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1.
Arid climate has contributed to crops yield production decrement in many regions due to water shortage and soil salinization. The main target of this research is to enhance wheat production under arid climate stresses by utilizing bio-elicitors. Two common wheat assortments i.?e. cv. Gemmiza 10 and Sakha 93 accomplished tolerant to these stresses utilizing bio elicitors include Acremonium coenophiulum, Streptomyces griseus, Trichoderma harzanium, T. viride, Rhodotorula glutinis, Paenibacillus polymyxa, Bacillus subtilis, B. megaterium, Pseudomonas putida, P. fluorescens compared with natural elicitors as methyl jasmonate (MJ), chitosan (CHI), ascorbic acid and putrescein (PUT). Varieties were planted in two progressive seasons in recently reclaimed lands, where two fields were selected the first is located in North Sinai while the second is situated to the south of Behira Governorate. Bio elicitors reduced abiotic stress and enhance physiological characteristic expressed as Proline, soluble carbohydrates %, Chl.a, Chl.b, Chl.a + b; Chl.a/Chl.b; Carotenoids and increased the concentration of Crude protein, N, P and total soluble carbohydrates in wheat grains. Using P. fluorescens exhibted increment in grain yield of wheat plants, cv sakha 93 amounted by 68.3% in Sinai region, while in Behira region the increement reached (45.5%) with P. polymyxa treatment. The response of Gemmiza 10 variety to the Bio-elicitors was less compared to Sakha 93 variety in both regions, where the highest increments due to P. putida treatment were18.9 and 19.7% in Sinai and beheirwa regions, respectively, compared to the control in each region. A remarkable increments of wheat growth, development and extended survival under salt and water limiting and restricting conditions. These findings demonstrate that wheat plants can display improved stress tolerance through bio-elicitors, and recommend that innovation may be useful in reducing effects of climate change and environmental stress on other crops and expanding agricultural production onto marginal lands.  相似文献   
2.
This study was carried out to assess the ability of using pawpaw (Carica papaya) seeds as a natural reproduction inhibitor for tilapia fish (Oreochromis niloticus) culture to control its breeding. Biochemical, physiological and histopathological effects ofpawpaw seeds on male tilapia fish were also determined. Mature male tilapia were stocked for 4 weeks and treated with low dose (3 g/kg/day) and high dose (6 g/kg/day) of ground dried pawpaw seeds mixed with their feed. The obtained results showed that the pawpaw seeds induced permanent sterility in the high dose treated fish while the low dose treatment showed reversible results. The results also demonstrated that fish treated with high dose of pawpaw exhibited higher biochemical and physiological effects as: low meat quality, a progressive fall in erythrocyte (RBCs) count, hemoglobin (Hb) content and haematocrit values. Also the high dose revealed a significant increase in the leukocytes (WBCs) count, serum glucose, total protein, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine and uric acid levels. Moreover, serum total lipids revealed a significant decrease compared to control group. On the other hand, the low dose treatment revealed lower biochemical and physiological changes. Histological sections of testis showed disintegration of sperm cells and focal necrosis of seminefrous tubules in the high dose treated fish, hepato-pancreas and posterior kidney tissues also showed severe changes in high dose treated fish. Milder degenerative changes in some necrotic foci and slight changes in hepato-pancreas and posterior kidney were observed in the low dose treated fish. The study concluded that pawpaw seeds which are cheap and easy to obtain, can be incorporated into fish feeds with adjusted amount and be used to control breeding of tilapia fish in growing ponds instead of unfavorable and expensive hormonal use.  相似文献   
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To test if locus-specific microsatellite markers designed for one genus are informative when used with related genera, the conservation of microsatellite-flanking intergeneric primer binding sites was tested in the closely related tribes Vicieae and Cicereae, from the subfamily Papilionoideae of the Leguminosae family. A total of 123 sequence-tagged microsatellite sites (STMS) markers derived from chickpea were used to amplify loci in lentil (Lens) and dry pea (Pisum). The percentage of chickpea primer binding sites conserved between the three genera was 54.4%. Hybridisation of 63 selected amplified loci to the digoxigenin-labelled oligonucleotide probe (TAA)5 showed that 69.8% of loci from dry pea and 66.6% of loci from lentil hybridised to the probe. Sequencing of amplified products from chickpea with the primer Ta176 demonstrated that one amplicon contained a microsatellite, whereas another amplicon amplified with the same particular STMS primer pair did not. Amplicons produced from lentil and pea with this primer pairs did not contain microsatellite sequences. Results obtained with Tr7, which amplified a PCR product in lentil and chickpea but not in pea, showed that microsatellite sequences were present in chickpea and absent in lentil. Similar results were obtained with Ts35, which produces amplicons in pea and chickpea; but, again, microsatellite sequences were only present in chickpea. We therefore conclude that STMS derived from chickpea could be used to detect variability between other Leguminosae genera, but it is necessary to verify whether homologous loci are revealed.  相似文献   
5.
