentennial C. libani trees, thus providing a desirable alternative for multiplying mature trees that have demonstrated superior characteristics. We also report adventitious bud differentiation from isolated embryos of C. atlantica. Neither auxin treatments nor other methods tested, including infection with Agrobacterium rhizogenes, were effective in inducing root initiation.     

Chemical composition,antimicrobial and antioxidant activities of anethole-rich oil from leaves of selected varieties of fennel [Foeniculum vulgare Mill. ssp. vulgare var. azoricum (Mill.) Thell]

The chemical composition and biological activity of the essential oils obtained from the leaves of two different cultivars of Florence fennel cropped under three different fertilization treatments (Control not fertilized; Mineral Fertilization; Compost from Municipal Solid Wastes) have been analyzed. All the oils were characterized by high anethole concentration and some showed also a good percentage of limonene.Thus, the leaves of Florence fennel, which are agricultural wastes, could be used for the recovery of anethole to be used for its flavoring and biomedical properties. The antimicrobial activity expressed by assays on the examined oils indicates an appreciable effect, generally higher on Gram-positive bacteria. The various samples of Florence fennel analyzed did not show any results with FRAP test. The DPPH test showed a weak capacity of the samples to catch the free radicals from the solution, attributable to their content in anethole.     

春秋两季油樟叶的油细胞形态、精油成分及其抗氧化活性研究

首先利用组织透明法对春秋两季油樟叶中油细胞进行形态观察,统计油细胞密度和直径,利用扫描电镜(SEM)进一步观察油细胞的细胞壁结构;其次对春秋两季油樟叶进行油樟精油的提取,利用GC-MS鉴定油樟精油的化学成分,利用GC分析了1,8-桉叶素、α-松油醇和γ-松油烯3种主要成分的含量;最后对油樟精油的抗氧化活性进行检测。研究结果表明:春季和秋季油樟叶片的油细胞密度分别为(41±3)和(38±2)个/mm²,油细胞直径分别为(51.87±1.64)和(36.89±2.64)μm,细胞壁厚度分别为1.65和0.63μm;春季和秋季油樟叶的精油提取得率分别为4.45%和3.09%(以干质量计),GC-MS表征鉴定出16个化合物,3种主成分的含量没有显著性差异;春秋两季的油樟精油总抗氧化能力分别为6.50和5.50 U/mL,达到Vc的40%,清除DPPH自由基的半数抑制质量浓度(IC₅₀)均为0.2 g/L。     

Compositions and antifungal activities of essential oils of some Algerian aromatic plants

Essential oils extracted from ten Algerian plants were analyzed for their potential activity against Candida albicans. The highest efficiency was obtained with the essential oil from Thymus numidicus which showed antifungal effect 1357 fold stronger than that measured with amphotericin B.     

Site-related influences on cone-borne inoculum and asymptomatic persistence of Diplodia shoot blight fungi on or in mature red pines

The shoot blight and canker pathogens Diplodia pinea and D. scrobiculata sporulate abundantly on cones of many pine hosts. Variation in incidence and abundance of potential inoculum from cones and frequency of asymptomatic persistence on or in shoots was examined for mature red pines in sites differing in dominant presettlement vegetation and soil type in Bayfield and Douglas counties in northern Wisconsin. Collections were made in each county from 6 plantations, 3 each in areas historically vegetated with jack pine and soils mapped as sands and three in areas historically vegetated with red pine with soils mapped as loamy sands. At each site, 5 cones were collected from each of 5 red pines and 10 shoots were collected from up to 5 red pines. Conidia from cones were quantified with a water wash and filtration technique. Diplodia species were cultured from surface-disinfested asymptomatic shoots. A species-specific PCR assay was used to identify the Diplodia species from cones and shoots. Although cones and asymptomatic shoots from each county yielded D. pinea and D. scrobiculata, D. pinea was detected more frequently. More conidia were obtained from cones from Douglas Co., where there is a history of severe shoot blight damage, than cones from Bayfield Co. In Douglas Co., more conidia were obtained from cones from plantations in areas of more sandy soil and presettlement jack pine dominance than cones from plantations in areas of less sandy soil and presettlement red pine dominance. The numbers of conidia and frequencies of cultural detection of Diplodia species from asymptomatic shoots at a site were positively correlated. These results provide evidence for site-related influences on abundance of pathogen inoculum and asymptomatic persistence on or in red pine crowns that may contribute to differences in frequency and severity of damage from Diplodia shoot blight.     

