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1.
基于CLIMEX的桔小实蝇在中国适生区的预测   总被引:37,自引:2,他引:35       下载免费PDF全文
侯柏华  张润杰 《生态学报》2005,25(7):1570-1574
桔小实蝇Bactroceradorsalis(Hendel),属双翅目Diptera,果实蝇科Tetriphitidae,主要分布在热带和亚热带地区。温度和湿度是影响桔小实蝇分布的重要气候因子。根据桔小实蝇对温湿度等气候因子的反应,采用CLIMEX软件对桔小实蝇在中国大陆的适生区进行了预测。设置了CLIMEX中的相应参数17个:发育起点温度DV0、生长最适宜温度范围DV1~DV2、致死高温DV3、有效发育积温PDD。生长发育所需最低土壤湿度临界SM0、最适宜湿度范围SM1~SM2、最高土壤湿度临界SM3。冷胁迫日度临界DTCS及其积累速率DHCS,热胁迫临界温度TTHS及其积累速率THHS,干旱胁迫临界SMDS及其积累速率HDS,湿胁迫SMWS及其积累速率HWS。以印度和夏威夷为已知适生分布区,反复调试修正上述这些参数值,使之与已知广泛分布的地区达到最大程度的吻合。然后用优化后的参数和中国大陆85个气象站点的气象资料模拟桔小实蝇在中国大陆的适生分布,结果显示:广东、海南、香港、广西、四川、云南、湖南、湖北、福建、江西、浙江等11个省(区)是桔小实蝇的适生分布区。主要分布在我国的华南和西南大部分地区,以及华中和华东的部分地区。根据CLIMEX模拟结果的EI值大小,将桔小实蝇在我国大陆的适生分布情况进一步划分为最适宜、次适宜、适宜和非适宜4个气候区,即华南地区全部以及广西省全境是桔小实蝇的最适宜分布区,除桂林(EI=17)外,其余气象点的EI值均大于40;西南地区的四川、云南两省及福建沿海地区是桔小实蝇的次适宜分布区,平均EI值为29.7;适宜分布区包括湖南、湖北、江西、浙江的少数地区,除赣州(EI=17)外,其余点的EI值均小于10;长江以北的广大地区是桔小实蝇的非适宜区,这些地区不适合桔小实蝇生存。  相似文献
2.
14种虫草多糖对果蝇成虫寿命影响的试验   总被引:16,自引:0,他引:16  
采用从虫草深层发酵产物中提取的多糖进行果蝇抗衰老的试验表明,不同来源的虫草多糖对果蝇寿命均有不同程度的延长作用,从而证明虫草多糖有延缓衰老的作用;有的效果十分显著,来源于AT01的胞内、胞外多糖效果最好,延寿的效果随纯度的增大而提高。  相似文献
3.
Selection of Pupation Habitats by Oriental Fruit Fly Larvae in the Laboratory   总被引:15,自引:0,他引:15  
We performed a series of laboratory experiments to determine the effects of shade, soil moisture, and soil compaction on the selection of pupation habitats by wandering late-instar Oriental fruit flies, Bactrocera dorsalis (Hendel). Larvae showed a strong preference toward pupating in shaded rather than brightly lit areas, in moist rather than dry soil, and in soil with larger particle sizes. These behavioral preferences are likely to lead to clumped distribution of Oriental fruit fly pupae in natural habitats. The implications of this for management of localized populations by chemical and biological methods are discussed.  相似文献
4.
厦门地区桔小实蝇疫情监测   总被引:11,自引:2,他引:9  
1994年10月至1996年10月我们在厦门地区设置18个监测点,利用桔小实蝇性诱剂观测,结合室内外调查试验,基本查明本地区桔小实蝇的分布,为害情况及其消长规律。该虫在厦门普遍发生,为害15种果树植物,发生高峰期为8-10月份,影响发生的主要因子有温度和寄主等。  相似文献
5.
硫磺菌原变种液体培养代谢物生物活性分析   总被引:8,自引:0,他引:8       下载免费PDF全文
硫磺菌原变种Laetiporus sulphureusvar.sulphureus在液体培养条件下对果蝇具有致死效应,研究发现在液体培养过程中分泌到细胞外的代谢产物是致死效应的主要原因,并且上清液对果蝇的生物活性受pH值的影响。离子交换树脂柱和高效液相色谱分离分析表明草酸存在于硫磺菌原变种培养液的上清液中并且是果蝇致死效应和培养体系pH下降的一个重要因素。硫磺菌原变种在气升式反应器ALR/ff培养体系中草酸的浓度、菌丝体量和pH值呈简单相关。进一步分析发现还有另外一种结构未知、在碱性条件下呈紫红色的色素也具有致死效应。  相似文献
6.
