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11.
Coprological examination of New Caledonian geckoes of the genus Rhacodactylus Fitzinger, 1843 revealed two new species of coccidia. Isospora leachiani sp. n. from R. leachianus (Cuvier, 1829) has oval, colourless oocysts, measuring 21-26 x 16-18.5 microm. Sporocysts are ellipsoidal, 11-12.5 x 6.5-8 microm, with distinct Stieda and substieda bodies. Oocysts of Isospora sykorai sp. n. from R. ciliatus (Guichenot, 1866) are elongately oval to cylindrical, 20-23.5 x 11-14 microm; sporocysts of this species are ellipsoidal, 10-11.5 x 7-8 microm, with a slightly pointed end and Stieda and substieda bodies. Infected geckoes did not exhibit any alteration of their health status.  相似文献   
12.
13.
The short-term effects of excessive NH4+-N on selected characteristics of soil unaffected (low annual N inputs) and affected (high annual N inputs) by cattle were investigated under laboratory conditions. The major hypothesis tested was that above a theoretical upper limit of NH4+ concentration, an excess of NH4+-N does not further increase NO3 formation rate in the soil, but only supports accumulation of NO2-N and gaseous losses of N as N2O. Soils were amended with 10 to 500 μg NH4+-N g−1 soil. In both soils, addition of NH4+-N increased production of NO3-N until some limit. This limit was higher in cattle-affected soil than in unaffected soil. Production of N2O increased in the whole range of amendments in both soils. At the highest level of NH4+-N addition, NO2-N accumulated in cattle-affected soil while NO3-N production decreased in cattle-unaffected soil. Despite being statistically significant, observed effects of high NH4+-N addition were relatively weak. Uptake of mineral N, stimulated by glucose amendment, decreased the mineral N content in both soils, but it also greatly increased production of N2O.  相似文献   
14.
This report presents an analysis of sexual abuse of five three-month old calves that died as a result of injury. A subsequent police investigation concluded that the animals had been sexually abused by an individual affected with zoophilia. The calves received injuries in the anogenital region resulting in fatal internal bleeding. The wounds appeared to have been caused by inserting and manipulating an unknown object into the vaginas of the animals. Post-mortem examination showed rupture of both the rectum and vagina in each calf with massive haemorrhage into the abdominal and thoracic cavities. From the psychiatric and animal welfare viewpoints animal sexual abuse is linked to clinical veterinary ethology. Ethical and legal aspects of animal welfare are evaluated with particular regard to the cases described.  相似文献   
15.
The fate of cadmium in field soils of the Danubian lowland   总被引:1,自引:0,他引:1  
The susceptibility of soils to deep penetration of cadmium was assessed by measuring cadmium adsorption on soil particles <0.01 mm, easily mobile in soil macropores, and bypassing ratio. The latter is defined as a ratio of the rate of macropore flow to the rate of total (macropore and matrix) flow. Measurements were made on soils from the Danubian lowland, which is a large (1260 km2) agriculturally managed area situated in the south-west of Slovakia, with a shallow (0.5–3.8 m deep) underlying aquifer containing about 10 km3 of freshwater. In this study, the susceptibility of soils to deep penetration of cadmium was assessed on light, loamy-sand soil in Kalinkovo, medium heavy, loamy soil in Macov, and heavy, clay soil in Jurova. It was found that when the interaction between soil and cadmium lasted 1 min, more than 35, 32, and 48% of cadmium was adsorbed on the particles <0.01 mm in soils from Kalinkovo, Macov, and Jurova, respectively. In the case of ponding infiltration, more than 50% of water can flow via topsoil macropores in Kalinkovo, about 70% in Macov, and 96% in Jurova. This value of bypassing ratio can be met during an irrigation/rain with higher intensity then the infiltration rate into the soil matrix of studied soils. As the rains resulting in the macropore flow can occur 24 times on average in south-western Slovakia during the vegetation season, the probability of deep penetration of cadmium is very high, mainly during an initial stage of rainfall. For this reason, some mitigative agricultural practices (e.g. subsurface fertilizer banding or shallow ploughing) should be used in this region to prevent soils from the deep penetration of cadmium.  相似文献   
16.
