黑盾胡蜂触角感受器的扫描电镜观察

为明确黑盾胡蜂(Vespa bicolor)触角及感受器的外部形态特点,利用扫描电镜对黑盾胡蜂雄蜂和工蜂触角感器的形态特征、类型和分布特点等超显微结构进行观察。结果显示,黑盾胡蜂触角呈膝状,由柄节、梗节和鞭节组成,其中雄蜂的鞭节有11小节、工蜂的鞭节有10小节。黑盾胡蜂共有5种触角感器,分别为毛形感受器(TS Ⅰ、TS Ⅱ)、板形感受器(PS Ⅰ、PS Ⅱ)、刺形感受器(CS Ⅰ、CS Ⅱ)、锥形感受器(BS Ⅰ、BS Ⅱ)、腔锥形感受器CoS,其中以毛形感器和板形感器数量最多、分布范围最广。黑盾胡蜂雄蜂和工蜂具有相同的感器类型和形态,仅感器大小和分布位置略有差异。     

不同品种茶花在干旱胁迫下叶 片气孔和蜡质的差异化表现

摘要：以茶花品种?十八学士''和?情人节''为研究对象，在塑料大棚室温15～25℃下，采用盆栽控水法进行干旱胁迫，利用扫描电子显微镜观测叶片的表皮结构。研究不同品种在干旱胁迫下，叶片表皮结构的差异对抗旱性的影响，为茶花的栽植管护推广和造景应用提供基础性的理论依据。 结果表明，茶花叶片仅有下表皮具有气孔，上、下表皮都有不同程度量的蜡质附着物。随干旱胁迫程度的加重，气孔开合及蜡质积累出现差异性变化。抗旱性较差的品种，主要通过利用蜡质的合成、堆积来堵塞气孔，降低蒸腾作用。抗旱性较强的品种，气孔的保卫细胞在干旱早期就启动闭合响应机制，叶片上表面的蜡质堆积程度更强，能更好的保护叶片免受光照和有害物质的伤害，说明叶片表皮结构对于茶花抗旱性强弱的决定作用较大。     

Feasibility study on the estimation of the living vegetation volume of individual street trees using terrestrial laser scanning

As an important part of urban greening, the canopy of street trees has ecological benefits, such as oxygen production, noise reduction, and dust reduction. The living vegetation volume (LVV) can reflect the spatial structure of the canopy intuitively and enables the estimation of the ecological service value of street trees. Terrestrial laser scanning (TLS) has shown excellent performance for providing three-dimensional data of individual trees with high precision, enabling the accurate quantification of the LVV. In this study, we divided the LVV into the total living vegetation volume (tLVV) and the effective living vegetation volume (eLVV); the latter does not include branches. The eLVV of 40 ginkgo trees separated in two roads in Nanjing was calculated from TLS data. A novel method named LAIM for accurate eLVV calculation based on point cloud data was proposed. The point cloud data of individual tree was segmented along the Z-axis and image processing methods were used. With this, eLVV of each tree was obtained. The results were compared with data obtained from a clustered point cloud generated using convex hulls. The Bland-Altman analysis was used to investigate the consistency of the two methods. Furthermore, we used correlation analysis and all-subsets regression to choose the variables, and the eLVV was fitted using six models. Finally, we evaluated O₂ production, CO₂ and SO₂ absorption by the street trees based on eLVV, the ecological benefits of street trees were quantified. The results showed the following: (1) The number of layers and the dilation size of the point cloud were crucial parameters in the LAIM. (2) For ginkgo trees, the mean difference between the eLVV obtained from the LAIM and the convex hull method was − 0.53–0.19 m³, indicating that the results were highly consistent for the two methods. (3) The eLVV fitting performance was better for the exponential function model (R² =0.8523, RMSE=0.6838 m³) and linear model (R² =0.8361, RMSE=0.7224 m³). The tree height and crown width significantly affected the eLVV estimation. (4) The evaluation about ecological benefits of Zhaoyang Road was better than Cuizhu Road. The quantified ecological benefits were conducive to road ecological evaluation. This study quantified the eLVV of individual trees using TLS, highlighting the importance of live vegetation in urban greening. The results can provide technical support for estimating the ecological service value of urban street trees.     

