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1.
Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro‐ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (< .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (< .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics.  相似文献   
2.
Shade is one of the important limiting factors in intercropped agro-ecosystems. Objective of this work is to analyze the role of eight foliar traits of juvenile plants of five different species of Jasminum grown under coconut shade. The results reveal the shade tolerant J. pubescence to produce more number of nodes and longer shoots in all the three seasons studied. J. grandiflorum produced longer leaves and internodal distance than other species tested. Winter season shoots were longer with more number of nodes and longer internodal distances than rainy season. Results are discussed in relation to the adaptive behavior of plants to shade.  相似文献   
3.
Summary Two RAPD markers linked to gene for resistance (assayed as pustule number cm−2 leaf area) to rust [Uromyces fabae (Pers.) de Bary] in pea (Pisum sativum L.) were identified using a mapping population of 31 BC1F1 [HUVP 1 (HUVP 1 × FC 1] plants, FC 1 being the resistant parent. The analysis of genetics of rust resistance was based on the parents, F1, F2, BC1F1 and BC1F2 generations. Rust resistance in pea is of non-hypersensitive type; it appeared to be governed by a single partially dominant gene for which symbol Ruf is proposed. Further, this trait seems to be affected by some polygenes in addition to the proposed oligogene Ruf. A total of 614 decamer primers were used to survey the parental polymorphism with regard to DNA amplification by polymerase chain reaction. The primers that amplified polymorphic bands present in the resistant parent (FC 1) were used for bulked segregant analysis. Those markers that amplified consistently and differentially in the resistant and susceptible bulks were separately tested with the 31 BC1F1 individuals. Two RAPD makers, viz., SC10-82360 (primer, GCCGTGAAGT), and SCRI-711000 (primer, GTGGCGTAGT), flanking the rust resistance gene (Ruf) with a distance of 10.8 cM (0.097 rF and LOD of 5.05) and 24.5 cM (0.194 rF and a LOD of 2.72), respectively, were identified. These RAPD markers were not close enough to Ruf to allow a dependable maker-assisted selection for rust resistance. However, if the two makers flanking Ruf were used together, the effectiveness of MAS would be improved considerably.  相似文献   
4.
A rich genetic diversity of coconut exists in farmer's fields, which represent valuable genetic resource for breeding. The study was conducted to assess the pattern of diversity in 102 coconut palms representing 10 landraces from 3 coconut-growing communities of India using 14 simple sequence repeat (SSR) markers. A total of 90 alleles were detected with an average of 6.42 alleles per locus and an average polymorphism information content of 0.61. Expected heterozygosity (He) was highest for the two tall landraces from Pallikkara community, while the least heterozygosity was observed for the dwarf coconut landraces from Vayalar community. Mean fixation index (FST) of 0.42 indicates a high level of population differentiation. A low gene flow (Nm) of 0.37 was observed. Based on molecular data, genetic similarities were calculated. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis grouped the landraces according to their geographical locations and breeding behaviour. The practical implications of this study in farmer participatory evaluation and conservation of coconut genetic resources are highlighted.  相似文献   
5.
The health of the pond environment in shrimp farming is important for sustainable and profitable aquaculture, in which sediment–water interface is the most important influencing area. With this objective, the key parameters of water and sediment at the interface was studied in shrimp ponds with varying salinities and compared with the surface water and soil to understand the variations and the underlying causes. Total ammonia nitrogen and total alkalinity were higher in water at the interface as compared to surface water, whereas pH, nitrite, oxide forms of nitrogen (NO3), phosphorus (PO4) and oxidizing bacteria were observed to be lower. There was no significant difference with respect to macrominerals such as sodium, potassium, calcium and magnesium between water at the interface and surface. These changes are profoundly influenced by the uppermost 1.0‐cm thick sediment layer, where the maximum transition of nutrients takes place with the water column. The outcome of the study highlights the effectiveness of water sampling for metabolites at the interface, which reflects at an early stage any potential deterioration of pond environment, which will help the farmer to initiate timely mitigation measures.  相似文献   
6.
