6,205 research outputs found
Architectural illustrations... 1899
No full textArchitectural illustrations / A.W. Leh. [s.l.] : The author, 1899. 1 leaf, 23 plates ; 21 x 29 cm
Monitoring the control methods of Heterobasidion annosum s.l. root rot
No full textThis thesis summarises the author's work on the effectiveness of two control methods against the necrotrophic fungal pathogen Heterobasidion annosum s.l. (Fr.) Bref. The studied control methods were stump treatments through the application of a fungal biocontrol agent (Phlebiopsis gigantea) and application of urea solution. An additional component to this thesis was to develop a useful Agrobacterium tumefaciens-mediated transformation system for the H. annosum s.l. The potential risk for a build-up in the capacity of H. annosum s.l. to resist overgrowth by P. gigantea was investigated by utilising a P. gigantea strain used in the commercial preparation Rotstop and different strains of H. annosum s.l. The impact on intraspecific genetic diversity from the P. gigantea used in Rotstop four years after stump treatment was estimated using both microsatellite markers and AP-PCR. The long-term effect of urea treatment during first rotation thinning of Picea abies stands was evaluated 15 years post-treatment. An A. tumefaciens-mediated transformation system was developed using two different transformation plasmids and a North American H. annosum strain. The results revealed differences between H. annosum s.l. strains in their ability to resist overgrowth by P. gigantea. This trait was found to be heritable which suggests that H. annosum s.l. has the capacity to develop more tolerant strains against the biocontrol agent if the conditions are met. Also, one QTL effect associated with this trait was identified. Genetic diversity was lower within Rotstop treated plots and the resident population was more genetically similar to the applied P. gigantea strain than other populations sampled in Sweden. This effect on genetic structure was not detected 100-200 m from the treated plot which suggests that stump treatments with P. gigantea only has a local effect on genetic diversity. Urea treated plots exhibited less rot than untreated plots and the urea treatments also significantly reduced the occurrence of windthrown trees. This shows that urea treatment during thinning operations is an efficient method to reduce root rot in P. abies stands. A total of 18 H. annosum s.l. transformants were obtained from the A. tumefaciens-mediated transformation system. The transformants expressed GFP throughout the mycelia and had a normal growth rate. This system will be very useful for genomic work and interaction studies
Reproductive isolation between sympatric and allopatric Brazilian populations of Lutzomyia longipalpis s.l. (Diptera: Psychodidae)
No full textLutzomyia longipalpis s.l., the main vector of Leishmania chagasi
in Latin America, is a species complex although the exact number of
siblings is yet unknown. In Brazil, the siblings differ in male
copulatory courtship songs and pheromones that most certainly act as
pre-zygotic reproductive barriers. Here we analysed the reproductive
isolation between three allopatric and two sympatric populations of Lu.
longipalpis s.l. from Brazil. The results indicate a strong copulatory
and pre-mating isolation between the three allopatric populations. In
addition, the results also indicate a stronger pre-mating isolation
between the two sympatric siblings than between the three allopatric
ones, suggesting a role for reinforcement in the speciation of the Lu.
longipalpis s.l. complex
Reproductive isolation between sympatric and allopatric Brazilian populations of Lutzomyia longipalpis s.l. (Diptera: Psychodidae)
No full textLutzomyia longipalpis s.l., the main vector of Leishmania chagasi in Latin America, is a species complex although the exact number of siblings is yet unknown. In Brazil, the siblings differ in male copulatory courtship songs and pheromones that most certainly act as pre-zygotic reproductive barriers. Here we analysed the reproductive isolation between three allopatric and two sympatric populations of Lu. longipalpis s.l. from Brazil. The results indicate a strong copulatory and pre-mating isolation between the three allopatric populations. In addition, the results also indicate a stronger pre-mating isolation between the two sympatric siblings than between the three allopatric ones, suggesting a role for reinforcement in the speciation of the Lu. longipalpis s.l. complex
From Insect to Pest: Pest and Pest Control in Colonial Taiwan