A quantitative risk assessment is needed for each quarantine pest insect to ensure quarantine security without sacrificing the transparency of international trade. The probability of introduction, which is defined as the probability that one or more reproductive individuals of a pest insect species pass the port, is one of the basic components determining the risk of pest invasion. The probability depends on two biological characteristics of pests: mode of reproduction and spatial distribution of insects per host plant. In this article, the probability of introduction was calculated for each of the following four categories: (1) bisexual, gregarious pests; (2) bisexual, solitary pests; (3) parthenogenetic, gregarious pests; and (4) parthenogenetic, solitary pests. Then, equations were derived to predict the effects of two prevention practices conducted before export: disinfestation treatment and the subsequent export sampling inspection of consignments. These equations also enable estimation of the probability of introduction under natural mortality, which thus can be used in place of the criterion of Maximum Pest Limit (MPL). The method was applied to the Mexican fruit fly Anastrepha ludens (Loew), as an example. The contour graph of the probability of introduction indicated the optimal combination of the intensity of two prevention practices that ensures a given security level. Existence of an antagonistic interaction was also indicated between the disinfestation treatment and the subsequent sampling inspection. Received: January 22, 1999 / Accepted: September 6, 1999  相似文献
7.
陕西省常见四种实蝇的RAPD研究初报(双翅目:实蝇科)   总被引:6,自引:0,他引:6  
应用31种随机引物对陕西省常见4种实蝇的基因组DNA进行扩增,筛选出5种引物S61、S107、S126、S275、S1142,可以对4个种扩增出稳定清晰的多态性片段,其中引物S126可以把南瓜实蝇和具条实蝇,具条实蝇和三点棍腹实蝇分开;利用UPGMA法聚类构建的系统树与传统分类完全一致。  相似文献
8.
蘑菇菌丝体代谢产物对果蝇的致死效应   总被引:6,自引:0,他引:6  
以果蝇为靶标 ,对 15种蘑菇液体培养产物的毒性进行了检测 ,发现硫磺菌红色变种Laetiporussulphureusvar miniatus和硫磺菌原变种Laetiporussulphureusvar sulphureus液体培养中产生的代谢产物对果蝇具有致死活性。气升式生物反应器 (Airlift/ff)培养条件下 ,硫磺菌红色变种和原变种培养体系的 pH值均连续下降 ,最终都降至 2 2左右。研究发现致死活性产物被分泌到细胞外 ,离子交换树脂柱层析的线性洗脱分离结果表明活性代谢产物呈酸性 ,进一步分析表明草酸是活性代谢物之一 ,而树脂静止交换表明另外一种未知色素也具有致死活性  相似文献
9.
Male fruit flies learn to avoid interspecific courtship   总被引:5,自引:1,他引:4  
Dukas  Reuven 《Behavioral Ecology》2004,15(4):695-698
Experimental data suggest, and theoretical models typicallyassume, that males of many fruit flies (Drosophila spp) areat least partially indiscriminate while searching for mates,and that it is mostly the females who exert selective mate choice,which can lead to incipient speciation. Evidence on learningby male D. melanogaster in the context of courtship, however,raises the possibility that the initially indiscriminate malesbecome more selective with experience. I tested this possibilityby comparing the courtship behavior of male D. melanogasterexperienced at courting females of the closely related species,D. simulans, and inexperienced males. I found that comparedwith the inexperienced males, the males experienced with courtingD. simulans females showed significantly lower courtship towardfemale D. simulans. Both male treatments, however, showed virtuallyidentical courtship durations with female D. melanogaster. Theseresults indicate that male fruit flies adaptively refine theircourtship behavior with experience and suggest that the malescontribute more to assortative mating and incipient speciationthan is commonly assumed.  相似文献
10.
Population dynamics of Bactrocera dorsalis Hendel (Diptera: Tephritidae) were studied through pheromone trapping over 4 years (1997, 1999, 2000, 2003) in the Kunming region, a high plateau area in southwestern China. B. dorsalis immigrates from southern Yunnan to Kunming each year, and occurs during early May through November. Annual trap captures recorded an increase in the B. dorsalis populations from May to July, when they peaked in abundance, and a decline until November. No flies were detected from November to April. The fruit flies had two generations. There was considerable overlapping due to the continuous arrival of immigrating flies during the summer months. Annual capture rates were significantly related to numbers of flies caught in July when peak captures were recorded; whereas the peak captures, in turn, positively depended on numbers of flies recorded in May, the first month of fly appearance in the current year. It suggested that the annual population abundance was mainly dependent on the size of the initial emigrating population. A daily average temperature of 18℃ was probably the threshold temperature required for the flies to undertake long-range dispersal, which partially explained the start of the fly in May each year on this high plateau. Under field conditions, the fruit flies can withstand 13℃ as a daily average temperature. No flies were recorded in any of the study years at a daily temperature colder than 10 ℃.  相似文献
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