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Catches of Male Rice Leaffolders with Virgin Females-baited Traps
No full text於田間利用瘤野螟雌女蛾為誘蟲源進行誘捕雄蟲試驗，結果發現雄蟲對處女蛾誘蟲器具強烈反應。誘捕雄蟲效率與誘蟲源及捕蟲陷阱均具密切關連。捕蟲陷阱以使用直徑60cm以上之圓形水盤漆成黃色者效果最佳，其放置高度以與水稻株高相同者最優。誘蟲源之處女蛾以裝置於周圍開設紗窗之塑膠瓶（罐）(直徑約10cm，高12cm)，並以沾有10%蜜水之棉球供食滷濰持較長之壽命。處女蛾以羽化後第3~4天者誘引力最強，經交尾之雌蟲對雄蟲亦有誘引力，但略較處女蛾為差。每誘蟲器使用8~10隻處女蛾誘捕雄蟲數為使用2~4隻者之2至18倍。誘蟲器之捕獲雄蟲時間主要出現於下半夜，但其開始誘捕到雄蟲的時刻及誘捕高舉之出現時間隨溫度之下降而提早。最低可誘到雄蟲之溫度約在13℃左右。以五隻處女蛾為誘蟲源之誘捕雄蟲有效距離在5m範圍以內。比較吸式誘蟲燈與處女蛾誘蟲器偵測瘤野螟成蟲田間族群初步結果，顯示在田間族群密度較低時以吸式誘蟲燈較佳，但在其族群密度較高時則雌女蛾誘蟲器捕獲蟲數較多。
Methods for trapping males of rice leaf folder, Cnapharocrocis, nedinalis, with virgin females-baited traps were studied in paddy fields. . Trapping effeciency was observed to be closely related to both the source of attractant and the trap designs. Among five different traps tested, the trap of a circular yellow water-pan (more than 60 cm in diameter) was most effective in capturing the male moths. Traps placed at height of 70 cm, near the tops of rice plant, had caught more males than those placed 30 cm either higher or lower the plants. The virgin females being confined in a windowed plastic can and fed with 10% honey-solution had a longer life-span than those caged in a small net bag. Three to four days old virgin females were more attractive. The trap baited with mated females also attracted male moths, but it caught only a half number of males as compared with that of the virgin females. The traps baited with 8 to 10 virgin females caught 2 to 18 times more males than the traps baited with 2 or 4 females. The male moths were caught in the trap from midnight to about 4 AM. The capture occured about one hour earlier when the ambient temperature declihed in late autumn. The trap remained having its fuction of male catch as the temperature declined to about 13℃. Effective distance for the trap baited with 5 virgin females was measured to be within a distance of 5 meters. As seasonal occurrence of the rice leaffolder was monitored with the virgin females-baited trap in comparison with a suction light trap (fluorecents-10W), the virgin females-baited trap seemed to be more effective when the adult population in the fields was high in autumn, but was not as effective as the suction light trap during low adult population period in spring and summer seasons
Observations on the Ecology of Citrus red mite (Panonychus citri (McGregor)) In Taiwan
No full text1．柑桔紅蜘蛛為世界性柑桔重要害蟲之一，本省處於亞熱帶，具海洋性氣候，極適其繁衍，由於世代短，繁殖力強，易對藥劑產生抗性，又乏天敵控制，是以成為本省目下最難防除之柑桔害蟲。
2．嘉義地區室內飼養結果，每年可發生25代，各世代，各蟲期所歷時間之長短，受當時溫度所影響，變異極大。據觀察雌蟲壽命平均為24.09天，產卵日期平均為20.36天，一生總產卵數平均為62.00粒；卵期為5.40天，幼蟲期為2.37天，前若蟲期為2.11天，後若蟲期為2.28天。由卵至成蟲期，雌蟲平均為12.21天，雄蟲平均為11.31天。
3．由卵至成蟲，須脫皮三次，但部份雄蟲僅脫皮兩次由後若蟲靜止期（Deutochrysalis）直接蛻變為成蟲。雄蟲蛻變為成蟲後，即尋雌蟲交尾，與雄蟲交尾之雌蟲，其後代大部發育為雌蟲；未與交尾之雌蟲，其後代則全部發育為雄蟲。由室外採回個別飼養之雌成蟲，觀察178隻結果，其後代之性比率為雌：雄＝2.2:1。
4．柑桔類中，以甜橙類受柑桔紅蜘蛛為害最重，一般成蟲及幼蟲均集中於葉片為害；無論成蟲幼蟲或卵，葉面棲息數均較葉背略多。
5．果園管理優劣，農藥使用不當，庇陰有無，及葉齡之不同，均直接影響柑桔紅蜘蛛之發生與分佈；果園管理妥善，農藥使用頻繁及無庇陰之果園柑桔紅蜘蛛發生多，在嫩葉上與中齡葉片上紅蜘蛛的密度較在考葉上者為高。
6．自民國53年5月至54年6月觀察結果，以11月至5月因雨量分佈少，發生密度較高，6月至10月由於颱風豪雨之夾襲，發生密度較低。在本省氣候情況下，能以有效影響柑桔紅蜘蛛密度之氣象因子，以雨量為主。
According to the laboratory rearing the citrus red mite took 25 generations from 5, Oct. 1964 to 15, Oct. 1965, at the average temperature and relative humility of 18-30℃ and 64-80 per cent. The average number of eggs laid by each female was 62, the range being from 18 to 87, and the average number of eggs laid by each female per day was 3.06, the range being from 0 to 14. Eggs generally hatched from 2 to 15 days, with an average of 5.40 days, and the stages of larva, protonymph, deutonymph took an average of 2.37, 2.11, 2.28 days, ranging 1-7, 1-6, 1-9 days, respectively. The time required for egg to adult average 12.21 days in female, ranging from 7 to 30 days, while in male, it took average of 11.31 days, ranging from 6 to 23 days.