美国白蛾触角感器的超微结构

为明确美国白蛾Hyphantria cunea成虫触角上感器的种类、形态和分布，通过扫描电镜观察美国白蛾雌、雄成虫触角上感器的超微结构。结果显示，美国白蛾雌成虫触角呈锯齿状，雄成虫触角呈双栉节状。雌、雄成虫触角上的感器类型有所不同，个别感器的长度和基部直径差异显著。美国白蛾成虫触角上分布9类共16种感器，即4种毛形感器Ⅰ～Ⅳ、2种刺形感器Ⅰ～Ⅱ、1种鳞形感器、2种锥形感器Ⅰ～Ⅱ、2种腔锥形感器Ⅰ～Ⅱ、1种栓锥形感器、1种舌形感器、2种Bǒhm氏鬃毛Ⅰ～Ⅱ以及1种新的感器——单孔栓感器。毛形感器数量最多，且雄成虫触角上的毛形感器数量多于雌成虫触角上的。单孔栓感器数量较少，雌、雄成虫触角上仅发现2～3个，在雌成虫第1～3鞭亚节腹面锯齿端部各分布有1个。毛形感器Ⅳ——超长毛形感器及舌形感器仅分布在雄成虫触角上。锥形感器Ⅰ～Ⅱ、腔锥形感器Ⅰ和Bǒhm氏鬃毛Ⅰ～Ⅱ的长度在雌、雄成虫间均差异不显著，而其余感器的长度在雌、雄成虫间均差异显著；雄成虫触角上毛形感器Ⅰ～Ⅲ、腔锥形感器Ⅱ和刺形感器Ⅰ～Ⅱ的长度均显著大于雌成虫触角上的，雌成虫触角上鳞形感器和栓锥形感器的长度显著大于雄成虫触角上的。表明美国白...     

生物炭添加对盐渍土CT孔隙序列分形特征来源的影响

为了揭示生物炭改良土壤孔隙的复杂结构及其影响因素，以江苏滨海盐渍土为研究对象，采用添加生物炭改良盐渍土，设置0,2%,5%(占表层0—20 cm土重比)3个生物炭添加水平。每年10月在水稻收割后，采用塑料环刀取表层(0—20 cm)原状土，进行Micro-CT扫描获取土壤CT孔隙序列。基于多重分形去趋势波动分析理论，并结合数据重排，分析施加生物炭对CT孔隙序列多重分形特征及其来源的影响。结果表明，所有处理的CT孔隙序列的复杂度均随着年份增长；2%生物炭处理的CT孔隙序列的复杂程度较0和5%生物炭处理分别提高7.54%和5.28%;概率密度函数与长程相关性均影响CT孔隙序列的多重分形特征；孔隙和空间的长程相关性是主要影响因素；生物炭的添加促使孔隙分形特征更易受到土壤中生物微生物活动的影响。研究结果为定量化分析生物炭改良盐渍土孔隙结构提供了理论支持。     

山桃组培苗无糖生根培养研究

针对桃组培苗生根率低，侧根少，质地脆，移栽成活率低的情况，研究采用无糖生根技术，以山桃(Prunus davidiana)组培苗为实验材料，探讨了生长素、蛭石含水量对山桃根系发育的影响，并观察了不同时期山桃根系和地上部的生长发育情况。结果表明：(1)生长素为1.0 mg/L IBA时，山桃生根情况最好。(2)适宜山桃无糖生根的蛭石含水量为65%～70%。(3)山桃组培苗培养到第10天可以观察到明显的根尖，第25天时生根率达到100%,第35天时最适合移栽。无糖生根能明显改善山桃组培苗的生根情况，生根率和平均生根数显著提高，苗子生长健壮，根系发达，操作简单，适宜在生产中推广使用。     

