扬州口岸从进境蓝湿牛皮及其外包装上截获国内分布未广的5种锯谷盗

叙述了从进境蓝湿牛皮及其外包装上截获国内分布未广的5种锯谷盗,它们分别是三星谷盗Psammoecus triguttatusReitter、双齿谷盗Silvanus bidentatus(Fabricius)、大眼谷盗Silvanus lewisiReitter、小眼谷盗Silvanus recticollisReitter、缢胸谷盗Silvanus difficilisHalstead。     

益蝽对番茄潜叶蛾的捕食行为及捕食能力研究

为明确捕食性天敌昆虫益蝽Picromerus lewisi对番茄潜叶蛾Tuta absoluta幼虫的生防潜能,在室内开展了益蝽对不同龄期番茄潜叶蛾幼虫的捕食功能反应、搜寻效应以及防治潜力研究。结果表明,益蝽5龄若虫、雌雄成虫对番茄潜叶蛾4龄幼虫的捕食功能模型均符合Holling Ⅱ模型,其中,益蝽5龄若虫的捕食能力更强,表现为瞬时攻击率和控害效应最高,为1.112和48.35。且益蝽5龄若虫对番茄潜叶蛾2龄和3龄幼虫的捕食功能模型也符合Holling Ⅱ模型,其控害效应为2龄（155.67）＞3龄（79.87）＞4龄（48.35）,益蝽5龄若虫对番茄潜叶蛾2~4龄幼虫的日最大捕食率均可达85%以上,搜寻效应随番茄潜叶蛾幼虫密度的增加而降低,对番茄潜叶蛾3龄幼虫的搜寻效应大于2龄和4龄幼虫。另外,益蝽5龄若虫的捕食作用受自身密度因素干扰,随着自身密度的增加,其相互干扰作用增强,单头捕食率下降。综上,益蝽4龄和5龄若虫、雌雄成虫均能捕食番茄潜叶蛾,其中益蝽5龄若虫对番茄潜叶蛾不同龄期幼虫具有较好的捕食作用,尤其是2龄幼虫,对潜叶状态的番茄潜叶蛾也具有一定防治作用,本研究可为益蝽对番茄潜叶蛾的绿色防控提供理论依据。     

Cell cycle and cleavage events during in vitro cultivation of bloodstream forms of Trypanosoma lewisi,a zoonotic pathogen

Trypanosoma (Herpetosoma) lewisi is a globally distributed rat trypanosome, currently considered as a zoonotic pathogen; however, a detailed understanding of the morphological events occurring during the cell cycle is lacking. This study aimed to investigate the cell cycle morphology and cleavage events of Trypanosoma lewisi (T. lewisi) during in vitro cultivation. By establishing in vitro cultivation of T. lewisi at 37°C, various cell morphologies and stages could be observed. We have provided a quantitative analysis of the morphological events during T. lewisi proliferation. We confirmed a generation time of 12.14 ± 0.79 hours, which is similar to that in vivo (12.21 ± 0.14 hours). We also found that there are two distinct cell cycles, with a two-way transformation connection in the developmental status of this parasite, which was contrasted with the previous model of multiple division patterns seen in T. lewisi. We quantified the timing of cell cycle phases (G1_n, 0.56 U; S_n, 0.14 U; G2_n, 0.16 U; M, 0.06 U; C, 0.08 U; G1_k, 0.65 U; S_k, 0.10 U; G2_k, 0.17 U; D, 0.03 U; A, 0.05 U) and their morphological characteristics, particularly with respect to the position of kinetoplast(s) and nucleus/nuclei. Interestingly, we found that both nuclear synthesis initiation and segregation in T. lewisi occurred prior to kinetoplast, different to the order of replication found in Trypanosoma brucei and Trypanosoma cruzi, implicating a distinct cell cycle control mechanism in T. lewisi. We characterized the morphological events during the T. lewisi cell cycle and presented evidence to support the existence of two distinct cell cycles with two-way transformation between them. These results provide insights into the differentiation and evolution of this parasite and its related species.     

The Relation of Agglutinins to Antigenic Variation of Trypanosoma lewisi*

SYNOPSIS. During the course of infection in the rat, Trypanosoma lewisi produces 2 antigenic variants: the 1st represents the initial, reproducing population of cells; and the 2nd the nonreproducing, ablastin-inhibited adult population. The specificities of the agglutinins elicited by the variants were studied by adsorption and agglutination methods and the newer immunoelectroadsorption technic. It was found that the reproducing variant has a surface antigen that reacts with the agglutinin specific for the adult variant, but this antigen does not become immunogenic until transformation to the adult variant occurs. It was also found, with fractions of immune sera obtained by gel filtration, that the agglutinin specific for the reproducing variant is IgG and that specific for the adult variant, IgM. The antigenic variants of pathogenic and nonpathogenic trypanosomes are compared, and the roles of trypanocidal and ablastic antibodies in the induction of antigenic variation are discussed.     