Variability in growth, carbon isotope composition, leaf gas exchange and hydraulic traits in the eastern Mediterranean cedars Cedrus libani and C. brevifolia

Four Turkish provenances and five Lebanese provenances of Cedrus libani A. Rich. and one Cypriot provenance of C. brevifolia Henry were compared during the third year of growth in a controlled-climate greenhouse after exposure to a well-watered or moderate-drought treatment. Effects of treatment on CO(2) assimilation (A), stomatal conductance (g(s)), (13)C isotope composition (delta(13)C), growth and biomass were assessed. Hydraulic conductivity and shoot vulnerability to cavitation were measured in well-watered plants only. The Lebanese provenances of C. libani had the highest growth rates, but were the most sensitive to drought. The Turkish provenances of C. libani showed moderate growth rates and moderate drought sensitivity. Cedrus brevifolia had the lowest growth rate and was least sensitive to drought. For each provenance, mean biomass values were positively correlated with delta(13)C and intrinsic water-use efficiency (A/g(s)), and negatively correlated with g(s). Drought reduced growth and favored carbon storage in roots, increasing the ratio of root biomass to aboveground biomass. The drought treatment increased delta(13)C and A/g(s). Specific hydraulic conductivity (K(s)) was similar for the provenance groups, whereas leaf-specific conductivity (K(l)) was lower in the Lebanese provenances than in the other provenances. Within each provenance group, provenances with the highest K(l) were most susceptible to xylem cavitation, but were also the most productive. Growth and drought adaptation were linked with precipitation in each provenance's native range.     

云南产白兰花和叶挥发油的化学成分研究

用水蒸气蒸馏法提取了春季产白兰叶(LM-1)和夏季产白兰花(FM)和叶(LM-2)的挥发油,采用气相色谱-质谱联用技术并结合计算机检索对其挥发油的香气成分进行了分析.分别从春季产白兰叶、夏季产白兰花和叶的挥发油中鉴定出了74、80及88个成分.用面积归一法测定了3种挥发油中各种成分的GC含量,各占总峰面积的96.8%、97.7%和98.9%.白兰花油和叶油的主要成分基本相同,它们分别是芳樟醇、α -小茴香烯、丁香油酚甲醚、反式罗勒烯、2,4-二异丙烯基-1-甲基-1-乙烯基环己烷、石竹烯、大根叶烯 D、异丁香油酚甲醚、橙花叔醇、α -葎草烯、桉叶油素等.     

Drought effects on hydraulic conductivity and xylem vulnerability to embolism in diverse species and provenances of Mediterranean cedars

We studied hydraulic traits of young plants of the Mediterranean cedar species Cedrus atlantica (Endl.) G. Manetti ex Carrière (Luberon, France), C. brevifolia (Hook. f.) Henry (Cyprus), C. libani A. Rich (Hadeth El Jebbe, Lebanon) and C. libani (Armut Alani, Turkey). With an optimum water supply, no major differences were observed among species or provenances in either stem hydraulic conductivity (Ks) or leaf specific conductivity (Kl) measured on the main shoot. A moderate soil drought applied for 10 weeks induced marked acclimation through a reduction in Ks, particularly in the Lebanese provenance of C. libani, and a decrease in tracheid lumen size in all species. Cedrus atlantica, which had the smallest tracheids, was the species most vulnerable to embolism: a 50% loss in hydraulic conductivity (PsiPLC50) occurred at a water potential of -4.4 MPa in the well-watered treatment, and at -6.0 MPa in the moderate drought treatment. In the other species, PsiPLC50 was unaffected by moderate soil drought, and only declined sharply at water potentials between -6.4 and -7.5 MPa in both irrigation treatments. During severe drought, Ks of twigs and stomatal conductance (g(s)) were measured simultaneously as leaf water potential declined. For all species, lower vulnerability to embolism based on loss of Ks was recorded on current-year twigs. The threshold for stomatal closure (10% of maximum g(s)) was reached at a predawn water potential (Psi(pd)) of -2.5 MPa in C. atlantica (Luberon) and at -3.1 MPa in C. libani (Lebanon), whereas the other provenance and species had intermediate Psi(pd) values. Cedrus brevifolia, with a Psi(pd) (-3.0 MPa) close to that of C. libani (Lebanon), had the highest stomatal conductance of the study species. The importance of a margin of safety between water potential causing stomatal closure and that causing xylem embolism induction is discussed.     

