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51.
In 1993 we observed the sensitivity of wheat powdery mildew populations (Erysiphe graminis DC f.sp. tritici Marchal) from the Czech Republic, Austria, Hungary and Slovakia to the fungicides triadimenol, tebuconazole, propiconazole, flutriafol and fenpropimorph. The highest resistance value was shown to triadimenol, which attained a mean resistance factor (MRF) of 29 (expressing how many times the population is more resistant than are standard sensitive isolates) in the mildew population from the Czech Republic. The mildew populations from eastern Slovakia and eastern Hungary, populations geographically isolated from the other populations, showed very high sensitivity to all fungicides tested. There was most sensitivity to fenpropimorph (smallest MRF values) compared with the other fungicides. Cross-resistance was established among all triazoles used, but not between triazoles and fenpropimorph. Sensitivity of wheat powdery mildew populations from Central Europe to these fungicides is considered adequate, and the development of resistance has shown a decreasing tendency in recent years.  相似文献   
52.
Pig chromosome 7 (SSC 7) has been shown to be rich in QTL affecting performance and quality traits. Most studies mapped the QTL close to the swine leukocyte antigens (SLA), which has a large effect on adaptability and natural selection. Previous comparative mapping studies suggested that the 15-cM region limited by markers LRA1 (mapped at 55 cM) and S0102 (mapped at 70 cM) contains hundreds of genes. To decrease the number of candidate genes, we improved the mapping resolution with a genetic chromosome dissection through a backcross recombinant progeny test program between Meishan (MS) and European (EU; i.e., Large White or Landrace) breeds. Three first-generation backcross--(EU x MS) x EU--and two second-generation backcross--([EU x MS] x EU) x EU--sires carrying a recombination in the QTL mapping interval were progeny-tested (i.e., measured for a total of 44 growth, fatness, carcass and meat quality traits). Progeny family size varied from 29 to 119 pigs. Animals were genotyped for markers covering the region of interest. Progeny-test results allowed the QTL interval to be decreased from 15 to 20 cM down to 10 cM, and even less than 6 cM if we assumed that the EU pigs used in this study share only one QTL allele. Except for a putative QTL affecting some carcass composition traits, the SLA is excluded as a candidate region, suggesting that it might be possible to apply a marker-assisted selection strategy for this QTL, while controlling SLA allele diversity. The strong QTL effects remaining in animals with only 12.5% (issued from first-generation backcross boars) and 6.25% (issued from second-generation back-cross boars) Meishan genetic background shows that epistatic interactions are likely to be limited. Finally, the QTL does not have strong effects on meat quality traits.  相似文献   
53.
Lufenuron, a benzoylphenyl urea derivative, was evaluated as a treatment for endometrial fungal infections in 4 mares. Intrauterine lavage was performed with lufenuron suspended in sterile saline (0.9% NaCl) solution. Cytologic evaluation and fungal culture of the endometrium, as well as subsequent reproductive performance, were used to monitor efficacy of this treatment. Fungal endometritis in mares is associated with infertility. Treatment is often ineffective and costly, and recurrence following treatment is not uncommon. Intrauterine infusions of lufenuron were effective in eliminating fungal endometritis in the 4 mares of this report.  相似文献   
54.
Journal of Plant Diseases and Protection - Didymella applanata, the causal agent of raspberry spur blight, is a destructive plant pathogen that can cause serious reductions in total yield. The use...  相似文献   
55.
Journal of Plant Diseases and Protection - During a survey from 2004 to 2016, symptoms of grapevine dieback were observed in six vineyards in Serbia. Symptoms initially appeared as small,...  相似文献   
56.
Plant Foods for Human Nutrition - Two environmentally friendly innovative extraction techniques - subcritical water (SWE) and microwave-assisted extraction (MAE) were applied for the extraction of...  相似文献   
57.
