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1.
Radiation use by oil seed crops — a comparison of winter rape, linseed and sunflower For the production of grain crops rich in oil, winter rape, linseed and sunflower are similarly suitable at many arable locations. We wanted to compare the extent to which radiation (PAR) is intercepted and utilized by the individual species for dry matter and yield production. For this purpose, a 2‐year field experiment comprising the factors genotype, N fertilization and soil tillage was conducted. For five phases of crop development, growth rates (CGR, RGR and NAR) and PAR utilization were calculated. At full ripeness, total dry matter, grain, oil and energy yields, the crop‐ and year‐specific PAR supply, its interception and utilization for dry matter production and the resulting energy binding were determined. Due to the different individual vegetation periods, the PAR supply of the crops differed. The crop assimilation areas also differed, with values for winter rape and sunflower higher than those for linseed. The yield productivity of winter rape and sunflower was also higher than that of linseed. N fertilization increased yield to different extents for the different crops. On average, winter rape and sunflower produced the same amounts of dry matter and energy yield. Due to a higher harvest index, sunflower had the highest grain yield, and because the oil concentration in grain was comparatively high sunflower produced the highest oil yield, too. Under cool and wet climate conditions, however, the productivity of sunflower is offset by a relatively high yield risk because of uncertain ripening. The highest PAR utilization by linseed did not compensate for its very short vegetation period in combination with the lowest PAR interception.  相似文献   
2.
Male Sterility in Barley   总被引:1,自引:0,他引:1  
The anther form and development of eight two-rowed genie male sterile barley mutants are abnormal. The male sterility in each mutant is conditioned by single non-allelic recessive genes. These mutant genes cause reductions in anther size and lumen diameter. Though in seven mutants, the male meiosis is normal until microspore liberation, the micro-spores abort in all cases after release from the PMCs. In one mutant, the microspores degenerate at the tetrad stage before release from the PMCs. In four mutants, the tapetal development and disintegration are normal, in four others they are abnormal. Despite these variations, the male sterility in all the eight mutants is complete.  相似文献   
3.
A model to describe the importance of different physiological processes to explain grain yield differences (ΔGw) between cropping systems (Huggins and Pan, 1993) was modified to evaluate the nitrogen use efficiency of different cereals. The method uses measurements of grain yield (Gw), grain N (Ng), above-ground plant biomass (B), above-ground plant N (Nt), applied fertilizer N (Nf), and post-harvest inorganic soil N in control plots without fertilizer (Nh). The components are N supply (Ns), N uptake efficiency (Nt/Ns), assimilation efficiency (B/Nt), harvest index (Gw/B) and N harvest index (Ng/Nt). For a first verification of the model different winter cereal species, i.e., one genotype of winter wheat, one of winter rye and one of spelt wheat, were compared in a 2-year field experiments at two sites with different soil fertility and climate. The modified nitrogen efficiency component analysis provided a good understanding of yield differences at different levels of applied N and soil fertility. The method could be useful for selection of genotypes with a high N use efficiency in breeding programmes.  相似文献   
4.
Attempt has been made to study the treatability of printing ink wastewatergenerated from an Indian currency printing press using coagulation-flocculation process. Coagulant agents, viz. ferrous sulphate, ferric chloride, aluminium sulphate and polyaluminium chloride were studied to select the most suitablecoagulant for effective treatment, and attain the optimum coagulant concentration. Cationic polyeletrolyte in conjunction with the most effective coagulant was also studied to assess its effect on floc settleability. Polyaluminium chloride (PAC) was found to be the most efficient coagulant, achieving removals of colour, suspended solids (SS), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of 95.9–96.5%, 96.5–97.0%, 61.3–65.8%and 54.8–61.8%, respectively at an optimum concentration of 1500 mg L-1. Other coagulants, viz. ferrous sulphate, ferric chloride and aluminium sulphate did not show substantial removals of colour, BOD and COD, except suspended solids in comparison to the performance of PAC. Cationic ploylectrolyte in combination with PAC at an optimum concentration of 1500 mg L-1 of PAC and 1.0 mg L-1 of polyelectrolyte further improved the removal efficiency of various parameters studied, in addition to improving the floc settling rate, and reduction in quantity of sludge generation.Effect of rapid mixing intensity expressed as mean temporal velocity gradient (G), and mixing time (t) on flocculation was also investigated. Rapid mixing at an impeller rotational speed (n) of 300 rpm and mixing time (t) of 60 sec indicated good floc formation, which resulted in achieving velocity gradient of 821 s-1, and was found to be an optimum combination. This was also indicated by relatively high settling velocity of sludge formed and low residual colour in the supernatant. However, slow mixing beyond 5 min, adopted after initial optimum rapid mixing, indicated negligible effect on flocculation.  相似文献   
5.
