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91.
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ABSTRACT

A field trial was conducted at Rajasthan Agricultural University, Bikaner, India, in the summers of 2002 and 2003 to determine the effect of sulfur (S) in improving iron (Fe) nutrition of mungbean (Vigna radiata L.) grown on calcareous soils. The experiment was laid out in a split-plot design with three replications. Four levels of sulfur (0, 20, 40, and 60 kg S ha?1) were applied in main plots. In sub-plots, eight levels of Fe were replicated. Three levels of Fe were applied as a basal application of FeSO4 (0, 12.5, and 25.0 kg FeSO4 ha?1) and the remaining five were applied as a foliar application of 0.5% FeSO4 at branching, flowering, and at both branching and flowering with or without 0.1% citric acid. The results of the experiment revealed that application of sulfur at the higher doses had a significant positive effect on activities of catalase, ascorbate peroxidase, guaiacol peroxidase, synthesis of chlorophyll, and active Fe content of green leaves compared with lower doses. Application of 0.5% FeSO4 and 0.1% citric acid at both branching and flowering had no effect. The best results were recorded with basal application of 25.0 kg FeSO4 in combination with 40 kg S ha?1. The frequency of foliar application had an appreciable effect on chlorophyll synthesis, enzymatic activities, and active Fe content in green leaves. Plants that received foliar application of 0.5% FeSO4 + 0.1% citric acid at both branching and flowering responded more than those that received treatment at either branching or flowering. For best results, it is suggested to use 25.0 kg FeSO4 ha?1 in a basal application along with 40 kg S ha?1, as plants require most of their S and Fe at the early growth stages.  相似文献   
94.
A true‐breeding black gram (Vigna mungo) × green gram (Vigna radiata) derivative was reciprocally crossed with adzuki bean, Vigna angularis. Pollinated pistils were treated with gibberellic acid (GA3) (70 p.p.m.) 24 and 48 h after pollination. One fertile pod containing two hybrid seeds was obtained, when V. angularis was used as the male parent. One of these seeds germinated and a partly fertile interspecific hybrid was obtained. Its hybridity was confirmed at the seedling stage based on the presence of the green epicotyl colour of the adzuki bean. Pubescence of epicotyl, stem, leaf margins and pod, and the colour of the mature pod, characteristics of the black gram × green gram derivative, were also expressed in the hybrid. In addition, the hybrid exhibited two novel traits — the presence of racemose inflorescence and plant regeneration ability — not present in the parents. The study of this hybrid and four offspring revealed that green epicotyl colour of adzuki bean, and the pubescence of stem and leaf margins of the black gram × green gram derivatives were dominantly inherited traits. Colours of epicotyl and stem bases were found to be linked.  相似文献   
95.
Aqueous sprays containing either (1) micronutrients (Fe, Mn, Cu, Zn, B) at a concentration of 5 × 104M, (2) 2, 4-D at 1 ppm or (3) the micronutrients and 2, 4-D together were applied to 2-week-old plants of green bush bean, Phaseolus vulgaris. Measurements of juvenile growth were made 5, 10 and 15 days after treatment; of green pod yield and ascorbic acid content 6 weeks after treatment; and of seed yield when the plants were 13 weeks old. The use of 2, 4-D and of the 2, 4-D-micronutrient sprays resulted in significant (P = 0.05) increases in stem height, leaf number and area, and fresh and dry weights of roots, stems and leaves at all three times of harvest. The yield of green pods, in terms of number and fresh weight per plant, and the pod vitamin C content at harvest and after 4 days’ storage were significantly larger in the treated plants. In all cases the greatest stimulation resulted from the use of the solution containing both the 2, 4-D and microelements. Application of the solution containing only microelements produced values which did not differ significantly from those of control plants.  相似文献   
96.
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A set of 99 common bean germplasm collected from central Himalaya was investigated for their genetic variability using random amplified polymorphic DNA (RAPD) markers. Ten oligonucleotide primers, selected from 60 initially screened, generated 123 amplicon products. Of these, two amplicons were shared by all the accessions whereas 112 were polymorphic at least in two pair wise comparison. Nine unique bands identified were as low as 0.32 kb M.W. to as high as 3.5 kb and were confined to eight collections. All primers produced polymorphic amplicons though the extent of polymorphism varied with each primer. The primer OPF-17 was found to be most powerful and efficient as it generated a total of 17 bands of which 15 were polymorphic. RAPD markers data were analysed statistically using NTSYSpc.2.02e software and a dendrogram was generated using Jaccard’s similarity coefficient. The similarity coefficient values varied from 0.19 to 0.91. Grouping analysis revealed the categorization of 99 germplasm into 12 major branches with different level of similarity. Three branches namely branch 2, 3 and 5 out of 12 had only one accession. Branch 1 which consisted of three accessions was the most divergent as revealed by Jaccard’s similarity coefficient. Branching pattern of the accessions did not show any correlation with morphological data or altitudinal alignment of the accessions.  相似文献   
98.
