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澳门特别行政区园林绿化植物病虫害调查初报   总被引:4,自引:0,他引:4  
莫贱友  李焜华  郭堂勋   《广西植物》2006,26(6):702-705,706
对澳门主要区域园林绿化植物病虫害进行的初步调查,共采集到病害标本85份,昆虫标本315份,鉴定确认危害澳门园林植物的病害有64种,害虫77种;其中还发现属于检疫对象的椰心叶甲为害椰树。并对发生较普遍和严重的病虫害提出了一些防治措施和建议。  相似文献   

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Most of the recent applications of mathematical optimisation theory to the optimal or other control of pests and infectious diseases are surveyed here. Comments are made on some of the difficulties encountered in solving the resulting mathematical problems and in applying the relevant conclusions to real biological systems. At the end of the survey some further problems are suggested whose study might give satisfaction to both mathematicians and those interested in the practical problems of controlling biological populations.  相似文献   

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广西杧果病虫害调查初报   总被引:1,自引:0,他引:1  
对广西24个市(县)杧果病虫害进行了系统的调查。发现病害有20种,主要为白粉病、炭疽病、细菌性角斑病、蒂腐病等,其中杧果水泡病、杧果畸型病和杧果红点病为国内新发现的杧果病害;发现害虫94种,隶属于8目38科,主要为杧果小齿螟Pseudonoorda minor Munroe、杧果横线尾夜蛾Chlumetia transversa Walker、杧果茶黄蓟马Scirtothrips dorsalis Hood、桔小实蝇Dacus dorsalis Hendel、杧果扁喙叶蝉Idioscopus incertus Baker等。腹足纲有害生物1种。  相似文献   

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A multicenter survey of 400 married Filipino women 15-40 years of age conducted in 1986 by Family Health International and the International Health Foundation provided valuable information on contraceptive use in the Philippines, as well as factors influencing such practices. The respondents, who were drawn from 10 urban communities in Metro Manila and 10 rural communities in Nueva Ecija Province, averaged 31.5 years of age and had a mean number of 2.9 children. 32% of respondents indicated they desired another child. 225 women (56%) reported they were using no method of contraception. 59 (14%) were protected from pregnancy by tubal sterilization or vasectomy. 77 women (19%) were oral contraceptive (OC) users, and 8 (2%) were IUD users. Only 1 respondent was using a long-acting contraceptive. 3 women used spermicides, 21 (5%) used condoms, 25 (6%) practiced rhythm, and 30 (3%) of the women's husbands practiced withdrawal. Overall, 27% of contraceptive users in this sample used more than 1 method. 26% had been using a contraceptive method for 1-3 years and another 46% for more than 3 years, indicating consistent acceptance of family planning. A sequential trend of nonuse, OC use, and finally sterilization was observed. OC use was highest among women in their late 20s with 2-3 children. Urban-rural residence and socioeconomic factors had little impact on OC use. An encouraging finding was that only 25% of respondents believed that the pill poses important health risks and 61% were aware that pregnancy and childbirth involve greater health risks than OC use. This finding is in opposition to the extremely high levels of misinformation about the dangers of OC use identified in other surveys in developing countries and probably reflects the fact that 77% of women in the present study reported receiving advice on contraception from family planning professionals.  相似文献   

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Dawes  C. J.  Trono  G. C.  Lluisma  A. O. 《Hydrobiologia》1993,260(1):379-383
Technique improvement and cost reduction of branch culture, micropropagation, and callus production of carrageenan-yielding seaweeds Kappaphycus alvarezii and Eucheuma denticulatum is presented. Low cost branch culture is possible by enriching seawater with 0.1% coconut water with 1 mg l–1 indole-3-butyric acid for 24 h wk–1 or continuous culture with 0.01% Algafer, a Philippine fertilizer. Micropropagation of 0.5 cm explants had almost 100% new branch production demonstrating the viability of callus regenerated plants. The use of carrageenan as a media for callus production was not effective when compared to agar. Propagules of both species, transferred from the University of the Philippine Marine Science Institute (UPMSI) culture facility to the field, showed daily percent growth rates of 5 to 5.5% d–1 over 84 days. Based on the costs of the UPMSI laboratory, a culture facility in the seaweed farming area is estimated to cost about U. S. $22000 during the initial year and 58% less the second year.  相似文献   

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胡蜂Vespidae是重要的捕食性天敌和授粉昆虫,敌害是制约胡蜂种群存活与发育的主要因素之一,弄清胡蜂的敌害种类和危害,可以为下一步防治技术措施的研究提供参考.通过目测法和设监视器等方法对广西胡蜂标准蜂群培育及其野训成为经济蜂群阶段的敌害种类和危害情况进行了初步调查,结果发现,胡蜂的敌害共有33种,其中有害动物19种、有害微生物14种.在标准蜂群野训成为经济蜂群期,对胡蜂危害严重的有害动物为蚂蚁、鸟类、盗虻、蝙蝠及松鼠等,蚂蚁对蜂群的危害最严重、最普遍;在蜂王越冬及标准蜂群培育期,对胡蜂危害严重的病害种类较多,有以色列急性麻痹病毒病、白垩病、欧幼病等,其中危害最严重的是以色列急性麻痹病毒病.14种有害微生物中,有13种病害是蜜蜂群中常见的病害.  相似文献   

