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31.
Two fungal strains were used to evaluate the relative nutritive value of various cereals and legumes.Aspergillus flavus Link ex Fr., isolated from spoiling bread crumbs, was tested on two sets of samples at equal nitrogen level. One comprised of 4 cereals and 19 legumes and the second included 25 barley strains, ranging in protein content from 7.7 to 17.8 percent. Total dry weight of the mycelium produced was used was used as the index of biomass.A. flavus was able to differentiate between different species of grain and also between different varieties within a species. A lysine dependent strain ofNeurospora crassa Shear and Dodge, was used to test 25 barley strain. The milled samples were administered, at equal nitrogen level with excess of starch and vitamins. In both the fungi biomass was positively correlated with protein quality.  相似文献   
32.
Tubers of three potato cultivars were stored at room temperature (20–39°C, 30–75% RH), under an insulated storage run on passive evaporative cooling (16–30°C, 70–90% RH) and a refrigerated storage (2–4°C, 90–95% RH) for 14 weeks and studied periodically for storage losses, reducing sugar content and dry matter percent of tubers, in order to explore the possibility of storing potatoes for processing at higher temperatures. Physiological losses in tubers remained less than 10% until 12 weeks of storage under evaporatively cooled storage. Reducing sugar contents increased by only 52.4–242.1% in tubers stored in evaporatively cooled storage as compared to 90.5–484.2% increase in tubers stored in refrigerated storage until 14 weeks. Potatoes stored in evaporatively cooled store were more suitable for processing into chips and french fries due to lower physiological losses and lower reducing sugar content of tubers.  相似文献   
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34.
Serum antibody titres to canine distemper virus (CDV), canine parvovirus (CPV) and rabies were measured in dogs that had not been revaccinated annually and compared with the titres in a control group of regularly vaccinated animals; 83 per cent (171 of 207) of the dogs vaccinated against CDV one or more years earlier had serum neutralising antibody titres equal to or greater than 16; 64 per cent (136 of 213) of the dogs vaccinated against CPV one or more years earlier had haemagglutination inhibiting titres equal to or greater than 80; and 59 per cent (46 of 78) of the dogs vaccinated against rabies two or more years earlier had serum neutralising antibody titres equal to or greater than 0.5 iu/ml. Three weeks after a single booster vaccination the dogs' antibody titres against CDV had increased above the threshold level in 94 per cent of the dogs, against CPV in 68 per cent, and against rabies in 100 per cent.  相似文献   
35.
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   
36.
Investigations on the adjustment of nitrogen supply from different N sources to the N uptake of maize A two years field experiment was conducted to study the effects of the nitrogen fertilizers: wheat swill, BASAMMON (NH4 + nitrification inhibitor DCD) and calcium ammonium nitrate (CAN) applied at N rates of 0.60.120 or 180 kg N/ha on yield, N uptake and soil mineral N residues of maize for silage or grain production. CAN was either broadcast or placed in the maize rows, with or without the addition of an Azospirillum-biopreparation (AZOGREEN). Due to initially high soil mineral N contents (50–70 kg N/ha) and a high mineralization from the soil (unfertilized: 100–170 kg N/ha), neither effects of fertilizer type, nor interactions between fertilizer type and N rate on biomass production and N uptake of maize were observed. The economically optimum total dry matter production and grain yield were obtained with a fertilization of 60–120 kg N/ha. In contrast to the biomass production the soil mineral N was considerably influenced by fertilizer type and N rate. The nitrate content of the soil increased during the early developmental stages of maize after an early application of swill or BASAMMON, and also during the ripening period after a late high dose of CAN. Though the placement of CAN was reflected in the soil, the soil nitrogen content per unit area could not be much reduced by row fertilization. The effects of AZOGREEN were only small. The results were greatly influenced by the high mineralization potential at the experimental site.  相似文献   
37.