The effect of soil aeration status on carbon partitioning of a labelled organic substrate (14C-[U]-glucose) into CO2, microbial biomass, and extra-cellular metabolites is described. The soil was incubated in a continuous flow incubation apparatus under four different aeration conditions: (1) permanently aerobic, (2) permanently anaerobic, (3) shifted from anaerobic to aerobic, and (4) shifted from aerobic to anaerobic. The soil was pre-incubated for 10 days either under aerobic or under anaerobic conditions. Afterwards, glucose was added (315 g C g–1) and the soils were incubated for 72 h according to four treatments: aerobic or anaerobic conditions maintained, aerobic conditions shifted to anaerobic conditions and anaerobic conditions shifted to aerobic conditions. Carbon partitioning was measured 0, 8, 16, 24, 48 and 72 h after the glucose addition. In permanently aerobic conditions, the largest part of the consumed glucose was built into microbial biomass (72%), much less was mineralised to CO2 (27%), and only a negligible portion was transformed to soluble extra-cellular metabolites. Microbial metabolism was strongly inhibited when aeration conditions were changed from aerobic to anaerobic, with only about 35% of the added glucose consumed during the incubation. The consumed glucose was transformed proportionally to microbial biomass and CO2. In permanently anaerobic conditions, 42% of the consumed glucose was transformed into microbial biomass, 30% to CO2, and 28% to extra-cellular metabolites. After a shift of anaerobic to aerobic conditions, microbial metabolism was not suppressed and the consumed glucose was transformed mainly to microbial biomass (75%) and CO2 (23%). Concomitant mineralisation of soil organic carbon was always lower in anaerobic than in aerobic conditions.  相似文献   
17.
Summary Four groups of Czechoslovak land-races (Czech alternate, Czech red, Moravian white, awnless, South Moravian and Slovak awned wheats) are characterized on the base of wheat collection studies in the Research Institute for Crop Production, Praha-Ruzyn, and their use in the breeding in SSR. A review of Czechoslovak cultivars of winter and spring wheats registered in the years 1921–1980 (table 1 and 2) and the registration period of the most important older Czechoslovak cultivars (table 3) is presented.Of the total number of 284 registered Czechoslovak cultivars in the years 1921–1980 93 cultivars were developed by selection from land-races; 70% of 87 cultivars originated from crosses had a land-race or its derivative as one of its parents. From land-races derived cultivars Chlumecká 12, eská Pesívka, Slovenská 777, Dobrovická 10 displayed the longest duration in the registration.
Die Verwendung von Landsorten in der tschechoslowakischen Weizenzüchtung
Zusammenfassung Vier Gruppen von tschechoslowakischen Weizenlandsorten werden auf der Grundlage von Untersuchungen an der Weizenkollektion im Institut für Pflanzenproduktion, Prag-Ruzyn, und ihrer Nutzung in der Züchtung in der SSR beschrieben. Es sind (1) tschechische Wechselweizen, (2) tschechische rote, (3) mährische weiße, grannenlose und (4) südmährische und slowakische begrannte Weizen. Ein Überblick über die in den Jahren 1921–1980 registrierten tschechoslowakischen Winter- und Sommerweizen (Tab. 1 und 2) sowie die Zeitdauer der Registrierung der bedeutendsten älteren tschechoslowakischen Sorten (Tab. 3) schließt sich an.Von insgesamt 284 in den Jahren 1921–1980 registrierten tschechoslowakischen Sorten entstanden 93 durch Auslese aus Landsorten. Bei den 87 Sorten, die aus Kreuzungen hervorgingen, hatten 70% entweder eine Landsorte oder den Abkommen einer Landsorte unter den Eltern. Die aus Landsorten hervorgegangenen Sorten Chlumecká 12, eská Pesívka, Slovenská 777 und Dobrovická 10 waren am längsten registriert.

- : (1) , (2) , (3) , (4) . , 1921–1980 . (. 1 2), ( ) (. 3). 284 , 1921–1980 ., 93 ë . 87- , ë , 70% . ( ) : 12, , 777 10.


Paper not delivered during the symposium  相似文献   
18.
