桉叶挥发物变化及桉树枝瘿姬小蜂趋性反应

采用GC-MS和四臂嗅觉仪测定了桉树DH32-28、DH201-2、GL-UG9无性系健康树叶和经桉树枝瘿姬小蜂诱导桉叶挥发物的变化,及其对枝瘿姬小蜂成虫的诱集作用。结果表明,诱导的和健康的桉叶挥发物提取率由高到低依次为DH32-28、DH201-2、GL-UG9无性系,同一无性系诱导的桉叶提取率较健康的低;经诱导的桉叶挥发物萜类和醇类物质种类较健康桉叶的多,绿叶类、醛和酮类、芳香类化合物也较多;在四臂嗅觉仪的终选区,健康的DH201-2和GL-UG9桉叶对桉树枝瘿姬小蜂成虫具有明显的诱集作用,而健康的DH32-28桉叶未表现出明显的诱集作用,经诱导的DH201-2、GL-UG9和DH32-28桉叶挥发物则表现出明显的诱集作用。

梨树挥发物成分的鉴定及其对梨叶斑蛾的触角电位反应

[目的]筛选梨叶斑蛾引诱物质。[方法]利用气相色谱-质谱联用仪(GC-MS)分析了梨树挥发物的主成分,并通过触角电位仪(EAG)测定了梨叶斑蛾对主要挥发物的电生理反应。[结果]梨叶中共鉴定出包含萜类、酯类、醛类及醇类在内的24种主要挥发物。梨叶斑蛾雌雄蛾对供试挥发物均可产生EAG反应,其中雌蛾对芳樟醇、月桂烯、反-β-罗勒烯的反应最明显;雄蛾对芳樟醇、反-β-罗勒烯、α-法尼烯的反应最强烈。剂量反应试验结果表明,梨叶斑蛾雌蛾对3种供试化合物的EAG活性与化合物的剂量之间呈正相关性。[结论]试验结果为制定基于植物源的梨叶斑蛾监测与防治策略提供了理论依据。

扬州古运河沿岸生态林主要绿化树种抑菌功能的初步研究

The paper reported antimicrobial function of different trees species in woodland along the Grand Canal, Yangzhou, China, at 16:30-17:00, Sep 5, 2004. The tested result showed that in different communities of Platycladus orientalis,Osmanthus fragrans, Cedrus deodara, Albizzia julibrissin, Cinnamomum camphora had antibacterial action. The content of pollutant bacteria in the forest atmosphere (1.5～1.8 m above the land) decreased obviously,which amounted to 23.59%～99.78% compared with the control in open area and 10.08%～99.71% compared with the near communities away from {15 m} distance. There was nat antifungal (against mold) effect in general; only two tree communities for Osmanthus fragrans (decreased 40.66% compared with the near 15 m distance) and P.orientalis (decreased 24.73% than in open area) had less antifungal effect. At the same time, the antimicrobial activities were tested by the extractive volatile of foliage for more tree species in lab. The results showed that antibacterial activities to against Staphalococus aureus and Escherichia coli were the highest in P.orientalis , Manglietia yuyuanensis and C.camphora , and higher in Koelreuteria bipinnata, Viburnum macrocephalum, Metasequoia glyptostroboides, Eriobotrya japonica, Ginkgo biloba, C.deodara, Magnolia grandiflora, Sabina chinensis. Most of the tree species tested had less antifungal activities against Fusarium graminerum and Glomerella cingulata. While Ginkgo biloba, Cinnamomum camphora, S.chinensis, Elaeocarpus sylvestris and C.deodara had higher antifungal activities against G.cingulata than others. The P.orientalis, C.camphora, S.chinensis Magnolia grandiflor, G.biloba, Acer mono, Acer palmatum had higher antifungal activities against F.graminerum than others.The research results recognized that the suitable cultivated tree species in cities were P.orientalis, C.deodara, C.camphora and M.glyptostroboides.

Leaf Volatiles from Host Tree Acer negundo : Diurnal Rhythm and Behavior Responses of Anoplophora glabripennis to Volatiles in Field

The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, etc. were identified. The analysis revealed that the diurnal rhythm of release of volatile compounds from maple differed in July and in August. In July, the releasing of most volatile compounds reached the peak at 14 o'clock, when in August, the emission of volatile compounds reached the peak at 10 o'clock. Besides diurnal rhythm, there also existed other differences in the releasing of volatiles and their relative contents in July and in August. A possible explanation for this phenomenon is the maturation of leaves, since the sampling conditions were the same both in July and August. At the same time, the response of Anoplophora glabrpennis Motschulsky to volatiles was examined with field bioassay with traps. cis-3-hexen-1-ol was found to be more effective to attract A. glabrpennis than other volatiles released by ash-leaf maple tree in field trapping test. A mixture of 1-butanol, 1-pentanol and 2-pentanol was tested to be the most attractive to A. glabripennis among all tested volatiles. More field trapping tests should be conducted.

Changes in sulfur form during coal desulfurization with microwave:Effect on coal properties

The changes in sulfur form in coal were analyzed by sulfur K-XANES(K-edge X-ray absorption near edge structures) spectra before and after the coal microwave desulfurization in a Na OH solution. After the desulfurization, the pyritic sulfur content of coal decreased significantly from 53.6% to 39.2%, while the sulfate sulfur content increased from 17.3% to 34.6%. Only a small amount of thiophene sulfur(20.1–16.1%) was removed. Some sulfur-containing components were oxidized to sulfate sulfur. Under the optimum conditions, the ash content decreased, while the volatile content increased. The calorific value of coal slightly decreased with a slight variation in the amplitudes. The overall structure of coal did not change significantly based on Fourier transform infrared(FTIR) spectral analyses. Thus, the desulfurization of coal with microwave irradiation in a Na OH solution did not significantly change the properties of coal.

An oriental melon 9-lipoxygenase gene CmLOX09 response to stresses, hormones, and signal substances

In plants, lipoxygenases （LOXs） play a crucial role in biotic and abiotic stresses. In our previous study, five 13-LOX genes of oriental melon were regulated by abiotic stress but it is unclear whether the 9-LOX is involved in biotic and abiotic stresses. The promoter analysis revealed that CmLOX09 （type of 9-LOX） has hormone elements, signal substances, and stress elements. We analyzed the expression of CmLOX09 and its downstream genes--CmHPL and CmAOS-in the leaves of four-leaf stage seedlings of the oriental melon cultivar ＂Yumeiren＂ under wound, hormone, and signal substances. CmLOX09, CmHPL, and CmAOS were all induced by wounding. CmLOX09 was induced by auxin （indole acetic acid, IAA） and gibberellins （GA3）; however, CrnHPL and CmAOS showed differential responses to IAA and GA3. CmLOX09, CmHPL, and CmAOS were all induced by hydrogen peroxide （H2O2） and methyl jasmonate （MeJA）, while being inhibited by abscisic acid （ABA） and salicylic acid （SA）. CmLOX09, CmHPL, and CmAOS were all induced by the powdery mildew pathogen Podosphaera xanthii. The content of 2-hexynol and 2-hexenal in leaves after MeJA treatment was significantly higher than that in the control. After infection with P. xanthii, the diseased leaves of the oriental melon were divided into four levels-levels 1,2, 3, and 4. The content of jasmonic acid （JA） in the leaves of levels 1 and 3 was significantly higher than that in the level 0 leaves. In summary, the results suggested that CmLOX09 might play a positive role in the response to MeJA through the hydroperoxide lyase （HPL） pathway to produce C6 alcohols and aldehydes, and in the response to P. xanthiithrough the allene oxide synthase （AOS） pathway to form JA.