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31.
Rasool  T.  Dar  A. Q.  Wani  M. A. 《Eurasian Soil Science》2020,53(3):362-376
Eurasian Soil Science - The quantification of spatial variability of soil properties is indispensable for evaluating the effectiveness of provisions undertaken to tackle various land surface...  相似文献   
32.
Soil fertility, one of the important determinants of agricultural productivity, is generally thought to be supplemented through the application of nutrients mainly through inorganic fertilizers. The physical fertility of the soil, which creates suitable environment for the availability and uptake of these nutrients, is generally ignored. The present study aims to characterize the soil physical environment in relation to the long term application of farm yard manure (FYM) and inorganic fertilizers in rice–wheat. The treatments during both rice and wheat crops were (i) farm yard manure @ 20 t ha−1 (FYM); (ii) nitrogen @ 120 kg ha−1 (N120); (iii) nitrogen and phosphorus @ 120 and 30 kg ha−1 (N120P30) and (iv) nitrogen, phosphorus and potassium @ 120, 30 and 30 kg ha−1 (N120P30K30) in addition to (iv) control treatment, i.e. without any fertilizer and/or FYM addition. The treatments were replicated four times in randomized block design in a sandy loam (typic Ustipsament, non-saline, slightly alkaline). Bulk density, structural stability of soil aggregates and water holding capacity of 0–60 cm soil layer were measured.

The average mean weight diameter (MWD) was highest in FYM-plots both in rice (0.237 mm) and wheat (0.249 mm) closely followed by that in N120P30K30 plots. The effect of FYM in increasing the MWD decreased with soil depth. The addition of both FYM and N120P30K30 increased the organic carbon by 44 and 37%, respectively in rice. The total porosity of soil increased with the application of both FYM and N120P30K30 from that in control plots. In 0–15 cm soil layer, the total porosity increased by 25% with FYM from that in control plots. This difference decreased to 13% in 15–30 cm soil layer. The average water holding capacity (WHC) was 16 and 11% higher with FYM and N120P30K30 application from that in control plots. The MWD, total porosity and WHC improved with the application of balanced application of fertilizers. The grain yield and uptake of N, P and K by both rice and wheat were higher with the application of FYM and inorganic fertilizers than in control plots. The carbon sequestration rate after 32 years was maximum (0.31 t ha−1 year−1) in FYM-plots, followed by 0.26 t ha−1 year−1 in N120P30K30-plots, 0.19 t ha−1 year−1 in N120P30 and minimum (0.13 t ha−1 year−1) in N120-plots.  相似文献   

33.
34.
A pot experiment was conducted to appraise the inhibitory effects of salt stress on biochemical attributes in the three mungbean cultivars (NCM-209, NCM-89 and NM-92). Salt stress caused a significant decrease in plant height, shoot relative water contents, photosynthetic pigments, endogenous levels of K+ and K+/Na+ ratios and increase in cellular levels of H2O2, MDA, Na+ and Cl?. However, cv. NCM-209 was found to be tolerant in terms of lower salt-induced decline in K+, K+/Na+ ratio and photosynthetic pigments. The endogenous levels of H2O2 and MDA were also lower in cv. NCM-209. Salt stress markedly also affected different yield attributes in all mungbean cultivars. Again cultivar NCM-209 exhibited less inhibitory effects of salt stress on different growth attributes. Salt stress resulted in a marked increase in the activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase and ascorbate peroxidase) in mungbean cultivars. Activity of peroxidase was maximal in cv. NCM-209 and catalase activity was maximal in cv. NCM-89, whereas cvs. NCM-89 and NM-92 showed higher activities of superoxide dismutase. Similarly activity of ascorbate peroxidase was higher in cv. NM-92. It could be inferred from data of antioxidant enzymes that mungbean cultivars cannot be categorized as salt tolerant or sensitive on the basis of a single antioxidant enzyme.  相似文献   
35.
Abstract