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The first two phases of a national prevalence survey of schistosomiasis in The Philippines were completed in Mindanao in 2005 and the Visayas in the first quarter of 2007. The design was a stratified two-step systematic cluster sampling, with two Kato-Katz thick smears examined from each participant. In Mindanao, a total of 22 provinces spread in six regions were covered by the survey with five barangays (equivalent to a village) per province for a total of 110 barangays. The response rate was 70.9% with a total of 21,390 individuals examined. The province of Maguindanao, a known endemic area for schistosomiasis japonica, failed to take part in the survey. In the Visayas, 10 out of 11 provinces, spread out in three regions, participated in the survey. There were 6321 respondents for an overall participation rate of 32.2%. Mindanao showed a wider coverage of the disease than the Visayas (60% versus 45%). By region, Caraga or Region 13 ranked first in Mindanao and Region 8 in the Visayas. By province, Agusan del Sur is first on the list, followed by Northern Samar and then Eastern Samar. Overall, the prevalence rate among males is higher than that of females suggesting the occupational hazard of farming and fishing among the males. The higher exposure among farmers and fishermen is also borne out by the age distribution of the disease. Prevalence remains consistently high among the adults compared with the younger age groups. The survey also covered other helminth infections that can be detected in a stool survey, notably soil-transmitted helminthes and food-borne trematodes.  相似文献   

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A survey was conducted to determine the prevalence of plant-parasitic nematodes associated with vegetable crops grown in organic and conventional farms in Laguna province, Philippines. Seven nematode genera (Aphelenchoides, Aphelenchus, Helicotylenchus, Meloidogyne, Pratylenchus, Rotylenchulus and Tylenchus) from organic farms and five (all those found in organic except Aphelenchoides and Pratylenchus) from conventional farms were isolated using modified Baermann tray method. Among these taxa, Meloidogyne and Rotylenchulus were the most prevalent and abundant in both organic and conventional farms. Pratylenchus was also prevalent in organic farms and Helicotylenchus in conventional farms. Rotylenchulus was found associated with every vegetable in both organic and conventional farms and Meloidogyne was also observed with all vegetables in conventional farms. Organic vegetable farms were more diverse in terms of genera of plant-parasitic nematodes than conventional farms.  相似文献   

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本文对厦门城市绿化主要栽培的棕榈科植物病虫害种类进行系统调查,共计44种病害,17种虫害,为厦门园林棕榈科植物病虫害的防治和深入研究提供了重要依据.  相似文献   

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The worldwide production of the gelling agent agar mainly rely on the red algae of the order Gracilariales and Gelidiales for raw material. We investigate here the potential of a species from another red algal order, Ceramiales as an agar source. The agar from Laurencia flexilis collected in northern Philippines was extracted using native and alkali treatment procedures and the properties of the extracts were determined using chemical, spectroscopic and physical methods. The native agar, 26% dry weight basis, forms a gel with moderate gel strength (200 g cm?2). Alkali‐treatment did not enhance the gel strength, indicating insignificant amounts of galactose‐6‐sulfate residue, the precursor of the gel‐forming 3,6‐anhydrogalactose (3,6‐AG) moieties. Furthermore, the Fourier transform infrared and chemical analysis showed low sulfate and high 3,6‐AG levels, not affected significantly by the alkali treatment. Nuclear magnetic resonance spectroscopic analysis revealed 3‐linked 6‐O‐methyl‐D‐galactose and 4‐linked 3,6‐anhydro‐L‐galactose as the major repeating unit of the native extract, with minor sulfation at 4‐position of the 3‐linked galactose residues. The native and alkali treated agars have comparably high gelling and melting temperatures, whereas the former exhibits higher gel syneresis. Laurencia flexilis could be a good source of agar that possesses physico‐chemical and rheological qualities appropriate for food applications. Due to the inability of alkali treatment to enhance the key gel qualities of the native extract, it is recommended that commercial agar extraction from this seaweed would be done without pursuing this widely‐used industrial procedure.  相似文献   

