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71.
The article is an attempt to summarize available information about the relationships within Dasypyrum (Triticeae, Poaceae) and between Dasypyrum and other genera in the Triticeae. A relationship between the annual diploid D. villosum (L.) P. Candargy and the perennial tetraploid D. breviaristatum (L.) Frederiksen is discussed on the basis of cytological and molecular investigations. Although the relationship between the two Dasypyrum species seems to be quite close, D. breviaristatum is an autotetraploid with a basic genome different from that of D. villosum. The position of Dasypyrum in relation to other Triticeae is summarized, with special attention being paid to the Triticum and Secale. The closer relationship of Dasypyrum with Secale in comparison to Triticum seems to be reliable, even if only few intergeneric hybrids have been produced. It may be related to the fact that only a few experiments on production of those hybrids have been conducted till the present day, in contrast to experiments concerning hybrids with Triticum.  相似文献   
72.
ABSTRACT

The aim of the study was to determine the long-term effect of legumes as forecrops on the productivity of rotation with nitrogen fertilisation. The rotation included: legumes + spring barley, winter triticale and winter rape. The study was conducted as a two-factorial field experiment with four replications. The present study showed that legumes, as forecrops, increased the yield of WT cultivated in the second year of rotation. The seed yield of WR cultivated in the third year of rotation significantly increased after all legume forecrops, with the exception of PEA. Yielding of these crops depended also on nitrogen fertilisation. In the case of WT doses 120 kg N ha?1 and 180 kg N ha?1 there was an increased yield compared with control independent of forecrop, but there were no significant differences between doses 120 and 180 kg N ha?1. The conclusion is that we do not need to use dose 180 kg N ha?1 for WT cultivated directly after legumes. In the cultivation of WR in the third year of rotation there is no need to use a dose of nitrogen 180 kg N ha?1 if the fore-fore-crops were indeterminate cultivars of BL or YL.  相似文献   
73.
ABSTRACT

Climate change brings increasing attention to winter sowing of traditionally spring sown crops. Crop stand height, soil coverage, grain yield and yield components of six winter pea varieties and one spring pea variety were compared in eastern Austrian growing conditions in 2014 and 2015. Crop stands of winter pea were taller up to the end of May before they declined and crop stands of spring pea were taller from early June on. Winter pea covered the soil at least partly over winter and showed faster soil coverage in spring. At the end of May, just some weeks before harvest, spring pea attained equal soil coverage. Grain yield of winter pea was almost double that of spring pea due to higher pod density whereas spring pea produced more grains pod?1 than four out of six winter pea varieties and a higher thousand grain weight than all winter pea varieties. Consequently, grain density was higher for winter pea while the single pod yield was higher for spring pea. Growing winter peas in Central Europe might be a good strategy for increasing grain legume productivity and thereby European feed protein production.  相似文献   
74.
The effects of adding amino acids on the content of acrylamide in potato crisps, French fries, flat breads, and bread crusts were investigated. Addition of glycine or glutamine during blanching of crisps reduced the amount of acrylamide by approximately 30% compared to no addition. No effect was found in French fries. Addition of glycine during doughmaking significantly reduced acrylamide in both flat breads and bread crusts. In bread crusts the reduction of acrylamide ranged from 50 to >90% depending on the baking condition. In flat breads the reduction varied between 60 and >95%.  相似文献   
75.
ABSTRACT

