Distribution of invertebrates on foliage in forests of south-eastern Australia

Nearly 1500 foliage samples were collected from a total of 156 plant species, distributed at 16 study sites representing a wide range of forests and woodlands in south-eastern Australia. Samples were collected in all months. Invertebrates present in samples were counted, sorted into 13 categories, and the number present (> 3 mm in length) converted into density estimates. Densities of all invertebrates combined and invertebrate diversity were also calculated. Despite high variability there were some obvious distributional patterns for most categories. Three major dichotomies affected abundance and distribution of invertebrates: these were presence or absence of flowers, whether the plant species was Eucalyptus or other, and if Eucalyptus, whether the plant species was Symphyomyrtus or Monocalyptus. The presence of flowers in foliage samples increased the abundance of most invertebrate taxa. Compared to foliage of non-Eucalyptus species, Eucalyptus foliage had more lerp-forming psyllids and miscellaneous larvae, but fewer Arachnida, Coleoptera, Psocoptera, Hemiptera (other), Thysanoptera, Diptera, and total arthropods. Foliage of Symphyomyrtus species had higher densities of most categories (and particularly lerp-forming psyllids) than that of Monocalyptus. There were seasonal variations in abundance in most invertebrate taxa, but these patterns were different for Eucalyptus and non-Eucalyptus species. For most sites abundance of all arthropods combined was lowest in winter, but this decline was not especially pronounced, and was reversed at more xeric sites. For most categories there were significant differences between study sites in abundance and for some this was related to position of sites on a moisture gradient. In general total arthropod densities were highest at intermediate and xeric sites. There were some significant differences in arthropod communities for the same plant species at different study sites. Sample height, plant height, and the ratio of these were relatively unimportant variables. Likewise, the ratio of leaf width: leaf length was not significantly correlated with abundance for any invertebrate category across 128 plant species, but mean leaf size was negatively correlated with densities of Arachnida and total invertebrates. The distributions of some invertebrate categories were inter-correlated.     

Crossing experiments in Allium L. section Cepa

VAN RAAMSDONK, L. W. D., WIETSMA, W. A. & DE VRIES, J. N., 1992. Crossing experiments in Allium L. section Cepa . A full diallel was carried out with six diploid species of Allium section Cepa and A. roylei of section Rhizirideum , High isolation barriers were found between the related species A. cepa and A. oschaninii , between A. oschaninii and A. vavilovii , and between A. galanthum and A. pskemense . On the contrary, the species A. cepa and A. roylei , belonging to different sections, show only slight isolation barriers. The Wallace effect, which is the development of internal isolation barriers as such, is likely to have taken place in the evolution of A. oschaninii and A. vavilovii , and possibly also between A. galanthum and A. pskemense .     

吉林省粘虫猖獗世代发生虫源的研究——Ⅰ.发生虫源的探讨和越冬问题研究

粘虫是吉林省粮食作物的大害虫。本文为作者于1953—1962年研究粘虫的一部分工作,目的在于分析吉林省粘虫发生猖獗世代的虫源问题。我们怀疑春季出现的大量成虫有两种可能来源:(1)本地越冬的成虫、蛹或幼虫;(2)由外地迁入。通过研究分析,所得结果如下: 1.粘虫在吉林省一年完成两个世代。春季发生的第一代是猖獗世代,幼虫为害盛期在6月下旬至7月上旬,其繁殖虫源主要来自5月下旬到6月上半月出现的成虫。 2.粘虫在当地的入冬虫态,有幼虫、蛹及成虫。经过发生地的越冬调查及野外试验,证明粘虫在东北和内蒙地区的自然条件下不论何种虫态,均不能越冬。 3.据粘虫抗寒力测定,在-8℃恒温下,幼虫、蛹、成虫均迅速死亡,在-5℃下最长只能存活3—7小时,在1±1℃下全部死亡的理论时间为成虫19.95天、幼虫44.67天、蛹25.70天。查当地1、2两月旬平均气温最高-9.4℃,最低-16.5℃,田间5厘米深的土温为-12.4—-9.4℃,均超过虫体的死亡低温。 因此,粘虫不可能在吉林省越冬,从而可以推断猖獗世代的虫源,是由外地迁入的。     

Short-Term In Vitro Culture and Molecular Analysis of the Microsporidian, Enterocytozoon bieneusi

ABSTRACT. The microsporidium, Enterocytozoon bieneusi , causes a severe, debilitating, chronic diarrhea in patients with the acquired immunodeficiency syndrome. Specific diagnosis of intestinal microsporidiosis, especially due to Enterocytozoon , is difficult and there is no known therapy that can completely eradicate this parasite. Preliminary studies indicate that a short term (about 6 months) in vitro culture of this parasite yielding low numbers of spores, may be established by inoculating human lung fibroblasts and/or monkey kidney cell cultures with duodenal aspirates and or biopsy from infected patients. The cultures may subsequently be used for the isolation and molecular analysis of parasite DNA.     

东亚飞蝗Locusta migratoria manilensis Meyen循环系统和排泄器官的解剖和组织构造

接着东亚飞蝗消化系统和生殖系统之后,现在把循环系统的解剖和组织构造整理出来以供参考,由于排泄器官相当分散,与循环系统又有一定的连系,所以也附带在本文中叙述。 前人对于昆虫的循环系统研究工作可以参考的有 Albrecht(1953)所著飞蝗解剖一书;Snodgrass(1903)作过 Dissosteria carolina 的内部解剖;Hodge(1936、1939、1940)对