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31.
32.
The production of oil from the conventional oilseed seed crops (viz. mustard, rapeseed) is not sufficient to meet the demands of Pakistani people. Due to this reason, a surplus quantity of oil is imported every year from different countries to fulfill the domestic demands of the cooking oil. This 2-year study was aimed to optimize the dose of NPK for profitable production of white mustard. Nitrogen (0, 60, 90?kg ha?1), phosphorous (0, 30, 60?kg ha?1) and potassium (0, 75, 100?kg ha?1) were applied in various combinations. The results indicated that highest seed yield and profitability was recorded with NPK at 90–60–100?kg ha?1, which was attributed to improvement in crop growth. In crux, application of NPK at pre-optimized rate might be a viable option to improve the growth, yield, oil quality, and economics of white mustard production under arid climates in Pakistan. According to the results, a balanced use of NPK fertilization is a key management strategy for white mustard growing farmers of arid region.  相似文献   
33.
In this research we explore the potential of precision surface irrigation to improve irrigation performance under the warabandi system prevalent in the Indus Basin Irrigation System. Data on field dimensions, field slopes along with characteristic soil infiltration properties and outlet discharge were collected through a survey of a sample tertiary unit of Maira Branch Canal, Khyber Pakhtunkhwa Province, Pakistan. The performance of all fields in the tertiary unit was analysed and reported in aggregate, with detailed results of one field presented for illustration. The objective is to determine the optimum field layout, defined as the number of border strips, for the observed field characteristics to maximize performance. The results indicate that performance improvement is relatively easily achievable through changes in field layout within current irrigation services. Estimated application efficiency is sensitive to the selected depth of application, and it is important that a practical depth of application is selected. We recommend a depth of application of 50 mm and show how this is achievable and leads to a low quarter distribution uniformity of 0.750 and an application efficiency of 80 %. We also explore the feasibility of a 10-day warabandi rather than the 7-day warabandi and show that there is no significant change in the performance under a 10-day warabandi.  相似文献   
34.
Random amplified polymorphic DNA (RAPD) markers were used to estimate the genetical variability of three salt-resistant genotypes, SARC-1, SARC-5 and S-24, exposed to saline environment. High-yielding and salt-sensitive variety MH-97 was used as standard for comparison. The behavior of these genotypes under saline environment was analyzed by using the hydroponics screening methods at the seedling stage. One hundred and fifty primers were tested of which 52 primers revealed differences between SARC-1 and SARC-5, 54 revealed differences between SARC-1 and S-24 and 61 revealed differences between SARC-5 and S-24. Polymorphism differences between MH-97 and SARC-1, MH-97 and SARC-5 and MH-97 and S-24 were 53%, 64% and 42%, respectively. Four primer pairs amplified special fragments, which were located in all the three salt-resistant genotypes but none on the salt-sensitive genotype MH-97. Primer GLD-15 (5?-CCGTGGCATT-3?) generated a prominent fragment of length 1460 bp; primer GLF-18 (5?-ACCCGGAACC-3?) produced a fragment of length nearly 980 bp in the salt-resistant genotype; the primer pair GLE-5 (5?-TTCAAGCCCG-3?) located one polymorphic amplified band of 1290 bp and the primer GLH-9 (5?-ATCCAGGTCA-3?) performed as a weak polymorphic band of 640 bp, respectively.  相似文献   
35.
Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most of the animals were emaciated. Diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. Intestinal pathology was observed in 29% of buffaloes and 32.8% of cattle. Number of mesenteric lymph node (MLN) showing gross lesions was a bit higher (35.6%) in cattle than buffalo (31.2%). Acid-fast staining of tissue scraping smears revealed the presence of acid-fast bacilli (AFB) in 17.4% intestinal and 16.4% MLN tissue samples in buffalo, while in cattle 19.2% intestinal and 17.8% MLN were found positive for AFB. In buffaloes, PCR confirmed 12.8% intestinal and 12.4% MLN positive samples for M. avium subsp. paratuberculosis. However, in cattle, PCR analysis demonstrated 14.2% positive results for M. avium subsp. paratuberculosis in both MLN and intestinal tissue samples. PCR also confirmed M. bovis in 5.8% of cattle and 5% of buffalo MLN and intestinal tissues. PCR positive tissue samples for M. avium subsp. paratuberculosis were from those animals which were emaciated, having diarrhea, and severe gross lesions. AFB were also detected in tissue scraping smears of these animals. It is concluded that infection by various mycobacterium species can be differentiated by PCR, which is not possible by acid-fast staining technique.  相似文献   
36.
