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‘Random‐flight’ dispersal in tropical fruit‐feeding butterflies? High mobility,long lifespans and no home ranges 下载免费PDF全文
NICHOLAS C. MARCHANT ARI PURWANTO FRANSISKUS A. HARSANTO NICHOLAS S. BOYD MARK E. HARRISON PETER R. HOULIHAN 《Ecological Entomology》2015,40(6):696-706
1. Tropical fruit‐feeding Nymphalidae butterflies are widely used in research, monitoring, and conservation projects, but to date a key aspect of their behaviour – dispersal – remains poorly understood. They have anecdotally been described as ‘relatively sedentary’ based on movement vectors from mark‐recapture studies, but this may be inaccurate because plot‐based studies in small sampling areas often underrepresent long‐distance movements. 2. Based on data from a peat‐swamp forest in Borneo, it was found that these butterflies may be much more mobile than previously thought, as they frequently moved distances of 1–2 km between sampling plots. Median daily movements were approximately 200–250 m, and over lifespans of one or more months these movements may sum to total life‐time dispersals of several kilometres. 3. Recapture rates for long‐distance movements between sampling plots were between 28.2% and 41.6% of the re‐encounter rates that would be predicted by a random‐walk approximation/Brownian motion (without accounting for survival rates), supporting the hypothesis that it is a suitable model of dispersal in this group, although further research is needed to confirm this. 4. There was no evidence that butterflies occupied permanent home ranges, and it is suggested that a permanent home range or territorial behaviour would be maladaptive in this group. Pseudo‐replication caused by ‘trap‐happy’ behaviour was not found to be widespread, and some recommendations are provided regarding the treatment of recapture data in trap‐based studies. 5. These findings substantially increase the spatial parameters for future research and conservation projects in this group and are also applicable to theoretical modelling studies. An abstract for this article in Bahasa Indonesia is included in the online supporting information File S1. 相似文献
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A. E. W. BOYD 《The Annals of applied biology》1952,39(3):351-357
A laboratory method is described in which a modified hypodermic syringe is used to inoculate potato tubers with Fusarium caeruleum. This injection method gives consistent results and permits reliable assessments of factors such as varietal susceptibility.
The occurrence of arrested lesions is noted.
Suspensions of very high spore concentration or of spores already germinated did not greatly increase the amount of dry rot above that given by the standard too spores per inoculation, provided that spore germination was adequate.
The size of tuber and site of inoculation were found to have a considerable effect upon the results of inoculation experiments, large tubers being more susceptible than small ones and the heel end being more susceptible than the rose end. The necessity for uniformity of material used in inoculation experiments is emphasized. 相似文献
The occurrence of arrested lesions is noted.
Suspensions of very high spore concentration or of spores already germinated did not greatly increase the amount of dry rot above that given by the standard too spores per inoculation, provided that spore germination was adequate.
The size of tuber and site of inoculation were found to have a considerable effect upon the results of inoculation experiments, large tubers being more susceptible than small ones and the heel end being more susceptible than the rose end. The necessity for uniformity of material used in inoculation experiments is emphasized. 相似文献
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Chlorophyll a content in segments of flag leaves from 19 wheatvarieties excised at ear emergence was shown to vary by a factorof 2.3. Chlorophyll stability (expressed as the percentage ofchlorophyll remaining in the segments after 4 days senescencein moist boxes at 20 °C in the dark) varied by a factorof 8.5. Variation in these parameters between varieties appearedto be independent. Five of these varieties, representing the extremes, were furthertested at three nutrient levels, and under three light/temperatureregimes. Whilst lower leaf canopy senescence was greater atlow nutrient levels, flag leaf chlorophyll content actuallyincreased slightly, stability remaining fairly constant. Incontrast, as light intensity improved, chlorophyll content increasedmarkedly, with a consequent slight non-significant decreasein stability. Testing the F1 progeny of a partial diallel involving four ofthe above varieties showed that the mean chlorophyll content,and stability, of the parents followed the same ranking as theprogeny to which they contributed. This suggests heritable controlof the parameters measured. Some implications of these resultsin breeding for resistance to senescence are discussed. 相似文献
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I. L. BOYD 《Mammal Review》1986,16(3-4):125-130