No full text本文欲由「建構論」出發，說明「害蟲」實為19世紀下半葉才慢慢在東亞出現的新概念和新語彙。以臺灣為例，後世被認為危害甚烈的「螟」蟲，雖然明清時期的文獻記載甚夥，但多半集中在轉化為比喻養子的「螟蛉子」風俗，而與農害無涉。今人或以為清朝無「科學」知識，故對蟲害無所知覺，然若執此一端，則輕忽了其間隱含的觀念變化。由「螟蛉」轉為「螟害」，正是日本殖民統治下，將「害蟲」這個概念傳入後而來。近代國家的出現，殖民統治、都市化、戰爭需求，以及近代農學知識的轉型與應用昆蟲學的形成等多重因素的交會，才逐漸產生「害蟲」的概念。日本殖民統治臺灣時期，「蟲害」發生的頻率和種類不斷增加，實因應用昆蟲學讓原本早已存在於臺灣的昆蟲轉為害蟲。面對這些重新被界定、挖掘出來的害蟲，殖民政府透過制度的力量，包括頒布害蟲預防法規，設立農業試驗場、植物檢查所以及害蟲巡視員等組織，試圖防堵壓制「害蟲」對農作造成的損失。1920年代以降，日本化學工業突飛猛進，無機及有機化合物製成的農藥開始大行其道，臺灣的應用昆蟲學專家也不遺餘力地介紹各式新農藥產品。不過，農藥在不同農作物的應用情形並不一致，臺灣只有在柑橘瓜果等進入國際市場的農作物採取了「先進」的劇毒農藥，食糧作物中的水稻則仍維持傳統的人力防除法，而與日本國內廣泛使用農藥的趨勢不同，這或許是殖民地與母國在都市化及農業商品化速度不同的表現。This paper argues that the concept of “pest” in East Asia is a constructive idea that gradually emerged from the late nineteenth century. Take Taiwan for example; there are a lot of records from the Ming and Qing period concerning the moth. However, in contrast to the identification of the moth as pest in the twentieth century, most of these older records describe the moth (or mulberry insect, mingling, 螟蛉) as the adopted son (yangzi), a metaphor originated from the Book of Odes, which is irrelevant to the notion of “pest”. To simply criticize our predecessors lack of “scientific knowledge” would disregard the subtle transformation of the concept from “moth” to “pest.” In fact, “pest” was a novel idea introduced into Taiwan during the Japanese colonial rule. Six factors contributed to the emergence of “pest”: the birth of the modern nation-state, colonial control, urbanization, industrialization, preparation for war, and the emergence of scientific agriculture and entomology. With this new perspective, new pests were incessantly “discovered” by Japanese entomologists and the frequency of pest damage was ever and increasingly growing. Alarmed by the damage and loss of agricultural productivity caused by such pests, the Japanese colonial government tried to prevent and control the pests by the following institutional and administrative measures: issue regulations for preventing and eliminating the pests, establish agriculture laboratories and quarantine stations, and organize “pest patrols” to monitor and warn about potential pest damage. Thanks to the enormous strides of the Japanese chemical industry during the interwar period, organic and inorganic pesticides were widely adopted by Japanese farmers, and the entomologists concomitantly introduced pesticide products into Taiwan. However, the degree of pesticides application varied widely in different agricultural sectors in Taiwan. As an international commodity, oranges, for example, were heavily fumigated with poisonous cyanide gas; but pests in paddy land were continuingly treated by manual and labour inputs, which was quite different from their Japanese counterpart, who intensively applied various chemical pesticides. This variation and difference indicates a sharp contrast between Japan and Taiwan, and reflects the different effect of urbanization and agricultural commercialization in the two places
Festuca ovina L., s.l. en Festuca rubra L., s.l. in Nederland
No full textThe author gives a survey of the taxa belonging to Festuca ovina L., s.l. and F. rubra L., s.l. as they occur in the Netherlands. Four species are distinguished, viz. F. ovina L., F. trachyphylla (Hack.) Kraj., F. heterophylla Lamk., and F. rubra L. F. ovina L. is represented by 3 subspecies, subsp. tenuifolia (Sibth.) Čelak., subsp. ovina, and subsp. cinerea (Vill.) Duyfjes, nov. comb.; F. rubra L. can be subdivided into 2 subspecies, subsp. rubra and subsp. juncifolia (St. Am.) R. Lit.
Of these taxa F. heterophylla is most probably introduced with grass-seeds; the others are native
Qin ding qian lu /
No full textSpecial collection from London Missionary Society.; On double leaves, oriental style, in case.; Also available in an electronic version via the Internet at http://nla.gov.au/nla.gen-vn1920561.880-02 Qian lu
Molecular analysis of an odorant-binding protein gene in two sympatric species of Lutzomyia longipalpis s.l.
No full textLutzomyia longipalpis s.l. is the main vector of American visceral leishmaniasis (AVL) and occurs as a species complex. DNA samples from two Brazilian sympatric species that differ in pheromone and courtship song production were used to analyse molecular polymorphisms in an odorant-binding protein ( obp29 ) gene. OBPs are proteins related to olfaction and are involved in activities fundamental to survival, such as foraging, mating and choice of oviposition site. In this study, the marker obp29 was found to be highly polymorphic in Lu. longipalpis s.l. , with no fixed differences observed between the two species. A pairwise fixation index test indicated a moderate level of genetic differentiation between the samples analysed
Fu gu bian : [2 juan] : fu jiao zheng, fu lu /
No full textFu: Zeng yue xuan gao / Zhang Wei zhuan -- An lu ji / Zhang Xian zhuan.Mode of access: Internet
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