室内条件下莱氏猛叩甲对松墨天牛和黄粉虫的捕食能力

【目的】本研究旨在明确莱氏猛叩甲Tetrigus lewisi老熟幼虫分别对黄粉虫Tenebrio molitor和松墨天牛Monochamus alternatus末龄幼虫和蛹的捕食量的差异,评估莱氏猛叩甲的捕食能力,为松墨天牛M.alteratus的有效治理找到潜在的高效生物防治因子。【方法】于2014年11月在浙江富阳昌东村马鞍山砍下松墨天牛虫害木,通过林间野外调查,明确松墨天牛和莱氏猛叩甲的发生情况;将野外采集到的莱氏猛叩甲幼虫带回室内,分别饲喂黄粉虫和松墨天牛的末龄幼虫和蛹,每天记录捕食量,确定莱氏猛叩甲的捕食能力。【结果】野外调查中,我们在松墨天牛幼虫蛀食的坑道中发现了莱氏猛叩甲幼虫和松墨天牛幼虫被取食后的残体;在采集到1 094头松墨天牛幼虫的危害木内,共采得莱氏猛叩甲末龄幼虫36头,约为松墨天牛幼虫数量的3%。室内捕食实验表明,5 d内莱氏猛叩甲捕食黄粉虫幼虫总量为3.2头,平均每天捕食约0.6头,而捕食松墨天牛幼虫总量为8.0头,平均每天捕食约1.6头,莱氏猛叩甲对松墨天牛的总捕食量显著高于对黄粉虫幼虫的总捕食量(P0.0001);4 d内莱氏猛叩甲捕食黄粉虫蛹总量为5.6头,平均每天捕食约1.4头,而捕食松墨天牛蛹总量为7.8头,平均每天捕食约2.0头,莱氏猛叩甲对松墨天牛蛹的捕食量显著高于黄粉虫蛹(P=0.028)。回归分析还表明,莱氏猛叩甲幼虫的捕食量不受叩甲个体大小的影响。【结论】莱氏猛叩甲普遍分布在松墨天牛发生区,同时发现松墨天牛被取食后的残体,表明莱氏猛叩甲是松墨天牛的捕食性天敌。莱氏猛叩甲均能捕食黄粉虫和松墨天牛的幼虫和蛹;相比于捕食黄粉虫,莱氏猛叩甲对松墨天牛的幼虫和蛹具有更好的捕食效率,具有很好的生物防治前景,是未来松墨天牛治理潜在高效生物防治因子。     

Crossed immunoelectrophoretic analyses of antigens from Trypanosoma lewisi and Trypanosoma musculi

Trypanosoma lewisi and Trypanosoma musculi were collected from immunosuppressed infected hosts and extracted with phosphate buffered saline. Antisera were obtained from rats repeatedly infected with T. lewisi or mice repeatedly infected with T. musculi. Cellular antigens (CAg) present in the extracts of the parasites were analyzed by microimmunodiffusion (MID), crossed immunoelectrophoresis (CIE) and tandem crossed immunoelectrophoresis (TCIE). Trypanosome extracts were absorbed with the heterologous hyperimmune antisera to examine shared and unique antigens of the parasites.

Extracts of T. lewisi formed four precipitin lines when reacted with hyperimmune rat antiserum and three precipitin lines were detected by mouse anti-T. musculi serum in MID analyses. T. musculi extract formed two precipitin lines with mouse hyperimmune serum and two precipitin lines with rat anti-T. lewisi serum in the MID tests. When T. lewisi was reacted with the homologous hyperimmune rat antiserum in CIE, 14 precipitin peaks developed, while T. musculi extract formed eight peaks with homologous mouse hyperimmune serum. Seven precipitin peaks developed when T. lewisi extract was reacted with the mouse antiserum and T. musculi extract formed eight peaks during its electrophoretic migration into rat anti-T lewisi serum. TCIE clearly showed that five T. lewisi CAg could not be detected in the T. musculi extract by the rat antiserum, while mouse anti-T. musculi serum formed six precipitin peaks with the T. lewisi extract and seven peaks with the homologous extract. One of the CAg present in the T. musculi extract was not found in the T. lewisi extract. Absorptions of the extracts with heterologous antisera and subsequent CIE against the homologous antisera indicated three of the CAg of T. lewisi were not shared by T. musculi, while a single antigen of T. musculi was not detected in T. lewisi. Although concentrations of antibodies in each of the antisera and CAg in the parasite extracts were not equivalent, the data indicated that a minimum of eight CAg are shared by these rodent trypanosomes and at least three antigens appeared to be unique to T. lewisi and a single antigen to T. musculi.     

松褐天牛的捕食性天敌莱氏猛叩甲的生态位

经野外调查结合室内实验发现莱氏猛叩甲Tetrigus lewisi Candèze为松褐天牛Monochamus alternatu Hope的捕食性天敌。且莱氏猛叩甲还可取食马尾松角胫象Shirahoshizoinsisiosus(Voss)和松幽天牛Asemumamuren Kraatz。室内试验表明,1头莱氏猛叩甲在4个月左右的时间内最多可取食17头松褐天牛。林间,该叩甲在马尾松衰弱木上的种群密度为平均3～4头/株,以树干3m以下分布较多。通过对其空间生态位的研究发现该虫与松褐天牛的空间生态位宽度相当,且这2种昆虫的生态位重叠值和生态位的比例相似性较大。