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21.
Based on the observation that the root disease caused by P. cinnamomi on Q. ilex has a low incidence and severity in soils with medium-high Ca2+ content, we studied the ability of Ca2+ fertilizers to induce soil suppressiveness to the pathogen. Studies on cultures of P. cinnamomi exposed to different Ca2+ fertilizers in vitro showed significant inhibition of sporangial, chlamydospore and zoospore production at millimolar concentrations while mycelial growth was mainly unaffected. Experiments performed with artificially infested soil showed that some Ca2+ fertilizers induce a significant decrease on chlamydospore viability. Additionally, greenhouse experiments using artificially infested soils showed a significant reduction of foliar and root symptom severities in Holm oak seedlings growing in soils amended with Ca2+ fertilizers. We suggest that limestone amendments in oak rangelands could enhance the suppressiveness of soils to P. cinnamomi, and it is likely that the inhibition of sporangial production was the main mechanism involved.  相似文献   
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Outputs from the HadCM3 Global Climate Circulation Model according to scenarios A2 and B1 were used for climate change predictions in Lithuania. According to scenario A2, the annual temperature will increase by approximately 4.0 °C from 2061 to 2090, while scenario B1 predicts an increase of 2.0 °C. In contrast to scenario B1, scenario A2 predicts an annual increase in precipitation of 15–20 % at the end of the century. Based on the predicted climatic data for the two scenarios and climate maps by European Food Safety Authority for the EU, we created climate analogues for Lithuania for 2031–2060 and 2061–2090. These areas were overlain by the digital map of native tree species distributions in Europe, which was created from the European Forest Genetic Resources Programme database. If climate changes occur according to scenario B1, in 2031–2060, Lithuania’s climate will become suitable for approximately five to six alien species, such as Acer campestre, Acer pseudoplatanus, Fagus sylvatica, Populus nigra, and Prunus avium. In 2061–2090, these species will be joined by Sorbus domestica and Tilia platyphyllos. If climate changes occur according to scenario A2, at the end of the twenty-first century, Castanea sativa, Quercus pubescens, and Sorbus torminalis could expand this list. With respect to species dispersal rates, there is a high probability that the species A. campestre, A. pseudoplatanus, P. nigra, and P. avium will become immigrants to Lithuanian forests at the end of the twenty-first century. Approximately 20 new species native to Europe will be suitable for cultivation (scenario A2). Climate change will affect the distributions of native species too. An increase in the proportion of deciduous tree species (except Alnus incana) and some reduction in the proportion of conifers, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), are expected in Lithuanian forests.  相似文献   
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The early post-fire development of mycobiota following a crown fire in mountain pine plantations and a surface fire in Scots pine plantations, and in the corresponding unburnt stands in the coastal sand dunes of the Curonian Spit in western Lithuania was investigated. Species numbers in unburnt Pinus mugo and Pinus sylvestris stands showed annual fluctuation, but in the burnt sites, the numbers of fungi increased yearly, especially in the crown fire plots. Both burnt stand types—P. mugo and P. sylvestris—showed strongly significant (two-way ANOSIM; R = 1, p < 0.05) differences in species composition; the differences between unburnt sites were clearly expressed but less significant (R = 0.86, p < 0.05). Fungal species composition of burnt P. mugo and P. sylvestris sites was qualitatively different from that of corresponding unburnt sites (two-way ANOSIM; R ≥ 0.75, p < 0.05). The chronosequence of mycobiota in surface fire burns was less clearly defined than in crown fire sites, reflecting the greater patchiness of impacts of the surface fire. Although both fire types were detrimental or at least damaging to all functional groups of fungi (saprobic on soil and forest litter, wood-inhabiting, biotrophic, and mycorrhizal and lichenized fungi), their recovery and appearance (fructification) patterns varied between the groups and among the burn types. The end of the early post-fire fungal succession (cessation of sporocarp production of pyrophilous fungi) was recorded 3 years after the fire for both crown and surface fire types, which is earlier than reported by other authors. Rare or threatened fungal species that are dependent on fire regime were not recorded during the study.  相似文献   