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Bagarinao  T.  Lantin-Olaguer  I. 《Hydrobiologia》1998,382(1-3):137-150
Fish kills of milkfish Chanos chanos and tilapia Oreochromis spp. now occur frequently in brackish, marine, and freshwater farms (ponds, pens, and cages) in the Philippines. Aquafarms with high organic load, limited water exchange and circulation, no aeration, and high stocking and feeding rates can become oxygen-depleted and allow sulfide from the sediments to appear in the water column and poison free-swimming fish. The sulfide tolerance of 2–5 g milkfish and 5–8 g O. mossambicus was determined in 25-liter aquaria with flow-through sea water (100 ml min-1) at 26–30 °C and sulfide stock solutions pumped in at 1ml min-1. Total sulfide concentrations in the aquaria were measured by the methylene blue method and used in the regression against the probits of % survival. Four experiments showed that the two species have similar sulfide tolerance. In sea water of pH 8–8.5, about 163 ± 68 μM or 5.2 ± 2.2 mg l-1 total sulfide (mean ± 2 se) or 10 μM or 313 μg l-1 H2S was lethal to 50% of the fish in 4–8 h, and 61 ± 3 μM total sulfide or 4 μM H2S in 24–96 h (to convert all sulfide concentrations: 1 μM = 32 μg l-1). Earthen pond bottoms had 0–382 μM total dissolved sulfide (mean ± sd = 54 ± 79 μM, n = 76); a tenth of the samples had >200 μM. The water column may have such sulfide levels under hypoxic or anoxic conditions. To simulate some of the conditions during fish kills, 5–12 g milkfish were exposed to an abrupt increase in sulfide, alone or in combination with progressive respiratory hypoxia and decreasing pH. The tests were done in the same flow-through set-up but with sulfide pumped in at 25 ml min-1. The lethal concentration for 50% of the fish was 197 μM total sulfide or 12 μM H2S at 2 h, but 28–53 μM sulfide allowed fish to survive 6–10 h. Milkfish in aquaria with no aeration nor flow-through sea water died of respiratory hypoxia in 5–8 h when oxygen dropped from 6 to 1 mg l-1. Under respiratory hypoxia with 30–115 μM sulfide, the fish died in 2.5–4 h. Tests with low pH were done by pumping a weak sulfuric acid solution at 25 ml min-1 into aquaria with flow-through sea water such that the pH dropped from 8 to 4 in 5 h. Under these conditions, milkfish died in 7–9 h when the pH was 3.5. When 30–93 μM sulfide was pumped in with the acid, the fish died in 2–6 h when the pH was still 4.5–6.3. Thus, sulfide, hypoxia, and low pH are each toxic to milkfish at particular levels and aggravate each other's toxicity. Aquafarms must be well oxygenated to prevent sulfide toxicity and fish kills. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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浅论城市害蜂的危害与治理   总被引:6,自引:0,他引:6  
蜂害是我国城市化发展过程中出现的新问题。该文综述了国内外螫人害蜂的种类、习性与危害 ,蜂毒的成分与毒理 ,被蜂螫伤者的救治及蜂害的治理方法 ,分析了目前我国所面临的城市蜂害问题 ,并提出了应采取的相应对策  相似文献   

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上海地区草坪害虫的发生为害初步调查   总被引:3,自引:0,他引:3  
张平华  李跃忠 《昆虫知识》2003,40(6):519-522
据作者初步调查 ,2种草坪害虫 :稻切叶野螟Psaralicarsisalis (Walker)和灰翅夜蛾Spodopteramauritia (Boisduval)在上海均以幼虫在土下越冬 ,1年发生 5代 ,后期存在世代重叠现象。灰翅夜蛾虫口密度一直到 7月份都较低 ,8月份虫口密度上升很快 ,所以在上海地区第 3 ,4代幼虫为害最严重 ;稻切叶野螟的幼虫发生期比灰翅夜蛾迟 1 0d左右 ,以 9~ 1 0月份虫口密度最高。在矮生百幕达草坪中稻切叶野螟虫口密度明显高于灰翅夜蛾 ;而在高羊茅、黑麦草等草坪中灰翅夜蛾的虫口密度则远远高于稻切叶野螟。  相似文献   

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近年广西银杏病虫害发生及防治对策   总被引:4,自引:0,他引:4  
梁惠凌  唐辉  韦霄  李锋   《广西植物》2000,20(3):264-268
近年来 ,银杏病虫害在广西各栽培地区普遍发生。主要报导了在广西危害比较严重 ,造成较大经济损失的病虫害及其危害症状、形态特征、发生规律和防治措施。这些病虫害在广西多属首次发现报导。  相似文献   

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广东省菊花主要病虫害危害及其防治   总被引:4,自引:0,他引:4       下载免费PDF全文
介绍了广东省菊花主要病虫害的发生特点以及防治措施,为菊花病虫害的诊断提供参考。  相似文献   

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1990~1992年对射阳海涂芦苇的芦毒蛾、条锹额夜蛾、宫苍仁蚧以及芦苇褐斑病和芦苇叶锈病的主要生物学和生态学特点进行了观察研究,提出了以生态控制为基础的综合防治体系。防治实践表明,这一体系是可行的,具有良好的经济效益和生态效益。  相似文献   

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