The effect of the chelating agent ethylenediaminetetraacetic acid (EDTA) on the structure and function of endoglucanase is studied. In the presence of 2 mM EDTA, endoglucanase showed an enhanced enzymatic activity of 1.5-fold compared to control. No further change in activity was observed with increase in the concentration of EDTA to 5 mM. The K(m) values for control and in the presence of EDTA are 0.060 and 0.044%, respectively, and K(cat) was 1.9 min(-1) in the presence of EDTA. The kinetic parameters indicated a decrease in the K(m) with an increase in the K(cat). Far-ultraviolet circular dichroism (far-UV-CD) results showed a 20% decrease in ellipticity values at 217 nm in the presence of EDTA compared to native enzyme. The apparent T(m) shifted from a control value of 57 ± 1 to 76 ± 1 °C in the presence of EDTA (5 mM). The above results suggested that the enhanced activity in the presence of EDTA is due to an increase in the K(cat) and flexible conformation of the enzyme. The stability of endoglucanase increased in the presence of EDTA.  相似文献   
38.
Spring-sown crops are expected to have a higher risk of drought during summer in the next decades in Central Europe due to expected climate change. Therefore, a two-year experiment was conducted under Pannonian growing conditions in Eastern Austria to investigate the effect of autumn- and spring-sowing of facultative wheat. Autumn-sowing of facultative wheat enhanced crop development, soil coverage, crop stand height, crop growth rate, and nitrogen (N) utilization efficiency during the vegetation period compared to spring-sowing; duration of growth stages was prolonged and crops were earlier ripe. In contrast, spring-sowing resulted in higher relative growth rates, higher N concentrations of aboveground dry matter, higher relative N uptake rates, and more mineral N in the soil. At harvest, grain yield and yield components ears m?2 and thousand kernel weight (TKW) were higher in autumn-sown than in spring-sown wheat, resulting thereby in an increased seed yield. Spring-sown wheat had higher N concentrations in grain and in straw. Anyhow, N yield was slightly higher with autumn-sowing due to the higher grain and straw yields. Grain and straw yield, plant stand height, ears m?2, and TKW were impaired in the second experimental year by a severe drought for both sowing dates as well as N concentrations and N yields of grain and straw, partial factor N use efficiency and N utilization efficiency. But the yield components harvest index, grains m?2, and grains ear?1 were strongly impaired with spring-sowing under drought conditions. Thus, autumn-sowing of wheat resulted in higher yield stability across both years, based on these yield components highlighting possible benefits of autumn-sowing with expected summer drought under climate change.  相似文献   
39.
The influence of three levels of nitrogen fertilization on the grain yield, protein and starch make up of three varieties of rice: IR-8, Sabarmati, and Basmati-370, was studied in a field experiment. Part of the nitrogen was applied through foliar spraying at the time of anthesis. The grain protein and amylose content of developing caryopsis was studied. Significant increase in yield and crude protein content was recorded but the amylose content decreased slightly with increased nitrogen fertilization. Five of the essential amino-acids, reported, increased with fertilization. Lysine content increased steadily when expressed on protein as well as meal basis. Contrary to the expectation, the two dicarboxylic amino acids did not increase significantly.  相似文献   
40.
Genotype-by-environment interactions (GEI) have been identified as an important component of the genotypic variation for grain and stover yield traits of rabi sorghum varieties and hybrids in India. It has been argued that obtaining an understanding of the causes of these GEI is an important step to identify the scope for genetic improvement of grain and stover yield by conventional breeding. Pattern analysis was used to investigate the regional structure of the GEI for the four traits grain yield, stover yield, days-to-flower, and plant height, measured on the varieties and hybrids tested over 10 years in the All India Coordinated Sorghum Improvement Program (AICSIP). There was evidence that regional differences accounted for part of the GEI for grain yield and days-to-flower but not for stover yield and plant height. Cluster analysis was used to group the locations included in the ACSIP experiments. The five-group level was chosen to examine the causes of GEI among the location groups. Hypotheses were proposed for the observed regional grouping of trials for grain yield. One group of trials consisted of predominantly irrigated trials, the other four groups differed in the timing and intensity of drought stress imposed on the entries. This retrospective analysis provides a basis for testing the hypothesised contributions of environmental variation in water availability to regional GEI for grain and stover yield. If these hypotheses are substantiated, the current multi-environment testing strategy used for the AICSIP trials could be modified to ensure adequate sampling of the five regional groups identified by the retrospective pattern analysis.  相似文献   
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