In this the first of a two-part report, results are given of investigations into the vertical distribution of the moisture content and density of wood and bark, as well as into bark thickness, bark mass and bark volume of two age groups of Pinus elliottii and P. patula trees and one of P. taeda. Variation in wood and bark properties was affected more by position in the stem than by species and age. This precludes the determination of reliable mass/volume conversion figures if stem position is not taken into consideration. The mass loss of logs of the above species after various periods of drying and the development of mass/volume conversion figures will form part of a further report.  相似文献   
6.
Introducing autumn-sown legumes into Central European farming systems could be beneficial for addressing two challenges for European agriculture, i.e., the substantial deficit of protein sources for livestock and expected changes in agroclimatic conditions. Therefore, a two-year field experiment was conucted under Pannonian climate conditions in eastern Austria to assess nitrogen (N) yield and N fixation of several winter faba bean varieties from different European countries as compared to a spring faba bean. Winter wheat was used as a reference crop for estimating atmospheric N fixation. Winter faba beans were susceptible to frost damage especially in the harder of the two winters. Winter faba bean varieties could not achieve a higher grain yield and a higher grain N yield than the spring faba bean but had a higher grain N concentration (except for one variety). Grain yield and grain N yield of faba beans were severely impaired by drought in one year (with a mean of varieties of 8.3 g N m?2, winter wheat: 6.4 g N m?2); in the other year, grain N yield of faba beans considerably surpassed that of winter wheat (with a mean of varieties of 21.5 g N m?2, winter wheat: 8.8 g N m?2). After harvest, faba beans left higher nitrate residues in the soil, especially in the subsoil, and higher amounts of N in above-ground residues compared to winter wheat. Faba beans showed high N fixation under optimum conditions (with a mean of varieties of 21.9 g N m?2) whereas drought considerably impaired N fixation (with a mean of varieties of 6.3 g N m?2; with no differences between autumn- and spring-sown faba beans). In conclusion, growing winter faba bean varieties in eastern Austria did not result in higher grain yield, grain N yield, and N fixation compared to growing a spring faba bean.  相似文献   
7.
Zusammenfassung Im Rahmen der Untersuchungen über den Metabolismus insektizider Chlorkohlenwasserstoffe mit Hilfe14C-markierter Verbindungen wird über den Abbau von Endrin, Heptachlor und Telodrin in Warmblütern, Pflanzen und Mikroorganismen berichtet; die entstandenen Metaboliten wurden zum Teil als Hydroxyl-Derivate der Insektizide identifiziert.Nach oraler Applikation von radioaktiv markiertem Endrin an Ratten — Endrin weist von allen diesen Insektiziden gegenüber Warmblütern die höchste Toxizität auf — wird die Radioaktivität sehr schnell ausgeschieden (Speicherung nach 13 Tagen, bei täglicher Applikation, 14% der Gesamtaktivität; drei Tage nach letzter Endrindosis 5,3%). Als Ausscheidungsprodukte treten, hauptsächlich in den Faeces, neben geringen Mengen Endrin zwei hydrophile Metaboliten auf.20 Tage nach Besprühen von Pflanzen (Brassica oleracea) mit Endrin-14C enthalten die Wurzeln größere Mengen eines hydrophilen Metaboliten, der auch in Stengeln, Blättern und im Erdreich nachgewiesen wurde.
Summary In the context of investigations of the metabolism of insecticidal chlorinated hydrocarbons by means of14C-labelled compounds this report deals with the degradation of endrin, heptachlor and telodrin in warm-blooded animals, plants and micro-organisms. The resulting metabolites were identified partly as hydroxyl derivatives of the insecticides.After oral application of radioactively labelled endrin in rats — endrin shows the highest toxicity among all insecticides towards warm-blooded animals — the radioactivity was very quickly eliminated (accumulation after 13 days' application was 14% of the total activity; 5,3% remained three days after the last dose of endrin). The waste products, appearing mainly in the faeces, were found to be, beside small quantities of endrin, two hydrophilic metabolites.20 days after plants(Brassica oleracea) were sprayed with endrin-14C the roots contained considerable amounts of a hydrophilous metabolite. The latter was also found in stems, leaves and in the soil.

