米槁-绿壳砂林药间作系统可行性

为了充分利用米槁林下空间,从化感效应的角度研究人工米槁林下土壤水浸提液对绿壳砂生长状况的影响,探索米槁与绿壳砂建立间作经营系统的可能性。以绿壳砂为受体,米槁根际土壤与林间土壤水浸提液为供试液,设置6个浓度0、0.5、1、5、10、50 mg/mL的水浸提液处理绿壳砂,对绿壳砂种子萌发和幼苗生理生化指标进行测定,以此探讨米槁根际土壤与林间土壤水浸提液对绿壳砂生长的影响。结果表明:米槁两种土壤水浸提液对绿壳砂种子的萌发大体上呈现低浓度促进高浓度抑制的浓度效应,但随着浓度的变化,差异不显著;米槁林间土壤水浸提液对绿壳砂幼苗的总生物量及苗高都表现出显著的促进作用,呈先增加后缓慢减小的趋势,根际土壤水浸提液则在高浓度时表现出抑制作用。从化感效应综合指数看出,2种水浸提液对可溶性蛋白质含量、游离脯氨酸(Pro)含量、土壤脲酶(S-UE)活性表现为抑制作用,其余都为促进作用,且林间土壤的促进效果强于根际土壤。应用GC-MS从米槁根际土壤与林间土壤中分别鉴定出18种化合物,虽含有酚酸和烷烃类等化感物质,但在一定浓度范围内,对绿壳砂种子萌发、幼苗生长没有明显的抑制作用,且在米槁林土水浸提液处理下表现出更强的适应性。因此,在米槁林下套种绿壳砂时采取幼苗移栽法,构建米槁-绿壳砂林药间作经营体系具有一定可行性。     

湖南油樟的化学类型

对湖南省的油樟（Cinnamomum longepaniculatum (Gamble)N.Cho ex H.W.Li）资源作了调查。用色谱、色谱/质谱联用方法鉴定了油樟叶精油的43个化学成分,依主含成分不同可将其划分为6个不同的化学类型。其中,主含甲基丁香酚、龙脑、樟脑、芳樟醇和倍半萜烯的5个化学类型为首次在油樟中发现。     

樟树新害虫——窃达刺蛾的研究

窃达刺蛾是樟树新害虫,在福建一年发生3代,以幼虫在叶背越冬。翌年3月上旬化蛹,4月上旬成虫出现并产卵,4月中旬幼虫孵出,5月中旬陆续化蛹．6月上旬成虫羽化,6月中旬第二代幼虫开始出现,8月下旬第三代幼虫出现。在幼虫三龄前,喷洒5％辛硫磷,40％氯化乐果乳剂或80%敌敌畏乳剂1000倍液,均可收到良好效果。     

樟树核糖体失活蛋白在种子成熟过程中的动态变化与特性

樟树种子中存在着ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ两种新的核糖体失活蛋白,电泳分析与Ｗｅｓｔｅｒｎ杂交结果表明ｃｉｎｎａｍｏｍｉｎ在９、１０、１１月份种子中的含量分别是８．９％,２６．８％和１１．５％,以１０月份种子的含量为最高。ｃａｍｐｈｏｒｉｎ的含量则分别为１．７％,２．５％与４．６％,随着种子的成熟而不断增加。８月份的幼嫩种子中检测不出ｃｉｎｎｍａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ．这表明樟树核糖体失活蛋白的表达受到了发育进程的时态调控．樟树叶片中可能不存在ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ,即两者的合成似乎具有一定的组织特异性．ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ均为糖蛋白。     

樟精油成分和类型划分

用色谱、色谱-质谱联用、红外光谱和其他化学方法鉴定了樟精油中的34个成分。通过164株樟不同部位的363个精油样品的分析,观察到不同树龄的植株及不同部位精油成分的差异。叶部精油具有显著的特征。按照叶油的主成分可将樟划分为五个化学类型(生理类型):樟脑型、芳樟醇型、桉油素型、龙脑型和异橙花叔醇型。     

Interstrains comparison of the antimicrobial effect and mode of action of a Vietnamese Cinnamomum cassia essential oil from leaves and its principal component against Listeria monocytogenes

The antibacterial activity of a Cinnamomum cassia essential oil (EO) and of its main component trans-cinnamaldehyde (90% w/w) was examined against five Listeria monocytogenes strains. The minimal inhibitory concentrations (MICs) of C. cassia EO against the five L. monocytogenes strains were identical (250 µg ml⁻¹), while the minimal bactericidal concentrations (MBCs) ranged between 800 and 1200 µg ml⁻¹. In order to study if this EO and trans-cinnamaldehyde altered the five strains at the membrane level, fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene (DPH) was measured in presence of different concentrations (1/2MIC, MIC, 2MIC) of these antibacterial agents. A concentration-dependent increase of fluorescence anisotropy of DPH in their presence reflecting a rigidification of the membrane was observed for the five strains. This modification of the membrane fluidity was associated with a perturbation of the selective membrane permeability, as a perturbation of the gradient between intracellular and extracellular pH was also observed.     

Developmental mechanism and distribution pattern of stomatal clusters in Cinnamomum camphora

We report the stomatal cluster development mechanism and distribution pattern in Cinnamomum camphora. The results indicated that the clustered arrangement of meristemoids at the juvenile stage of the leaf development contributed greatly to the pattern of stomatal clusters. Additionally, division of an epidermal cell (EC), which is between small stomata, and growth of small stomata to push the ECs aside to become directly contacting had an impact on the development as well as the pattern of stomatal clusters. The latter way may play a more important role in stomata clustering of the wide-type C. camphora. There are no significant difference in the stomatal index (the number of stomata per the sum of the number of epidermal cells and the number of stomata) among different part of leaves, while the stomatal cluster index (the number of stomata in stomatal clusters per the total number of stomata) was found to increase gradually from the apex to the base and from the middle part to the marginal part of the leaf. The possible reason of this pattern was discussed. Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 3, pp. 348–353. The text was submitted by the authors in English.     

天竺桂挥发油化学成分及抑菌活性研究

用水蒸馏法提取天竺桂(CinnamomumjaponicumSibe)挥发油,并用GC-MS分析化学成分,用滤纸片法测其抑菌活性。结果表明,从天竺桂挥发油中分离出27种化学成分,以冰片为主要成分,占26.03%;抑菌实验中,挥发油对大肠杆菌、枯草杆菌和金黄色葡萄球菌都有明显的抑菌作用。