Identifying barley genomic regions influencing the response of yield and its components to water deficits will aid in our understanding of the genetics of drought tolerance and the development of more drought tolerant cultivars. We assembled a population of 192 genotypes that represented landraces, old, and contemporary cultivars sampling key regions around the Mediterranean basin and the rest of Europe. The population was genotyped with a stratified set of 50 genomic and EST derived molecular markers, 49 of which were Simple Sequence Repeats (SSRs), which revealed an underlying population sub-structure that corresponded closely to the geographic regions in which the genotypes were grown. A more dense whole genome scan was generated by using Diversity Array Technology (DArT®) to generate 1130 biallelic markers for the population. The population was grown at two contrasting sites in each of seven Mediterranean countries for harvest 2004 and 2005 and grain yield data collected. Mean yield levels ranged from 0.3 to 6.2 t/ha, with highly significant genetic variation in low-yielding environments. Associations of yield with barley genomic regions were then detected by combining the DArT marker data with the yield data in mixed model analyses for the individual trials, followed by multiple regression of yield on markers to identify a multi-locus subset of significant markers/QTLs. QTLs exhibiting a pre-defined consistency across environments were detected in bins 4, 6, 6 and 7 on barley chromosomes 3H, 4H, 5H and 7H respectively.  相似文献   
6.
The present study was an investigation of the effect of the contraceptive drug, Nordette, on the stomach of the mouse when administered daily at a recommended therapeutic dose rate of 0.0026 mg kg(-1) for 30 days. Extensive light and electron microscopic changes were noticed. The drug caused enlargement in the all types of cells. The oxyntic cells appeared hypertrophied with irregular cell boundaries, enlarged nuclei and faintly stained cytoplasm. Their cytoplasm contained irregularly distributed mitochondria with dense matrix, decreased rER, obviously increased sER, disorganized intracellular canaliculi and some lysosomes. The peptic cells appeared enlarged and contained hypertrophied rough endoplasmic reticulum and an increase amount of ribosomes and secretory granules. There was an increase in the amount of the secretory granules in the lumen of the gastric gland. The mucus cells at the upper region of the gastric gland were greatly decreased. Smooth muscle fibers showed enlargement and degeneration. The submucosa and lamina propria showed vacuolation. The most pathological effects were restricted to the obvious decrease of the lymphoid cells in the submucosa and lamina propria. Dilatation and congestion of the blood vessels and blood capillaries were noticed. Blood capillaries lined by enlarged endothelial cells containing enlarged heterochromatic nuclei.  相似文献   
7.
Salinity is a major problem affecting crop production worldwide. The potential of different soil amendments (sulphur, gypsum, compost, and combination of gypsum, compost and sulphur) and two plant-growth stimulators (potassium silicate and calcium carbonate nanoparticles) to alleviate the harmful effects of saline soil on two cultivars of berseem clover (Trifolium alexandrinum L.), one salt tolerant (‘Serw-1’) and the other high yielding (‘Helaly’), was evaluated. Some soil properties were measured before and after treatments. Plant growth parameters, herbage yield, nutritive value and plant metabolites, including photosynthetic pigment and endogenous hormone contents, were also determined. The herbage yield of berseem clover cultivars substantially increased with the application of soil amendments in both years. The greatest yield increase was obtained with the compost application. The highest protein contents in herbage (16.4% in Helaly and 17.2% in Serw-1) were detected in response to composite (compost + gypsum + sulphur) and compost treatments, respectively. Carbohydrate content increased to 9.53% in Helaly and 5.1% in Serw-1 in response to the gypsum and compost treatments, respectively. The composite, compost and gypsum soil amendments were the most effective treatments resulting in the greatest herbage yield and quality values.  相似文献   
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The purification of raw surface water from its organic, inorganic and microbial content using the electro-coagulation method was investigated. Batch coagulation experiments were conducted using the jar-test method. A pair of aluminum electrodes (suspended in the jar) was charged with low voltage current for releasing aluminum ions in the raw water to precipitate the suspended matter. The optimum current density was 0.6325 mA cm–2. The coagulation efficiency was evaluated by determining the turbidity of treated water. The efficiency reduction in raw water turbidity was 90%, leading to a change in water Zeta potential from –85 mV (before treatment) to –40 mV (after treatment), i.e. the particles tended to be destabilized and the coagulation process became predominant. Water contents of nitrates, phosphates and sulfates were considerably reduced by 77.5, 83.3 and 20.0%, respectively. Also, this method is effective in reducing both the total viable bacterial count (TVBC) and total coliforms (TC) by a ratio of 1/104 and 1/103, respectively.  相似文献   
10.
Efforts are made to record biodiversity of microflora and diazotrophs associated with the plant cover of the major agricultural development areas in north Sinai, around the El-Salam canal, a newly-constructed canal that brings Nile water westward across the Suez canal. Natural plant communities were collected from three major areas. Ectorhizosphere, endorhizosphere and phyllosphere samples were examined for total microbial population and diazotrophs. The vegetation of South Qantara (area I) is characterized by the dominance of Stipagrostis scoparia followed by Nitraria retusa, Convolvulus lanatus, Cornulaca monacantha and Filago desertorum. Rabaa-Bir El Abd (area II) is dominated by Artemisia monosperma, Panicum turgidum and Zygophyllum album. Euphorbia terracina, Oligomeris linifolia, Astragalus kahiricus, Hyoscyamus muticus and Thymelea hirsuta represent the major plants of El Ser and Al Quarir (area III). Microorganisms colonized root surfaces of all tested plants ranging from >?105 to 1010 cfu g???1. Diazotrophs were common residents (1010 cfu g???1), invaded the root tissue and established endophytically (102?–?106 cfu g???1). Fifty-one N2-fixing isolates were obtained. Among the 32 bacilli isolates, Bacillus polymyxa and Bacillus circulans were more common compared to Bacillus macerans. BNF Gram-negative isolates belonged to Enterobacter agglomerans, Enterobacter gergoviae, Enterobacter amnigenus, Klebsiella pneumoniae, Pseudomonas luteola, Pseudomonas cepacia, Agrobacterium radiobacter and Azospirillum spp.  相似文献   
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