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141.
We investigated the possible relationship between the agricultural use of insecticides and the emergence of insecticide resistance. Bioassays were conducted using simulated mosquito larval habitats and well known Anopheles gambiae strains. Soil samples were collected from vegetable production areas in Benin, including one site with insecticide use, one site where insecticides had not been used for two months, and a third where insecticides had not been used. Pupation and emergence rates were very low in pyrethroid‐susceptible strains when exposed to soil that had been recently exposed to insecticides. Pupation and emergence rates in strains with the kdr mutation alone or both the kdr and Ace‐1 mutations were much higher. Overall, strains with the kdr mutation survived at higher rates compared to that without kdr mutation. Although this study is observational, we provide indirect evidence indicating that soils from agricultural areas contain insecticide residues that can play a role in the emergence of insecticide resistance in Anopheles. This aspect should be taken into account to better utilize the insecticide in the context of integrated pest management programs.  相似文献   
142.
马科在中国的分布与现状   总被引:21,自引:5,他引:16  
高行宜  谷景和 《兽类学报》1989,9(4):269-274
蒙古野驴(Asinus h.hemionus)分布于内蒙和甘肃西北角、新疆东北部至准噶尔盆地西部。1982年航调,卡拉麦里山保护区内有356头,O.02头/平方公里;1986年调查为O.03头/平方公里。估计目前我国境内不超过2000头。西藏野驴(Asinus k.kiang)分布于西藏西部、新疆南缘山地;A.k.holdereri分布于除湟水河谷外青海全境、四川西北角、甘肃祁连山。1984年调查,阿尔金山保护区内有41,262头,0.917头/平方公里。估计我国境内种群约在20万头上。多年考察未发现野马(Equus przewalskii),目前可能在北塔山以东尚有少数残存。  相似文献   
143.
The isozymes of superoxide dismutase (SOD) in leaves of wheat and peanut were investigated and identified by isoelectric focusing gel electrophoresis. The total four bands were found in wheat leaves, among them the band with the highest mobility was proved to be the chloroplastic SOD, the others with intermediate mobilities were probably cytoplasmic SODs. It was observed that there was apparent difference between patterns of SOD isozymes from leaves of wild and cultivated peanut. Leaves of wild peanut contain three different types of SOD isozyme (band A, band B and band C). Band A and B were cyanide-sensitive, hence they should be Cu-Zn-SOD. Band C was cyanide- insensitive and might be Mn-SOD located in mitochondria. The major part of SOD activity in cultivated peanut leaves was concentrated in chloroplasts, and it was cyanide-sensitive. The experiments of SOD activity inhibition by KCN showed that leaves of cultivated peanut contained more Cu-Zn-SOD. On the contrary, the percentage of non-Cu-Zn-SOD was highter in wild species than in cultivated. The PI values of distinct bands were determined and the significance of this study for the further evaluation of resistance of peanut plant is discussed.  相似文献   
144.
Paeonia suffruticosa Andrews subsp. spontanea (Rehder) S. G. Haw et L. A. Lauener ( =P. spontanea = P. jishanensis) has been considered as the wild form of widely cultivated P. suffruticosa. However, the subspecies differs from the cultivated one in shape, division and indumentum of leaves and reproductive biology. As a result of extensive field work, a form with two individuals in Yinping Shan, Caohu, Anhui, and Songxian, Henan, are found to be extremely similar to P. suffruticosa, but apparently different from P. jishanensis. The form is considered to be the wild one of P. suffruticosa and described as new: P. suffruticosa subsp, yinpingmudan Hong, K. Y. Pan et Z. W. Xie.  相似文献   
145.
野生朱鹮的种群数量和分布现状   总被引:2,自引:0,他引:2  
2012年9-10月,我们对野生朱鹮(Nipponia nippon)的分布区和潜在分布区进行了调查,共发现其游荡期夜宿地23个,其中20个有朱鹮夜宿,分布在洋县(16个)、宁陕县(3个)和城固县(1个)。对这些夜宿地进行了的同步调查,共统计到野生朱鹮1 090只,其中97.2%分布在洋县境内。最大的夜宿集群数量为184只,集群数量超过40只的夜宿地共11个,累计停歇的朱鹮占总数的91.7%,表明野生朱鹮在游荡期有趋于集结较大群体夜宿的习性。朱鹮野生种群中当年出生的幼鸟占19.0%,据此估算,截至秋季朱鹮幼鸟的存活率约为67.2%。加强对保护区以外,尤其是野生朱鹮新扩散地区的的保护管理,将促进野生朱鹮种群的扩散,进一步增加这一濒危物种抵御风险的能力。  相似文献   
146.