施加生物质炭对盐渍土土壤结构和水力特性的影响

以江苏省沿海围垦区盐渍土为研究对象,基于Micro-CT图像扫描技术,分析施加生物质炭后改良盐渍土土壤孔隙度、土壤水分特征曲线以及非饱和导水率等土壤特性的变化,并建立分形模型预测土壤水力性质,以此揭示施用生物质炭对于海涂围垦区盐渍土土壤结构和水力特性的影响。试验设置0、2%、5%(与表层0～20 cm土壤质量比) 3个生物质炭添加水平,重复3次。结果表明:施加5%生物质炭显著降低盐渍土土壤容重,增加土壤总孔隙度和大孔隙度;大于0. 25 mm水稳性团聚体质量分数显著增加,增加土壤孔隙分形维数;提高土壤饱和含水率和饱和导水率;结合Micro-CT图像扫描技术和孔隙分形理论预测改良盐渍土土壤水分特征曲线和非饱和导水率,预测效果精度高,能够用于实际问题的研究。     

Screening,identification, and observation of infection process of a herbicidal fungal strain HY-02

This study clarified the herbicidal activity, crop safety, classification status, and infection process of herbicidal strain HY-02, and laid a foundation for its development and utilization. Strain HY-02 was isolated from the leaves of Rumex patientia L. by the tissue isolation method. The pathogenicity of the strain to six broadleaf weeds and the safety for four common crops were determined by spray inoculation. The taxonomic status of HY-02 was determined by morphology and molecular biology, and the infection process was confirmed by scanning electron microscopy. In vitro leaf experiments showed that strain HY-02 was pathogenic to six broadleaf weeds, Polygonum aviculare L., Elsholtzia densa Benth., Chenopodium album L., Polygonum lapathifolium L., Amaranthus retroflexus L., and Malva verticillata L. The pot experiment of weeds found that the pathogenicity rates for P. aviculare, E. densa, C. album, P. lapathifolium, A. retroflexus, and M. verticillata were 100.00%, 94.44%, 95.24%, 83.33%, 73.02%, and 40.00%, respectively. Strain HY-02 seemed safe for four crops (Hordeum vulgare L., Triticum aestivum L., Vicia faba L., and Pisum sativum L.), but not for Brassica napus L. The strain was identified as Alternaria alternata (Fries) Keissler. Scanning electron microscope observations showed that hyphae invaded leaf tissues from the stomata by destroying epidermal cells. Hyphae rapidly grew and invaded living tissues by obtaining nutrients from the tissues, destroying the whole leaf tissues, and finally forming reticular lesions. Therefore, the HY-02 strain has the potential to be developed into microbial biocontrol agents for weed control.     

南方锦天牛触角感器的类型及超微结构

为进一步了解油茶上新发现的蛀干害虫南方锦天牛Acalolepta speciosa的定位及识别寄主和求偶等行为，利用体视显微镜和扫描电镜对其雌、雄成虫触角形态和感器的分布及种类进行观察和比较。结果显示，南方锦天牛雌、雄成虫触角的总长度平均分别为41.96 mm和47.33 mm，雄成虫触角的平均总长度显著长于雌成虫。在成虫触角上共观察到5种类型14个亚型的感器，其中雌成虫触角上有4种感器，分别为毛形感器（4个亚型）、刺形感器（4个亚型）、锥形感器（4个亚型）和Böhm氏鬃毛；雄成虫触角上除以上4种感器外还有1种腔锥形感器；不同类型感器的数量依次为毛形感器>刺形感器>锥形感器>Böhm氏鬃毛>腔锥形感器，但数量在雌、雄成虫之间无显著差异。毛形感器在南方锦天牛雌、雄成虫触角上的数量最多，表明其在接收性信息素或寄主挥发物方面具有重要作用。