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Phytophthora cinnamomi is a soilborne pathogen causing root rot in Mediterranean Quercus species growing in ‘dehesa’ rangeland ecosystems. Recently, it has been reported causing wilting and death of Lupinus luteus (yellow lupin), a spontaneous plant in southern Spain rangelands, but also frequently sowed for livestock grazing. In soils artificially infested with P. cinnamomi chlamydospores and planted with different cultivars of yellow lupin, a significant increase in the density of propagules was detected in comparison with the initial levels of inoculum and with the infested but not planted soil (control). In oak‐rangelands in which yellow lupine was planted, isolation and counting of colonies of P. cinnamomi from soil samples have shown the ability of this plant to maintain or even increase the inoculum density and thus facilitate the infection of trees. Results suggested that cultivation of yellow lupin in oak‐rangeland ecosystems should be avoided whether oak trees are affected by root disease caused by P. cinnamomi or not. This leguminous plant can act as an inoculum reservoir or even enhance inoculum soil levels available for oak root infections, exacerbating the oak decline severity in the region.  相似文献   
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Vincenzetti  S.  Polidori  P.  Salimei  E.  Mariani  P. L.  Allegri  S.  Cammertoni  N.  Quadrini  B.  Vita  A. 《Veterinary research communications》2015,29(2):211-213
Veterinary Research Communications -  相似文献   
29.
The paper presents information concerning metrological and technical characteristics of KTU-Griff-Tester device, the optimization of its parameters and the cases of its application. It was defined that the behaviour of textile material during its extraction through a rounded hole depends upon its structure. Variations of geometrical shape of woven and knitted specimens can be described by mathematical expressions of shortened epicycloids and Cassini ovals. It is shown that waving process of disc shaped specimen can be predicted on the basis of the law of sine curve. The examples of textiles treatment with different types of commercial softeners are presented, herewith showing the suitability (sensitiveness) of the new device to detect the changes of textile hand. Meantime it is shown that the level of materials anisotropy can be decided on the basis of transformations of specimen’s geometrical shape.  相似文献   
30.
Searching for novel energy crops, an interest in C4-type plant switchgrass (SWG) has increased worldwide. The present research was aimed to study SWG genetic resources for most important agrobiological traits with a view of extending the range of energy plants in the Nemoral zone of Europe. SWG was studied for the peculiarities of developmental stages, winter hardiness, and dry matter (DM) yield. SWG regrowth in spring started one month later compared to the reed canary grass (variety ‘Chiefton’). All investigated genotypes matured seeds in the second half of September. The most winter-hardy SWG accessions (0–20% winter damage) were the majority of wild ecotypes and the variety ‘Dacotah’ from North Dakota (2–4 hardiness zone) as well as the variety ‘Summer’ from South Nebraska (4, 5 hardiness zone). Ecotypes from North Dakota exhibited a high breeding potential and prospects in Northern regions of Europe due to genotypic variation of winter hardiness trait. The varieties ‘Alamo’, ‘Falcon’, ‘Grenville’, ‘Shawnee’, and ‘Trailblazer’ that originated from warmer climate zones (6–9 hardiness zone) were heavily damaged or completely killed. The worst overwinter survival of plants was recorded after the first winter. DM yield was estimated at two regimens of cutting. When grass was cut once at seed maturity stage, DM yield in the first harvest year was 249 g per plant, in the second harvest year 349 g per plant, and in the third harvest year 493 g per plant. When grass was cut twice per season (at the beginning of anthesis and after regrowth of aftermath), DM yield was significantly lower: in the first harvest year the DM yield was 203 g per plant (18.4% less), in the second harvest year 182 g per plant (47.9% less), and in the third harvest year 272 g per plant (44.7% less).  相似文献   
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