Biological characteristics of western flower thrips, Frankliniella occidentalis (Pergande) (Thysan., Thripae), were investigated on excised leaves of five vegetables: cabbage (Brassica oleracea L. var. Jingfeng 1), cucumber (Cucumis sativus L. var. Zhongnong 8), capsicum (Capsicum annuum L. var. Zhongjiao 5), kidney bean (Phaseolus vulgaris L. var. Gonggeizhe) and tomato (Lycopersicon esculentum M. var. zhongza 9). The developmental time from egg to adult on the cucumber, cabbage, bean, capsicum and tomato leaf was 9.22 ± 0.13, 10.19 ± 0.08, 10.42 ± 0.06, 12.15 ± 0.07 and 12.91 ± 0.04 days, respectively. Survivorship of immatures on cucumber, cabbage and tomato was high (75–80%) but low on capsicum (50%). The total number of first instars produced was highest on cabbage (76.62 ± 11.79), while the daily first instar production was highest on cucumber (6.12 ± 1.81), whereas the total and daily first instar production rates were lowest on capsicum (7.67 ± 3.35 and 1.89 ± 0.91). F. occidentalis had the highest intrinsic rate of increase (rm) on cucumber (0.208), followed by cabbage (0.184), bean (0.164), tomato (0.100) and capsicum (0.017). The results indicate that cucumber was the most suitable host plant for F. occidentalis, whereas capsicum was the least suitable.  相似文献   
147.
高氧对果蔬采后生理影响研究进展   总被引:4,自引:0,他引:4  
高氧(21%-100%O2)贮藏是近几年发展起来的果蔬采后处理技术之一.概述了高氧对果蔬采后生理如呼吸作用、乙烯合成、组织褐变、活性氧代谢及抗氧化能力、风味等方面的影响,还介绍了高氧对病原微生物生长和采后果蔬腐烂控制的作用.  相似文献   
148.
动物肠道菌群与宿主在营养代谢、免疫、疾病等方面有密切的关系。鉴于肠道菌群的这种重要性,野生动物肠道菌群宏基因组学日益成为保护生物学的研究热点。本文主要综述了近年来野生哺乳动物肠道微生物组的若干最新研究进展,着眼于宿主食性适应、健康、宿主与微生物组的协同进化等若干重要问题,对食肉类、灵长类、有蹄类、有袋类、鲸类、啮齿类等几大比较受关注的动物类群分别进行了总结,以期为今后我国哺乳动物肠道微生物组的研究提供一些视角和方向,并为野生动物的保护提供新的理论基础及研究手段。  相似文献   
149.
Korea is considered one of the centers of genetic diversity for cultivated as well as wild soybeans. Natural habitats of wild soybeans are distributed across the Korean mainland and the islands surrounding the Korean peninsula. In this study, the genetic diversity of 100 mainland Korean wild soybean accessions was evaluated by using 42 simple sequence repeat markers covering 17 soybean chromosomes. All analyzed loci were polymorphic and a total of 114 alleles were found. The observed average genetic diversity was low (0.4). The results showed that the 100 selected accessions did not exactly follow the geographical distribution. These results were further confirmed by the phylogeny inferred from five morphological characteristics (i.e., leaf shape, leaf area, plant shape, seed area, and 100-seed weight). Together, the genetic and morphological evaluations suggested conclusively that the selected population did not follow the geographical distribution pattern. The present study could provide useful information for the ex situ conservation and exploitation of wild soybean accessions in soybean improvement stratagems, and will aid in further understanding about the phylogeography of the species in the Korean center of diversity.  相似文献   
150.
Essential oils (EOs) from Eucalyptus globulus Labill . ssp. globulus and from Mediterranean autochthonous aromatic plants – Thymus mastichina L., Mentha pulegium L., Rosmarinus officinalis L., Calamintha nepeta (L.) Savi ssp. nepeta, Cistus ladanifer L., Foeniculum vulgare L., Dittrichia viscosa (L.) Greuter ssp. viscosa – were extracted by hydrodistillation and characterized by GC‐FID and NMR spectroscopy. EOs were evaluated for antimicrobial properties against several bacterial strains, using diverse methods, namely, the agar disc‐diffusion method, the microdilution method, the crystal violet assay and the Live/Dead staining for assessment of biofilm formation. Potential synergy was assessed by a checkerboard method. EOs of R. officinalis and C. ladanifer showed a predominance in monoterpene hydrocarbons (> 60%); EOs of C. nepeta, M. pulegium, T. mastichina, E. globulus and F. vulgare were rich in oxygenated monoterpenes (62 – 96%) whereas EO of D. viscosa was mainly composed of oxygenated sesquiterpenes (54%). All EOs showed antimicrobial activity; M. pulegium and E. globulus generally had the strongest antimicrobial activity. EO of C. nepeta was the most promising in hampering the biofilm formation. The combinations D. viscosa/C. nepeta and E. globulus/T. mastichina were synergistic against Staphylococcus aureus. These results support the notion that EOs from the aromatic plants herein reported should be further explored as potential pharmaceuticals and/or food preservatives.  相似文献   
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