Evaluation of antimicrobial activity of Cleome viscosa and Gmelina asiatica

The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi.     

龙脑樟叶部精油在不同蒸馏时段的出油率和化学成分

考察龙脑樟叶在不同蒸馏时段的出油率和化学成分。采用水蒸汽蒸馏的方法、水中蒸馏的方式,将2 h的蒸馏过程分成4个阶段,收集相应的馏分,分别进行计量和GC-MS分析,结果表明,总出油率达到2.81%,蒸馏一开始就产生大量的馏分,96.53%的馏分集中在前60 min内蒸出。通过GC-MS分析鉴定,发现龙脑樟叶挥发油中主成分为右旋龙脑（天然冰片）,其含量高达81.78%,其余还有樟脑、1,8-桉叶油素、黄樟油素、α-蒎烯、芳樟醇、乙酸龙脑酯等31个化学成分。     

Insect growth regulatory activity of Vitex trifolia and Vitex agnus-castus essential oils against Spilosoma obliqua

Essential oils of Vitex trifolia and Vitex agnus-castus were evaluated against Vth instar larvae of Spilosoma obliqua, when applied topically on the dorsal side of mesothoracic region, for insect growth regulatory activity. This treatment caused extended larval period and pupal period, increase in larval mortality and adult deformity and decrease in adult emergence, fecundity of female and egg fertility of test insect.     

Composition and antitermite activities of essential oils from <Emphasis Type="Italic">Melaleuca</Emphasis> species

 The composition and antitermite activities of nine essential oils from two Melaleuca species, gelam and cajuputi, were compared using gas chromatography–mass spectrometry analysis and bioassays. Gelam oils were rich in compounds whose boiling points were high, and they were separated into the elemene-rich type and the γ-terpinene- and terpinolene-rich type. Cajuputi oils in this experiment were categorized into three chemotypes according to their 1,8-cineole content: high, low, none. In the termiticidal activity test, gelam oils were stronger than most cajuputi oils in the contact condition. The elemene-rich gelam lost its activity in the noncontact condition, whereas another type of gelam kept its termiticidal activity. The authentic sample of elemene showed the same result as the elemene-rich gelam, indicating that the termiticidal activity of gelam was caused by at least two types of compound: elemene and “others.” 1,8-Cineole exhibited the same tendency as elemene, but it was weak. Hence the 1,8-cineole content of cajuputi was irrelevant to termiticidal activity of samples that exhibited strong activity under both conditions despite their high content. The appearances of gelam and cajuputi leaves are easily confused, a problem that has not yet been solved. Other scientific methods, such as genetic analysis, are required to identify gelam. The difference in the compositions and antitermite activities, however, were charified in this experiment. Received: November 30, 2001 / Accepted: June 5, 2002 Correspondence to:M. Yatagai     