This is a study of the influence of repeated laundering and the use of fabric softener in the context of mechanical properties of fabrics with respect to textile parameters. In the large competitive market of fabric softener, the fabric softener producers claim benefits for fabric hand as well as the mechanical properties of textiles. The main aim of this study is to investigate the influence of ageing and the use of fabric softener on the mechanical properties of textiles during their cradle to grave life with respect to fibre type, fibre fineness, knitting construction and number of wash cycles. The low stress mechanical properties were evaluated by means of the Kawabata Evaluation system for fabric (KES-F) and Universal Surface Tester (UST). The tensile, shear, bending, compression and surface properties and changes in these parameters due to wash-ageing and the use of fabric softener during laundry were evaluated. These mechanical properties or combinations of them are the deciding factors for comfort aspects of apparel during wear. Hence, these mechanical properties need to be correlated with the sensory attributes. In Part I, we examine the change in mechanical parameters due to wash-ageing and the use of softener, while Part II deals with Fuzzy-Logic modelling to correlate these mechanical parameters with sensory attributes.  相似文献   
99.
Field experiments were conducted during 1993/94 and 1994/95 in the sub-humid tropic environment of northern India to identify suitable irrigation schedule(s) for winter maize (December to May). Based on plant growth stages, viz. knee-high, tasselling, flowering, silking, grain-filling and dough, which occurred, respectively, at 55, 75, 95, 105, 125 and 145 days after planting, the crop was subjected to six irrigation treatments, which were: no irrigation (I0); irrigation given at all the growth stages (I1); irrigation missed at knee-high (I2); at knee-high and dough (I3); at knee-high, flowering and grain-filling (I4); and at knee-high, flowering, silking and dough stages (I5). The change in profile soil water content, (W (depletion) of the entire crop-growing season was found to be in the order I0 >I5 >I4 >I3 >I2 >I1. Of the total net water use (NWU), about 87% was evapotranspiration and 13% deep percolation losses. The NWU was highest (472 and 431 mm) under I1 and lowest (223 and 240 mm) under the I0 treatment during the two cropping seasons. Compared to I1, NWU in I3 decreased by 23% and 12.3% and in I4 by 33.8% and 24.2% in the two cropping seasons. However, there was no statistically significant difference (at LSD, P=0.05) between yields of the I1 to I4 treatments during either year. The NWU was found to be in the order I1 >I2 >I3 >I4 >I5 >I0, whereas the water-use efficiency (WUE) based on NWU was found to be in the reverse order: I5 >I4 >I3 >I0 >I2 >I1. Maximum yield (5.14 t ha-1) with WUE of 1.39 kg m-3 was obtained under the I3 treatment. However, optimum yield (4.91 t ha-1) with high WUE of 1.54 kg m-3 was under I4. Accordingly, irrigation applications greater than 240 mm did not provide additional yield of winter maize. Frequent irrigations (I1) proved detrimental to grain yield of winter maize in the northern Indian plains, especially under cool weather conditions, where minimum temperature (6°C) can be accompanied by occasional frost.  相似文献   
100.
Summary The kinetics of Zn absorption were studied in mycorrhizal (Glomus macrocarpum) and non-mycorrhizal roots of corn (Zea mays L.) at pH 6.0 at Zn concentrations of 75 mol to 1.07 mol m-3. Five concentration-dependent phases of Zn absorption were recognized; phase 0 (1.5–4.0 mmol m-3) was linear but the other four phases (4.0 mmol to 1.07 mol m-3) obeyed Michaelis-Menten kinetics. At low concentrations (less than 4 mmol m-3), sigmoidal kinetics of Zn absorption were observed. The absorption of Zn by mycorrhizal maize was greater at low concentrations but decreased at higher levels. This appeared to be a result of a higher maximal uptake rate in phase 1 and lower K m values in the subsequent phases. Kinetic models yielding continuous isotherms could not account for the observed multiphasic pattern.Research paper no. 6820 through the Director, Experiment Station, G.B. Pant University of Agriculture and Technology, Pantnagar 263 145, UP, India  相似文献   
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