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71.
The nodulation ability was determined of native Frankia strains (ChI1, ReI4, ReI6, TtI42, and TqI15) isolated from rhamnaceous species indigenous to Chile. All strains tested nodulated other Rhamnaceae host species within one or more genera, i.e., TtI42 nodulated seedlings of Trevoa trinervis, Retanilla ephedra, and Talguenea quinquenervia. Trees from other families such as Casuarina (Casuarinaceae) were not nodulated by the Frankia strains mentioned above. These results suggest that the five strains isolated from rhamnales could belong to the same cross inoculation group because they exhibited the same level of promiscuity. The effectivity of Frankia for nitrogen fixation was established by measurement of acetylene reduction activity in planta. Two strains (ReI6 and TtI42) were found more effective than the others and improved the total dry weight and shoot height of Retanilla ephedra seedlings. These studies may facilitate the choice of selected rhamnaceous Frankia pairs for arid soil afforestation, since these plants are naturally adapted to this environment in Chile. 相似文献
72.
Jos ngel Padilla Esther Sansinforiano Juan Carlos Parejo Araceli Rabasco Margarita Martínez-Trancn 《Livestock Science》2009,122(2-3):314-322
Blanca Cacereña cattle is the most threatened Spanish bovine breed. Although a Conservation Plan, exists, the little reproductive success and some chromosome abnormality were observed in the breed making it advisable to extend the genetic basis of the animals opening up the recorded herd book to new animals from local farms. However, the crossing with meat breeds like Charolais cattle is used to improve the commercial product. We used 30 microsatellites to determine the Charolais genetic influence in the current herds by the identification of the hybrids and to recognize new “purebred” animals in the “Blanca Cacereña” population. Blood samples were taken from animals of Blanca Cacereña bovine breed (112 animals with pedigree and 68 without pedigree), Charolais breed (60 animals) as a breed used commercially in crosses with Blanca Cacereña, and Retinta breed (60 animals) as a reference population. STRUCTURE analyses were performed with or without prior population information to assign individuals to breed, identifying admixed individuals, and inferring their ancestry. We have found that 37/68 animals without pedigree were purebred. Our results will be useful to manage a conservation plan of the breed, preserving the characteristic genetic pool and avoiding its extinction. 相似文献
73.
Andrea Rodríguez Blanco Margarita Sicardi Lillian Frioni 《Biology and Fertility of Soils》2010,46(4):419-425
The aim of this work was to evaluate the competitive ability between Rhizobium leguminosarum bv trifolii strain U204 used as commercial inoculants in Uruguay for Trifolium repens L. and Trifolium pratense L. and two native strains isolated from inoculated pastures of T. pratense. T126 is an efficient nitrogen fixer and a melanin producer strain; T70 is inefficient and a melanin non-producer strain;
and U204 is very efficient in both hosts but is a melanin non-producer strain. Competitiveness between the strains was determined
in experiments in pots and in growth pouches under controlled conditions. In the last experiment, we evaluated pH of plant
nutrient solution and inoculum ratios. Plant dry weight was determined, and the identification of nodule bacteria was done
using melanin production and DNA fingerprinting (GTG5-PCR). The U204 symbiotic efficiency was not affected by the co-inoculation with the others two native strains. The T70 strain
was a poor competitor when was co-inoculated with one of the effective strains in both experiments. Our results confirmed
a “selective nodulation” because an effective symbiosis occurred preferentially over an ineffective one in Trifolium species. The native effective strain competed with U204 for nodule formation in both clovers species, but the nodule occupancy
depended on the inoculum ratio. The pH of nutritive solution did not affect competition ability of the studied strains. It
may be possible to isolate efficient, competitive, and genetically different native rhizobial strains to be used as inoculant
strains for clover pastures in Uruguay. Both (GTG)5-PCR and melanin production were useful methods to identify nodulating bacteria in competition studies. 相似文献
74.
Margarita Mauro-Herrera Alan W. Meerow Lalith Perera Joanne Russell Raymond J. Schnell 《Genetic Resources and Crop Evolution》2010,57(2):203-217
A prior analysis of eight coconut cultivars with 15 microsatellite (SSR) markers drew unexpected relationships between two
of the out-crossing tall cultivars evaluated: ‘Atlantic Tall’ and ‘Panama Tall’. We further investigated the relationships
between these eight cultivars by increasing the number of individuals studied (particularly for ‘Atlantic Tall’ and ‘Panama
Tall’), by including 28 more molecular markers, and by adding two other cultivars to our analysis. Our results show that five
to ten coconut individuals do not represent a dependable sample to withdraw conclusions regarding cultivar/variety relationships,
particularly when studying out-crossing genotypes. As suggested in the prior study, a high level of hybridization was observed
between the ‘Atlantic Tall’ and ‘Panama Tall’ cultivars. However, at this time we were able to identify distinct groups for
each one of these two cultivars. The two clustering methods used (Neighbor Joining, NJ and Unweighted Pair Group Method with
Arithmetic mean, UPGMA) produced dendrograms that resolved contrasting cultivar relationships, especially for the ‘Atlantic
Tall’ and ‘Panama Tall’ cultivars. We discuss the implications of our results in regard to current scenarios of coconut domestication
and future considerations when assessing genetic relationships among different varieties. 相似文献
75.