Resumé Dans le cadre de recherches sur le métabolisme des insecticides à base d'hydrocarbures chlorés, effectuées à l'aide de composés marqués à14C, on expose les modalités de dégradation de l'endrine, de l'heptachlore et de la télodrine chez les animaux à sang chaud, chez les plantes et les micro-organismes; on a identifié une partie des métabolites obtenus comme dérivés hydroxyles des insecticides.Après l'administration par voie buccale à des rats d'endrine marquée, qui a, de tous ces insecticides, la plus grande toxicité pour les animaux à sang chaud, la radioactivité était très vite éliminée. L'activité résiduelle totale était de 14% après qu'on leur avait administré une dose quotidienne d'endrine pendant 13 jours et de 5,3% trois jours après la dernière administration. Parmi les produits éliminés, surtout dans les fèces, il faut citer, à côté de quantités réduites d'endrine, deux métabolites hydrophiles.20 jours après la pulvérisation des plantes(Brassica oleracea L) avec de l'endrine-14C, les racines contenaient des quantités appréciables d'un métabolite hydrophile, que l'on a aussi détecté dans les tiges, les feuilles et le sol.


mit 11 Fig.  相似文献   
8.
Of the four high-protein genotypes isolated after induced mutations and breeding, two exhibited height and yield nearly equal to the Bonneville pea variety, but matured later. Their stability for protein yield over generations and locations, aminogram pattern and nutritional value remains to be determined. Path analysis and correlations indicate that developing a short-statured pea with higher yield and increased protein content may not be possible with the available breeding methods and germ plasm.  相似文献   
9.
Eight non-allelic male-sterile mutants controlled by a single recessive gene were induced in garden pea (Pisum sativum) after EMS, DES and gamma-ray-mutagen treatments singly and in combination. These mutants differ in the time and type of tapetal development due to differential action of male-sterile (ms) genes over the sporogenous and non-sporogenous anther tissue. In the msg1 mutant, the sporogenous tissue breaks down during premeiosis, followed by tapetal degeneration. In msg2, sporogenous tissue and tapetal tissue exhibit anomalies at early and late prophase 1, respectively. Although in msg3 and msg5 the ms gene action over sporogenous tissue initiates during early and late prophase, respectively, the tapetal tissue breaks down during post-meiosis. In msg6, anomalies in the sporogenous tissue appear during prophase II, but the tapetum degenerates during the mononucleate stage. Although both the tapetal and sporogenous tissue anomalies appear simultaneously at pachytene in msg4, the tapetal breakdown is delayed until the microspore stage. In msg7 and msg8, anomalies in both these tissues occur simultaneously during the tetrad and post-meiotic stages, respectively. Despite differences in the timing of tapetal and sporogenous tissue breakdown, tapetal development is normal in msg1, msg5, msg6, msg7 and nisg8 but abnormal in msg2, msg3 and msg4. The ms gene action is dual in msg2, msg3 and msg4 but single in msg1, msg5, msg6, msg7 and msg8. In all these mutants, the time of tapetal anomaly exhibits no correlation with the time of ms gene action. The gene for open flower found in one male-sterile mutant needs to be introduced into fertile peas for commercial hybrid-pea breeding.  相似文献   
10.
The investigations were based on biennial field trials carried out at two locations comprising the factors location/previous crop, winter cereal genotype (rye cv. ‘Farino’,triticale cv. ‘Modus’, wheat cv. ‘Batis’) and production intensity level. One agronomical focus was to replace the mineral N‐supply due to its energetic relevance, by either the residues of legumes, or stillage, a processing residue containing organic N. The measurement included the crop yield ha?1, the bioethanol exploitation dt?1 and the bioethanol yield ha?1. The last was closely correlated to the grain yield and thus dominated by intensity level. Highest bioethanol yields with an average peak at 4022 l ha?1, always occurred at the highest intensity level. Bioethanol exploitation however, was mainly determined by the genotype. The cultivars showed significant exploitation and yield differences. An adequate bioethanol exploitation was observed with the wheat cv. Batis in contrast to diminished grain and bioethanol yields. Considering bioethanol exploitation and bioethanol yield, the triticale cv. Modus was the outstanding genotype. Despite high grain yields, the bioethanol yields of the rye cv. Farino stayed mean, because of a genotypic lowered bioethanol exploitation. Comparing the approaches of mineral nitrogen substitution, legume N was successful, whereas stillage fertilizing, according to the examined conditions, resulted in ample decreased grain and bioethanol yields ha?1.  相似文献   
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