A 6-year-old Hereford embryo donor cow was referred to Auburn University College of Veterinary Medicine for a mass in the tip of her left uterine horn. The cow had recently undergone an embryo collection which yielded unfertilized, degenerated ova. Transrectal palpation and ultrasound revealed a multi-locular mass enveloped by two separate compartments that resembled an amniotic and allantoic cavity within the uterus. Tissue was collected via a uterine flush and submitted for histopathology. The tissue was determined to be placenta, confirming the diagnosis of a molar pregnancy. Following treatment, the cow was able to produce numerous viable embryos. Molar pregnancies are rare and characterized by abnormal growth of trophoblastic cells leading to formation of intrauterine cystic masses. It is important to routinely perform an ultrasonographic examination of the cow's reproductive tract approximately 30 days following non-surgical in vivo embryo collections to detect and treat unwanted conditions such as pregnancy and cystic conditions.  相似文献   
37.
This study identifies the potential use of the combined application of hardwood-derived biochar (BC) and phytohormone-producing endophytes for enhancing crop production under heavy metal stress. For this purpose, the endophyte Galactomyces geotrichum WLL1 was isolated from Trapa japonica inhabiting a Korean river whose rainfall catchment area included an abandoned zinc mine. Pyrolyzed BC derived from pine hardwoods was obtained commercially. Under growth chamber conditions, the combined or individual application of G. geotrichum WLL1 and BC (15 % w/w) significantly improved soybean growth with or without excess Zn (5,253.6 mg kg?1). The beneficial effect of treatments was observed in the low uptake of Zn by different plant tissues and its immobilization in the soil. Biochar and G. geotrichum WLL1 shared their beneficial properties synergistically and improved plant growth characteristics with or without Zn heavy metal stress (HMS). Further, intensive root colonization of G. geotrichum WLL1 in the presence of BC was observed irrespective of HMS. Most interestingly, BC and G. geotrichum WLL1 had a priming effect by inducing systemic resistance in soybeans as revealed by significantly large amounts of jasmonic acid. These properties of BC could be exploited under abiotic and biotic stress. Here, for the first time, the combined application of hardwood-derived BC and phytohormone-producing endophytes is recommended for environmentally friendly and cost-effective crop production under HMS.  相似文献   
38.
Acquired immunodeficiency syndrome (AIDS) is a chronic and potentially fatal ailment caused by the human immunodeficiency virus (HIV) and remains a major health problem worldwide. In recent years, the research focus has shifted to a greater emphasis on complementing treatment regimens involving conventional antiretroviral (ARV) drug therapies with novel lead structures isolated from various marine organisms that have the potential to be utilized as therapeutics for the management of HIV-AIDS. The present review summarizes the recent developments regarding bioactive peptides sourced from various marine organisms. This includes a discussion encompassing the potential of these novel marine bioactive peptides with regard to antiretroviral activities against HIV, preparation, purification, and processing techniques, in addition to insight into the future trends with an emphasis on the potential of exploration and evaluation of novel peptides to be developed into effective antiretroviral drugs.  相似文献   
39.
Quinoa is gaining importance on global scale due to its excellent nutritious profile and environmental stress‐enduring potential. Its production decreases under high salt stress but can be improved with paclobutrazol application. This study showed involvement of some potential protective mechanisms in root and leaf tissues of quinoa plants treated with paclobutrazol (PBZ) against high salinity. The treatment levels were based on preliminary experiments, and it was found that salt stress (400 mm NaCl) markedly reduced growth and photosynthetic pigments while PBZ (20 mg/L) application significantly improved these attributes. Stomata density and aperture declined on adaxial and abaxial surfaces of leaves due to salinity. Paclobutrazol application significantly improved the stomatal density on both surfaces of leaves. Concentration of proline and soluble sugars increased in root and leaf tissues under salinity, which was more obvious in PBZ‐treated plants. Salinity stress induced the oxidative damage by increasing lipid peroxidation (MDA) level in roots and more specifically in leaf tissues. However, PBZ treatments ameliorated the drastic effects of salinity and markedly reduced oxidative damage in salt‐stressed quinoa plants. Enhanced activity of enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) was triggered by PBZ application, more pronounced in leaf than root tissues. Based on these findings, we conclude that PBZ application improves the salt tolerance in quinoa by activation of the above‐mentioned physiological and biochemical mechanisms specifically in leaves.  相似文献   
40.
Salt tolerance is a physiologically and genetically complex trait controlled by multiple genes. To analyze the genetic basis of salt tolerance we evaluated 18 F1 along with their nine parents under three salt stress levels i.e. control, 10 dS m−1 and 15 dS m−1 in the summer of 2017 and 2018. Data were recorded for the number of bolls, seed cotton yield, boll weight, Na+, K+, K+/Na+ ratio, H2O2, SOD, POD, CAT and TSP. Line × tester analysis indicated that the contribution of lines was greater than testers. Except for Na+, most of the traits were controlled by non-additive genes. With the rise of salt stress, SCA variances increased and were higher than GCA variances for most of the traits indicating the traits were controlled by a few largely dominant genes. KEHKSHAN, FH-118 and FH-114 were found good general combiner whereas the cross KEHKSHAN × FH-114 was a good specific combiner and also indicated significant better parent heterosis for most traits during two years under salt stress and can be utilized in a breeding programme for salt tolerance.  相似文献   
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