Overwintering cattle outdoors causes soil surface disturbance, substantial increases of soil Ntot, Corg, and P and a shift in pH to alkaline levels. Since fungi predominate in unfertilized soils with acidic pH and have filamentous hyphae, we hypothesized that changes caused by overwintering cattle outdoors (trampling, excreta returns, and changes in soil chemistry) will lead to suppressed species richness, lower biomass, and alter the structure of fungal communities. The research was conducted on an upland pasture used more than 10 years for cattle overwintering. Both culture-dependent and -independent methods were used for the determination of either fungal species composition (cultivation; DGGE) or biomass (numbers of CFU; concentration of fungal PLFA marker 18:2ω6,9). Soils under three different levels of cattle disturbance (S - severe, M - moderate, C - no disturbance/control) were investigated during three subsequent years. In addition, the DGGE analysis of soils was completed by comparison with analysis of fresh cattle excrements (Ex). The composition of fungal communities showed significantly higher richness and a substantial shift in species composition in cattle-disturbed soils (S, M) in comparison to the non-disturbed soil (C). The number of separated DGGE bands was significantly higher in S (30.67 ± 1.63; mean ± SD) and M (25.50 ± 1.64) soils than in the C soil (19.33 ± 1.75). Sequencing of typical bands revealed common fungal genera - Alternaria, Penicillium, Fusarium, Rhizopus, Isaria, and Metarhizium. Profiles of the S soil were enriched by bands of rumen-born anaerobic fungi (Neocallimastix, Cyllamyces) occurring mainly in profiles of excrements, where relatively low band richness (14.33 ± 1.15) was observed. The increasing level of cattle disturbance induced an increase in the biomass of complex fungal community over the three-year experimental period from 3.39 ± 2.11 (mean ± SD) nmol of fungal PLFA per gram of the C soil to 5.87 ± 3.16 in the M soil and 9.21 ± 4.69 in the S soil. Concentrations of soil Ntot and Corg were evaluated as the parameters significantly correlating with biomass as well as composition of the fungal community.  相似文献   
19.
The northern root-knot nematode (Meloidogyne hapla) is a prominent root vegetable pest in the Czech Republic. Effects of several plant essences for M. hapla management on carrot (Daucus carota) were tested. The tested compounds included commercially available plant essences from Ocimum basilicum (sweet basil), Mentha arvensis (field mint), Tagetes erecta (Mexican marigold), and commercial product of neem seed (Azadirachta indica). Two further essences from Eugenia caryophyllata (clove) and Origanum majorana (marjoram) were obtained by distillation. Tests were conducted on container-grown carrots maintained under field conditions. The delivery method involved absorbing the tested essences in perlite particles placed in a substrate. The results showed a negative correlation between gall numbers of the carrots and treatment concentrations, especially for clove and majoram. Similar results were achieved when considering M. hapla egg numbers. Furthermore, the same treatments showed significant differences (P ≥ 0.05) in fresh and dry root weights. Based on these results the management of M. hapla using plant essences seems to be possible, however, further research is desirable to determine the appropriate dosage needed for efficient and most appropriate delivery method of these substances under field conditions.  相似文献   
20.
Pasture soils used for cattle overwintering may represent significant sources of N2O emissions from soils. Therefore, the long-term effect of cattle overwintering on the abundance and activity of a denitrifying community was explored. The study was performed at a cattle overwintering area in South Bohemia (Czech Republic), where three sites differing in the degree of animal impact were selected: severely impacted (SI) and moderately impacted (MI), as well as a control site with no impact (NI). N2O flux measurement and soil sampling were performed in spring and fall of 2005. The activity was measured in terms of potential denitrification activity. Bacterial nirK, nirS and nosZ genes were used as functional markers of the denitrifying communities; abundance was analyzed using a real-time PCR assay. Surprisingly, in situ N2O emissions were the highest in spring at MI and significantly differed from those at SI and NI, while in autumn, rates of emissions generally decreased. In contrast potential denitrification rates were highest at SI, followed by MI, and the lowest at NI. An overall significant shift in N2O/N2 molar ratio was shown in cattle impacted sites. The highest abundance of all genes measured at both sampling times was found at site SI, whereas at site MI increased numbers were observed only in spring. Our results indicate a strong influence of cattle on the abundance as well as the activity of microbes involved in denitrification.  相似文献   
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