竹叶挥发油化学成分及其抗氧化特性

采用水蒸气蒸馏法从黄金间碧竹、孝顺竹、毛竹和麻竹4种竹叶中提取挥发油,用气相色谱-质谱联用技术对4种竹叶挥发油化学成分进行分析和鉴定,共获得168个色谱峰,鉴定其中132种化学成分,并运用气相色谱面积归一化法确定各组分的相对含量;以TBHQ为对照品,采用DPPH法研究4种竹叶挥发油对自由基的清除作用.结果表明:采用水蒸气蒸馏法黄金间碧竹竹叶挥发油的得率最高(0.827%),而毛竹竹叶挥发油的得率仅为0.391%.4种竹叶挥发油的化学成分在含量和组成上不同,竹叶挥发油主要化学成分是3-甲基-2-丁醇,麻竹竹叶挥发油含量最高达到46.25%;其他主要化学成分有4-乙烯基-2-甲氧基-苯酚、己-2-烯醛、橙花叔醇、植物醇、苯乙醛、天竺葵醛、植酮、二氢猕猴桃内酯和异植物醇.4种竹叶挥发油均有较强的抗氧化活性,竹叶挥发油的抗氧化活性与挥发油的浓度呈正相关(r=0.91),其中黄金间碧竹竹叶挥发油的抗氧化活性最强(IC50=2.705mg·mL-1),孝顺竹竹叶挥发油抗氧化活性较低(IC50=3.442mg·mL-1).综合研究结果表明,竹叶挥发油具有较高的应用价值,可作为食品和药品的功能性组分进一步开发和利用.     

Repellent activity of selected essential oils against Aedes aegypti

Essential oils extracted from ten plant species were screened for repellency against Aedes aegypti mosquitoes. Three oils; Zanthoxylum piperitum, Anethum graveolens and Kaempferia galanga, exerted protection against A. aegypti, with median complete-protection times of 1, 0.5 and 0.25 h, respectively. The protection times were increased significantly by incorporating 10% vanillin. The highest potential was established from Z. piperitum oil +10% vanillin (2.5 h, range=1-2.5 h). Mixtures from pairs of the effective oils possessed slight repellency that ranged from 0-0.5 h. None of the oil combinations repelled A. aegypti for longer than their constituent oil alone. With vanillin added, however, each oil mixture provided improved protection, which was approximately equal to oil on its own. GC/MS analysis revealed that the main component of Z. piperitum fruit oil was limonene (37.99%), with minor amounts of sabinene (13.30%) and beta-myrcene (7.17%). Repellent testing of stored samples of Z. piperitum fruit oil against A. aegypti demonstrated that repellent activity of those kept at -20 degrees C or 4 degrees C was present for a period of at least 3 months. Therefore, the essential oil of Z. piperitum fruit may prove useful in the development of mosquito repellents as an effective personal protection measure against mosquito bites.     

2种一枝黄花叶的挥发油化学成分和抑菌活性

我国野生的一枝黄花(Solidago decurens)为菊科一枝黄花叶属植物,生长于阔叶林缘、林下、灌丛中及山坡草地上,其全草是一种传统中药(中国植物志编辑委员会,1985;徐国钧,1997),但其挥发油成分未见研究报道.同时,加拿大一枝黄花(S.canadensis)也为菊科一枝黄花叶属植物,适应力强,是近年来在我国扩散较严重且难以有效控制的入侵有害植物.     

Chemical composition and antifungal properties of essential oils of three Pistacia species

The chemical composition of essential oils obtained from the leaves of Pistacia vera, Pistacia terebinthus, Pistacia lentiscus and the resin of Pistacia lentiscus were analyzed by GC and GC-MS. alpha-Pinene, beta-pinene, limonene, terpinen-4-ol and alpha-terpineol were found to be the major components. The antifungal activities of the above oils and P. lentiscus resin (total, acidic and neutral fractions) against the growth of three agricultural pathogens, Pythium ultimum, Rhizoctonia solani and Fusarium sambucinum were evaluated. Some doses of P. terebinthus, P. vera and P. lentiscus leaf oils and total and neutral fraction of P. lentiscus resin significantly inhibited the growth of R. solani. However, all samples did not show antifungal activity against P. ultimum and F. sambucinum, but increased the growth of F. sambucinum.