Noni (Morinda citrifolia L.) or Indian mulberry is an evergreen tree species of coastal tropics and has several uses as herbal medicine, cosmetic, vegetable, animal feed, dye and timber. It is a storehouse of useful phytochemicals including caprylic acid, damnacanthal, lineolic acid, morindine, octonic acid and xeronine. The species is hardy, tolerant to shade and salinity hence suitable for marginal lands of tropical coastal ecosystem. Nineteen accessions of noni were collected across the Konkan coast of Goa and Maharashtra states of western India. They are conserved in Indian National Gene Bank assigned with national identity as indigenous collection (IC) numbers viz., IC 0595272 to IC 0595277; IC 0598228 to IC 0598231; IC 0598515 to IC 0598516; IC 0598232 to IC 0598235; IC 0612951 to IC 0612953. The field grown germplasm accessions were characterised using quantitative traits of stem, leaf, flower, fruit and seeds. High degree of variation was recorded for fruit weight and number of seeds per fruit. The results are discussed in the light of evolution, dispersal and utilization. This report aims to summarize the various reports on uses, composition of phytochemcials, and diversity of noni to harness its utilization by increasing human inhabitants in tropical coastal lands.  相似文献   
7.
Understanding the physiology of dry-matter accumulation and nutrient uptake pattern of an onion crop is an essential criteria for optimizing fertilizer practices. An experiment was conducted to estimate the dry-matter accumulation and nutrient uptake pattern of short day onion. The dry-matter accumulation and nutrient uptake followed the sigmoid growth curve pattern. Uptake of nitrogen and potassium was slow for the first 15 days followed by rapid uptake from 15 to 60 days after transplanting and accounted for 76.2–78.2% of total uptake. Takeup of phosphorus, sulfur, manganese, zinc, and copper uptake was greater during 30 to 75 days after transplanting and accounted for 64.9–70.6% of total uptake. The deficiency of nutrients during these period reduces the crop yield significantly. The dry-matter accumulation and nutrient-uptake pattern reported in this study provide an opportunity for optimizing quantity and timing of nutrient application through fertilizers for short day onions.  相似文献   
8.
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species (Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea, Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content, lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature, and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling.  相似文献   
9.
Bovine interleukin 2: biochemical and biological characterization   总被引:1,自引:0,他引:1  
Interleukin 2 (IL-2), secreted by bovine peripheral blood mononuclear cells (PBL) on stimulation with concanavalin A (Con A), was purified and characterized by different chromatographic and electrophoretic techniques. The ability of IL-2 to support proliferation of Con A-stimulated bovine lymphoblasts was used to assay and quantitate IL-2 activity. Bovine IL-2 having an apparent MW of 27,000 eluted from a gel-filtration column; from an anion exchange column peak activity was detected at 190 mM NaCl. Binding of bovine IL-2 to phenyl-Sepharose gel and elution with 35-60% ethanediol indicated its hydrophobic nature. Studies on cross-species reactivity revealed that both buffalo and goat lymphocytes respond to cattle IL-2 and detected 35% of activity from a standard cattle IL-2 preparation. Sheep lymphocyte response to cattle IL-2 was negligible.  相似文献   
10.
An extracellular chitinase was purified from Bacillus subtilis. The lethal concentration (LC50) was determined by using chitinase in first, second, and third instars of Spodoptera litura Fab. Chitinase showed the highest insecticidal activity at 6 μM concentration within 48 h. The nutritional indices were also significantly affected by the 6 μM concentration (P < 0.05). Food consumption, efficiency of conversion of ingested and digested food, relative growth rate, and consumption values declined significantly while approximate digestibility was increased. Our study indicates that treatment of host plant leaves with the chitinase can regulate (reduce) larval growth and weight, and enhance the mortality. This may serve as an effective biocide and alternative to Bt toxin.  相似文献   
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