Vegetative cover plays an important role for the quality of soil especially in hilly and mountainous areas such as Azad Jammu and Kashmir where erosion is a major threat to the ecosystem and productivity. The study focuses on the impact of land-use types on soil quality by measuring the differences in chemical and physical properties at three sites in adjacently located natural forest land (forest), fallow grassland (grass) and arable land (arable). Soil samples from 0-15 and 15-30 cm depth were collected and examined for particle distribution, dry bulk density, organic matter (OM), pH, macro- and micro-nutrients. Land-use types had a significant effect on primary soil particle distribution. Highest clay content was found in forest and highest sand content in arable. Forest had relatively the highest levels of OM, macro- and micro-nutrients and arable the lowest. Most of the properties of the 0-15 cm surface level of grass were similar to those observed in the 15-30 cm level in forest. Arable exhibited lowest nutrient status and poorest physical conditions, indicating a degrading effect of arable cultivation practices on soil. Grass and arable showed, compared to forest, a 30–60% average increase in bulk density and 26–66% average decrease in OM. Regression analysis showed a significant correlation of OM with available phosphorus and potassium while it had negative correlation with dry bulk density and pH. Natural vegetation appeared to be a main contributor of soil quality as it maintained the organic carbon stock, and increased the nutrient status of soil and is therefore important for sustainable development of Azad Jammu and Kashmir and other similar areas. Furthermore, OM was shown to be an important indicator of soil quality.  相似文献   
36.
Summary

The aim of this study was to evaluate the anti-oxidant activities of petroleum ether, methanol, ethyl acetate, and aqueous extracts of the aerial parts and inflorescences of the herb, Artemisia amygdalina Decne. Methanolic extracts of the aerial parts and aqueous extracts of the inflorescences gave the maximum levels of inhibition (90.6% and 76.4%, respectively) in the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay when compared to ascorbic acid, which showed 77.9% inhibition. The superoxide radical scavenging activity was highest in methanolic extracts of the aerial parts and in methanolic extracts of inflorescences (94.3% and 88.5%, respectively). These values were comparable to the reference standard, ascorbic acid, which showed 92.8% superoxide radical scavenging activity. In the deoxyribose assay, α-tocopherol showed 50.1% inhibition, while methanolic extracts of the aerial parts and inflorescences showed 46.2% and 46.4% inhibitory activity, respectively, against hydroxyl radicals. In the ferric thiocyanate assay, petroleum ether extracts of the aerial parts showed 78.7% inhibition, while ethyl acetate extracts of inflorescences showed 80.2% inhibition. The commercial standard, α-tocopherol, showed 79.7% scavenging activity. Extracts of A. amygdalina may provide an alternative source of natural anti-oxidant activity.  相似文献   
37.
Aquaculture International - This study was performed to investigate the effects of dietary acetic acid, probiotic protexin, and their combination on growth performance, intestinal microbiota,...  相似文献   
38.
Outbreaks of buffalopox or pox-like infections affecting buffaloes, cows and humans have been recorded in many parts of the world. Since the first outbreak in India, a large number of epidemics have occurred. Unlike in the previous years, generalized forms of the disease are now rare; however, there are severe local forms of the disease affecting the udder and teats, leading to mastitis thereby undermining the productivity of milk animals. The causative agent buffalopox virus (BPXV) is a member of the Orthopoxvirus, and is closely related to Vaccinia virus (VACV), the type-species of the genus. Earlier studies with restriction fragment length polymorphism and recent investigations involving sequencing of the genes that are essential in viral pathogenesis have shown that BPXV is phylogenetically very closely related to VACV and may be considered as a clade of the latter. The review discusses the epidemiology, novel diagnostic methods for the disease, and molecular biology of the virus, and infers genetic relationships of BPXV with other members of the genus.  相似文献   
39.
The preliminary analysis of data from the Pioneer 10 S-band radio occultation experinment has revealed the presence of an ionosphere on the Jovian satellite Io (JI) having an electron density peak of about 6 x 10(4) electrons per cubic centimeter at an altitude of approximately 60 to 140 kilometers. This suggests the presence of an atmosphere having a surface number density of about 10(10) to 10(12) per cubic centimeter, corresponding to an atmospheric surface pressure of between 10(-8) and 10(-10) bar, at or below the detection threshold of the Beta Scorpii stellar occultation. A measurement of the atmosphere of Jupiter was obtained down to the level of about 80 millibars, indicating a large temperature increase at about the 20 millibar level, which cannot be explained by the absorption of solar radiation by methane alone and can possibly be due to absorption by particulate matter.  相似文献   
40.
Leaf protein concentrate (LPC) fortified dishes were compared with isoproteinous and isocaloric amounts of milk for the supplementation of the normal diets of the children of a local slum: 40 children were fed LPC-fortified dishes as a supplement and 40 other children were fed milk as a supplement; 20 children who were not given any supplements served as a control group. Data on increases in height and weight and on haemoglobin and red blood cell status confirmed that the LPC-fortified dishes were comparable to milk as a supplement to provide protein, minerals and vitamins to nutritionally inadequate local diets.  相似文献   
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