Extracts, fractions and constituents of Carthamus lanatus were tested for their mitogenic effect on bone marrow cells in mice. Most of the studied samples inhibited cell proliferation and only the flavonoid glycoside rutin caused increasing of mitotic activity. 相似文献
76.
Pedro Ximenez sweet wines obtained following the typical criaderas and solera method for sherry wines and subjected to oxidative aging for 0, 1.3, 4.2, 7.0, or 11.5 years were studied in terms of color and aroma fraction by using the CIELab method and gas chromatography, respectively. The parameters defining the CIELab color space (a*, b*, and L*) were subjected to a multiple-range test (p<0.05) that allowed discrimination of the five wine aging levels studied into five uniform groups according to aging time. The aroma fraction was found to include 15 active odorant compounds with OAV > 1 that enriched the wines with fruity, fatty, floral, and balsamic notes during the aging process. The changes in color parameters and active odorants were not linearly related to aging time, being especially marked during the first 1.3 years and then less substantial up to the 7 years, the oldest wines exhibiting sensorial properties markedly departing from all others. For the wines aged over 1.3 years (minimum aging), 2,3-butanedione, linalool, and decanal can be used as reliable fingerprints of the older wines' quality. 相似文献
77.
78.
A. Paula Rodiño Margarita Lema Marlene Pérez-Barbeito Marta Santalla Antonio M. De Ron 《Euphytica》2007,155(1-2):63-70
The runner bean requires moderately high temperatures for optimum germination and growth. Low temperature at sowing delays
both germination and plant emergence, and can reduce establishment of beans planted early in the growing season. The objective
of this work was to identify potential runner bean germplasm with tolerance to low temperature and to assess the role of this
germplasm for production and breeding. Seeds of 33 runner bean accessions were germinated in a climate-controlled chamber
at optimal (17°C-day/15°C-night) and at sub-optimal (14°C-day/8°C-night) temperature. The low temperature tolerance was evaluated
on the basis of germination, earliness, ability to grow and vigor. Differences in agronomical characters were significant
at low temperatures for germination, earliness, ability to grow and early vigor except for emergence score. The commercial
cultivars Painted Lady Bi-color, Scarlet Emperor, the Rwanda cultivar NI-15c, and the Spanish cultivars PHA-0013, PHA-0133,
PHA-0311, PHA-0664, and PHA-1025 had the best performance under cold conditions. 相似文献
79.
Margarita Ros Maria Teresa HernandezCarlos Garc?&#x;a 《Soil biology & biochemistry》2003,35(3):463-469
Unsuitable agricultural practices together with adverse environmental conditions have led to degradation of soil in many Mediterranean areas. One method for recovering degraded soils in semiarid regions, is to add organic matter in order to improve soil characteristics, thereby enhancing biogeochemical nutrient cycles. In this study, the effect of adding the organic fraction of urban wastes (both fresh and composted) on different carbon fractions and on microbiological and biochemical parameters (microbial biomass C, basal respiration and different enzymatic activities) of a degraded soil of SE Spain has been assessed in a 2 year experiment. Three months after the addition of the organic material, spontaneous plant growth occurred and the plant cover lasted until the end of the experiment. Organic soil amendment initially increased the levels of soil organic matter, microbial biomass, basal respiration and some enzyme activities related to the C and N cycles These values decreased but always remained higher than those of the unamended soil. The results indicate that the addition of urban organic waste is beneficial for recovering degraded soils, the microbial activity of which clearly increases with amendment. The incorporation of compost seemed to have a greater positive effect on the soil characteristics studied than the incorporation of fresh organic matter. 相似文献
80.
Claudia Delgadillo-Puga Bernardo Sánchez-Muñoz José Nahed-Toral Mario Cuchillo-Hilario Margarita Díaz-Martínez Roman Solis-Zabaleta Aurora Reyes-Hernández Rosa Maria Castillo-Domíguez 《Tropical animal health and production》2014,46(5):883-888
Organic agriculture and livestock farming is claimed to promote animal welfare and can offer animal products with better hygienic-sanitary quality, based on principles of health, ecology, fairness, and care. However, no clear advantages of organic milk (OM) versus conventional milk (CM) from tropical conditions are available. The aims of the study were to determine fatty acid profile, health-promoting (HPI) and thrombogenic (TI) indices, physicochemical composition, and somatic cell counts (SCC) of OM and CM in tropical south-eastern Mexico. Female cross-breed cows (400–600 kg) were employed. CM had larger values of saturated fatty acids (SFA) and polyunsaturated fatty acid (PUFA) (63.6 %; 4.57 %) than OM (61.48 %; 4.22 %), while OM resulted in a larger value of monounsaturated fatty acid (MUFA) (34.3 %) than CM (31.7 %). HPI and TI showed that OM was more favorable than CM. Milk production and physicochemical composition (PC) as well as density had no significant difference, while SCC was significantly lower in OM than in CM on a monthly basis. These results showed that OM promotes a healthful and balanced diet, and is already produced by sustainable ecologic technologies employing traditional agrosilvopastoral management, which is more environmentally friendly and promotes ecological resilience. 相似文献