In experiments with weed harrowing crops are negatively affected by competing weeds but also by the destructive effect of used implement. This research was carried out to find growth stages during which mixture of oat (Avena sativa L.) and triticale (× Triticosecale Wittm.) was resistant to harrowing and was able to effectively recover from this physical disturbance. Plots were harrowed 1–3 times on the same day at six consecutive stages of mixture growth with spring-tine harrow. After the latest harrowing, all plots were sprayed with herbicide to exclude competitive effect of weeds on the mixture. Compared to non-harrowed plots plant density of mixture was significantly reduced after a single cultivation at 1- and 2-leaf stage (20% and 23% respectively), two cultivations at 3-leaf stage (22%) and three at the beginning of the tillering (21%). No yield penalty was noticed for the density reductions, thus showing high ability of mixture to recover from physical disturbance. We recommend plant emergence as an appropriate growth stage for single harrowing of oat-triticale mixture. Two cultivations on the same day should not be planned earlier than at the beginning of tillering.  相似文献   
76.
-  Arsenic is a toxic metalloid element that is now recognised to be an important contaminant of drinking water – particularly, but not exclusively, in poor regions of southern Asia. In effected regions, many millions are at risk of arsenic-induced disease and strategies are required to provide safe water for consumption. The main strategies available are mitigation (the provision of alternative arsenic-free water) and remediation (arsenic removal from extracted water). Consideration of local conditions suggests that for many areas remediation, at an affordable cost, is the only practical option. Remediation technologies are available, but most have been developed for industrial-scale arsenic removal at central water treatment plants. The options for local / personal treatment of water are less well developed. The available methods include arsenic removal by precipitation / co-precipitation and filtration, removal by adsorption onto artificial and natural sorbents, water softening with lime, ion exchange onto activated alumina, membrane processes and bioremediation. This review considers the technical aspects and the appropriateness of these options.  相似文献   
77.
Journal of Soils and Sediments - The aim of the study was the calculation of geochemical, ecological, and ecotoxicological indices for the assessment of risk resulting from the presence of trace...  相似文献   
78.
Journal of Soils and Sediments - The aims of the study were to investigate the interaction between fractions of organic matter and polycyclic aromatic hydrocarbons (PAHs) in bottom sediments and to...  相似文献   
79.
The objective of this experiment was to assess the effect of interaction between early and late nitrogen (N) fertilization on grain yield, protein content, and distribution of N between organs of winter wheat. Wheat was grown in pots in vegetation house. Experiment has been carried on in three years 2001–2003, each year in four replications. Wheat supplied with 0.9, 1.4, 1.9, 2.4, and 2.9 g N/pot was top dressed at anthesis by 0.85 g labeled nitrogen 15N/pot. Plants supplied with 0.9 g N/pot enhanced grain yield by 28% and gluten content by 62% and plant supplied with 2.9 g N/pot by 27% and 13%, respectively. The amount of 15N fertilizer stored in plant organs decreased proportionally to the amount of previously accumulated nitrogen, but the share of 15N in plant parts was almost constant. Grain accumulated about 86% of total 15N taken up by plants. Irrespective on nitrogen status prior to anthesis, about 50% of 15N has been used for gluten formation. The percentage of 15N recovery fraction ranged from 79% to 86%.  相似文献   
80.
As ecosystem engineers, earthworms play a key role in the soil environment. However, due to increasing anthropogenic pressure, soil organisms,including earthworms, are being threatened by habitat loss. In this study, we undertook a qualitative and quantitative investigation of earthworms of the family Lumbricidae in four types of Carpathian beech woodland(Fagetum carpaticum), characterized by their understory vegetation(I, F. c. festucetosum drymejae; II, F. c. typicum; III, F. c. lunarietosum; and IV, F. c. allietosum), in the Bieszczady National Park(Eastern Carpathians, Southeast Poland). At each investigated site, soil monoliths(25 cm × 25 cm × 25 cm) were examined by hand sorting. Earthworms were expelled from deep soil layers using a weak formalin solution(0.4%). Depending on the phytocoenosis, 7 species of Lumbricidae were identified at each of the sites I, II, and III and 10 at site IV. Site IV(F. c. allietosum) differed significantly(P 0.05) from the other three sites with respect to earthworm biomass(59.71 ± 39.53 g m~(-2))and the Shannon-Wiener diversity index(0.52 ± 0.12). Although present three decades ago, the deep-burrowing species Octodrilus transpadanus and the litter-dwelling species Dendrobaena octaedra were not found at site IV in the present study. We suspect that these two species may have been displaced by the invasive Lumbricus terrestris, which was not found at the same site in the 1980 s. Such observations warrant further investigation to verify the predicted effects of an invasive earthworm, including the potential effects on soils and other fauna and flora, which have been documented in numerous countries.  相似文献   
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