The Cittadella di Alessandria (Italy) is a military fortification that was built in the 18th century. The site has recently been abandoned and is now colonised by weeds, including the invasive Ailanthus altissima. The aim of the study was to compare the efficacy of different herbicides (glyphosate, a mixture of aminopyralid + fluroxypyr and triclopyr + fluroxypyr) applied to cut stumps or to the basal bark of A. altissima. For the cut stump application, plants were first cut at the base and then immediately sprayed and for the basal bark application, the lower 50 cm of the plants was sprayed with the herbicides; untreated cut plants were used as a control, for comparison. Two runs per study were carried out (in summer 2015 and in spring 2016). Efficacy was assessed up to 2018 by counting the resprouts and their height in the cut stump application and, for the basal bark treatment, by measuring the variation in the plant circumference after treatment. The cut stump treatment carried out in summer greatly reduced the number of resprouts, compared to the spring treatment, to less than one sprout per plant when aminopyralid + fluroxypyr was used, and its efficacy lasted for about two years. The basal bark treatment did not control the species, but lower levels of variation in circumference and greater mortality were detected in plants treated with aminopyralid + fluroxypyr. Considering the high level of infestation of the site and the high risk of plant resprouting, repeated cut stump treatments with aminopyralid + fluroxypyr would be preferable to eradicate this invasive species.  相似文献   
58.
Three new species of chigger mites, Eutrombicula cubensis sp. n. and E. anguliscuta sp. n. from lizards and bats, and E. leiocephali sp. n. from lizards, are described. One species, E. lipovskyana (Wolfenbarger, 1953), is recorded for the first time in Cuba. Data on distribution of E. alfreddugesi (Oudemans, 1910) in Cuba are reported.  相似文献   
59.
Phenotypic plasticity is an important mechanism to maximise fitness in unpredictable environments by fine‐tuning phenotypes to a specific environmental setting. We used Nothobranchius furzeri, an African annual fish from temporary pools with erratic changes in habitat condition, to study changes in the allocation to growth and reproduction and to test the key trade‐off between egg size and number. In an experimental setting, we quantitatively varied ration at two levels and over two time periods, including temporal switches in ration level. As predicted, female N. furzeri possessed the capacity for compensatory growth, which surprisingly came with no longer‐term cost to fecundity. Females responded strongly to ration manipulation, with a pronounced decrease in fecundity associated with a low ration, even after accounting for body mass. Due to the unpredictability of offspring environment, we expected no adaptive change in oocyte size. However, females responded to the quality of their environment in accordance with an adaptive maternal effect, with females receiving a low ration producing larger eggs. Further, a switch in ration size in either direction was associated with a decrease in egg size. There was a trade‐off between egg size and number in half of the treatments, but high variability in egg size among females made the relationship complex. Overall, N. furzeri females demonstrated high plasticity in both growth rate and fecundity parameters. Females appear able to track and respond adaptively to unpredictable changes in food availability in their environment.  相似文献   
60.
Although many reforestation projects have attempted to mitigate deforestation in the Philippines, most have focused on planting introduced trees, often with low success rates. A smallholder-based project in the Visayas region planted native species instead. This study assessed the growth performance of forty-four native and sixteen introduced species in 25 sites established by this project between 1995 and 2000. Diameter at breast height and total height were measured for 2,789 trees. Mean annual increments for diameter (MAID) at breast height and height (MAIH) were significantly higher for trees planted on limestone-influenced soils (MAID = 1.19 cm/year; MAIH = 1.05 m/year) than on purely volcanic soils (MAID = 0.81 cm/year; MAIH = 0.78 m/year). Growth of two native species, Melia dubia and Terminalia microcarpa, was higher than that of the widely planted exotic Swietenia macrophylla. The height increment for the highest-performing dipterocarp species, Shorea guiso, Shorea contorta, and Parashorea malaanonan, was not statistically different from the MAIH of S. macrophylla. A range of soil characteristics predicted performance, with organic matter predicting growth for six species, and percent nitrogen and percent clay predicting performance of five species. These findings show that certain native species can perform better than some exotic species when planted in open areas. They also disprove the widely held belief in the Philippines that Dipterocarpaceae cannot be planted in grasslands, and suggest that dipterocarps can be used successfully in reforestation. Finally, the findings show that more research is needed on species-site matching and on silvicultural management of native species plantations.  相似文献   
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