Based on one year’s observation, it was found that the citrus red mite took about one month to complete a life-cycle during December, January and it took more than two generations each of the other months.
Both sexes of citrus red mite were found to have a larval and two nymphal stages. each followed by a resting stage. Some male could mature without the stage of deutonymph .instar. Mating process was usually accomplished immediately after the last molt of the female; Eggs from unfertilized female gave rise to males only and those from fertilized feia1e to a preponderance of females.
Field obsevations revealed that citrus red mites usually build-up more dense and large colonies in the well managed citrus orchard, plants rceived plentiful sunlight, and younger leaves; in neglected orchard, shaded plants, and older leaves, mites generally are scarce. Applications of insecticide in dis-order were also conductive to increase of mite population.
The climatic data in central and southern part of this island indicated that both temperature and humidity were very suitable for citrus red mite to develop all the year round, and the rainfall seems to be the major factor that directly influenced the seasonal fluctuation of mite’s populations. It was found that citrus red mite’s population on Valencia orange trees tended to be the highest during the dry late-fall, winter, and spring seasons, and the raininess or that accompanied with the result of typhoon were noted to have reduced the spring population and
maintained a low population through-out the sunmer
Changes in spectral characteristics of rice canopy infested with brown planthopper and leaffolder
No full textPotted experiments of rice (Oryza sativa L.) plants were conducted to produce various scales of brown planthopper [Nilaparvata lugens (Stal), Homoptera:Delphacidae] and leaffolder [Cnaphalocrosis medinalis Guenee (Lep., Pyralidae)] infestations, respectively, for canopy hyperspectral reflectance measurements, and then to identify spectral characteristics (SCs) associated with insect infestations leading to the establishment of spectral models for severity assessment. By linear correlation intensity analysis, correlation coefficients (r) along the spectral domain of 350 to 2400 nm were determined and narrow bands related to infestation severity were selected as SCs. The reflectance at green light (490-560 nm) maximum (R-GREEN), red light (640-740 nm) minimum (R-RED), and near-infrared (740-1300 nm) peak (R-NIR) were also considered. For canopies infested with brown planthopper, r value at 426 nm was the highest (r=0.878**). Among the calculated spectral indices using two SCs, the determination coefficient of R-NIR/R-RED ratio was the highest (R-2-0.922, P < 0.001). For leaffolder infested canopies, the most negative r value located at 757 nm (r=0.613*) in active tillering stage but shifted to 445 nm (r=0.928**) in heading stage. The index R-NIR-R-RED in the active tillering increased R-2 value to 0.422 (P < 0.001), while no increase in R-2 was found in the examined SIs in heading stage. Models with more than two SCs yielded from multiple linear regression analysis exhibited a further improvement for discriminating infestation severity
An Injury Equivalency System for Establishing a Common Economic Threshold for Three Species of Rice Planthoppers (Hemiptera: Delphacidae) in Taiwan
No full textThe economic threshold (ET) for multiple pest species that share the same injury type on host plants (feeding guild) has been proposed for decision-making in integrated management framework of many defoliating insect pests. However, only a few consider agricultural pests with sucking mouthparts. This study presents the first injury equivalency system for the feeding guild made up of three rice (Oryza sativa L.) planthopper (Hemiptera: Delphacidae) species-Nilaparvata lugens (Stål), Sogatella furcifera (Harváth), and Laodelphax striatellus (Fallén)-by using relative amount of honeydew excretion of each species. The intraspecific injury equivalent coefficient was determined; this coefficient provides an exchange rate for different developmental stages in a species. N. lugens was chosen as the standard species to obtain interspecific injury equivalents for other individuals in the guild, allowing estimates of total guild injury feasible. For extension purposes, the injury equivalency was simplified by pooling all nymphs and adults in the guild to mitigate the potential confusion resulting from uncertainty of instars or wing form. A matrix of ETs established on previous studies and incorporating changes of management cost and rice price was used and served as a control decision guide for the guild samples. The validity of the proposed injury equivalency system was tested using several field data sets, and the results are generally promising and meaningfully elevate the accuracy of estimating combined injury and damage to rice, suggesting that the proposed system is a better integrated pest management decision-making system compared with conventional practices
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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