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31.
Tropical Animal Health and Production - Camel is an important domestic animal that is well adapted to extremely harsh environments. Due to its multi-purpose role, the camel is gaining importance,...  相似文献   
32.
To determine the seroprevalence of Borrelia burgdorferi antibodies in horses in Minnesota, the database of the Veterinary Diagnostic Laboratory, University of Minnesota, was searched over a 10-year period (May 2001 to May 2010). A total of 1,260 equine serum samples submitted by 112 veterinary clinics were tested using an indirect fluorescent antibody test. Samples with titers of ≥1:320 were considered positive. The average rate of seroprevalence was 58.7%, indicating high exposure of horses to B burgdorferi in Minnesota. Our results indicate that borreliosis should be considered as a differential in cases of horses with undiagnosed musculoskeletal or neurologic disease.  相似文献   
33.
ABSTRACT

Glyphosate-resistant (GR) weeds are the biggest concern for all cotton stakeholders worldwide. Currently, 43 weeds species are resistant to glyphosate and the number is increasing at an alarming rate. Soil residual/pre-emergence (PRE) herbicides like Pendimethalin and S-metolachlor can be effectively used for the control of GR weeds; however, their use is very limited at farmer’s side due to the adoption of herbicide-tolerant technology with complete reliance on glyphosate. The present study was conducted to evaluate the performance of PRE and post-emergence (POST) herbicides in glyphosate-tolerant (GT) cotton. The herbicide treatments were pendimethalin and S-metolachlor as PRE-residual, and glyphosate was applied as POST at 20 days after sowing (DAS) either alone or in combination with other herbicides like S-metolachlor, pendimethalin, and haloxyfop. A second application of glyphosate was made at 35 DAS. Results revealed that pendimethalin and S-metolachlor treatments gave 100% suppression of all dominant weeds and increased lint yield by 310–350% as compared to weedy control. In contrast, glyphosate applied once and twice, gave weed biomass reduction of only 10–86%, and increased lint yield by 136–185% over weedy control. This research established that PRE application of pendimethalin and S-metolachlor can be included in the weed management program of GT cotton.  相似文献   
34.
Sodium alginate is a polysaccharide that is largely obtained from the brown algae (Sargassum sp.).It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate (ISA),viz.,deionized water (control,T0),20 (T1),40 (T2),60 (T3),80 (T4),and 100 ppm (T5) on the agricultural performance of Catharanthus roseus L.(Rosea) in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.  相似文献   
35.
Artemisinin, a sesquiterpene lactone with a peroxide linkage, has been held responsible for antimalarial activity of the Artemisia annua L. Recently, it was reported that reactive oxygen species (ROS) play important role in the biosynthesis of artemisinin by catalyzing some important intermediate steps. The effect of exogenously supplied hydrogen peroxide (1.00 mM and 2.00 mM H2O2), in two ways, foliar and as soil drench, was worked out in terms of growth, alteration in photosynthesis, oxidative damage, antioxidant defense enzymes and artemisinin level in exposed plants. Application of H2O2 positively affect the growth of the treated plants; and increment in net photo synthetic rate, stomatal conductance, internal CO2 and chlorophyll content in the H2O2 exposed A. annua plants was noted. A significant upregulation in antioxidant enzymes viz. catalase (CAT), peroxidase (POX) and superoxide dismutase (SOD) was observed as a result of exogenous H2O2 treatment when applied foliarly or as soil drench. H2O2application either by 1.00 mM or 2.00 mM stimulated artemisinin levels, however, 2.00 mM H2O2 applied as soil drench elicited artemisinin production more rapidly compared to other treatments. Therefore, results suggest that exogenous H2O2 may stimulate growth by inducing antioxidant defense system and increase the artemisinin levels in Artemisia annua plants.  相似文献   
36.
A pot experiment was conducted to find out whether the foliar spray of salicylic acid (SA) could successfully ameliorate the adverse effects of water stress on periwinkle. Pots were irrigated with ground water regularly as a control and other treatments were given as 15 and 30 days interval drought (DID) at 30 DAS. Plants were uprooted randomly at 46 and 61 DAS, washed carefully and separated into root, stem and leaf for analyses. A uniform concentration (10−5 mol/l) of salicylic acid (SA) was applied as a foliar spray at the vegetative stage. Water stress significantly reduced the growth attributes including plant height, leaf-area index, shoot and root fresh weights, shoot and root dry weights. Long term water stress led to a gradual decrease in photosynthetic parameters and activities of nitrate reductase and carbonic anhydrase. Ascorbic acid, total alkaloids and antioxidant enzymes: superoxide dismutase, catalase and peroxidase increased in stress faced plants. Foliar application of SA (10−5 M) reduced the damaging effect of stress on plant growth and accelerated the restoration of growth processes. It not only improved the growth parameters but also partially reversed the effects of salinity. Total alkaloid content was improved by SA application both in unstressed and stressed plants. Foliar spray of SA not only overcame the adverse effect of stress but also improved the content of vincristine and vinblastine in stressed plants.  相似文献   
37.
Water, Air, & Soil Pollution - Different bases were used for the pretreatment of Rice bran biomass. Pretreatment with bases such as NaOH, Ca(OH)2 and Al(OH)3 were found to improve biosorption...  相似文献   
38.
A wide gap exists between production and consumption of vegetable oils in Pakistan. Thereby, a significant proportion (2.28 million tons) of vegetable oils is being imported at the cost of 2257 million US$. Therefore, the present study was conducted to quantify the comparative performance of various sunflower hybrids as influenced by various levels of nitrogen (N) fertilizer under different agro-environments. The experimental treatments consisted of three sunflower hybrids (Hysun33, Hysun38, and Pioneer-64A93) and five levels of N fertilizer (0, 60, 120, 180, 240 kg N ha?1), arranged in a randomized complete block design in a split plot with four replications. The field trials were conducted for two consecutive crop seasons under three different agro-ecologies (arid, semi-arid, and sub-humid) in the province of Punjab, Pakistan. The results of the study demonstrated that the productivity of sunflower hybrids varied greatly in response to N fertilization and different ecologies. Maximum achene yield of 3177 kg ha?1 was harvested under sub-humid environment, followed by the semi-arid one. Among the hybrids, Hysun38 excelled the other two hybrids with a production of 3083 kg ha?1 and 41% oil contents. Generally, the productivity of hybrids increased with the increasing doses of N fertilizer. Maximum achene yield was obtained by addition of 180 kg N ha?1. The findings of the study revealed that yield potential of Hysun-38 could be exploited by addition of N fertilizer at the rate of 180 kg N ha?1 under sub-humid environment.  相似文献   
39.
The experiment containing three replicates of completely randomized factorial treatments was conducted in a glasshouse under controlled conditions with three simulated soil salinity levels (control, 10 and 15 dS m?1). Morpho-physiological traits (i.e. lengths, fresh weights and dry weights of root and shoot, number of leaves, root/shoot ratio, shoot Na+ accumulation, K+/Na+ ratio, Ca2+/Na+ ratio, membrane stability index, lycopene contents, chlorophyll-a and -b) were recorded to determine mechanism of salt tolerance of tomato at seedling stage. Principal component analysis (PCA) was used to express a three-way interaction of genotype × salinity level × traits that scattered the 25 tomato genotypes based on their morpho-physiological response to different NaCl levels. The negative association of Na+ with all other traits except root/shoot ratio and the morpho-physiological response trend of genotypes exposed that probable mechanism of salt tolerance was initially Na+ exclusion by abscising older leaves to have younger physiologically energetic, and lastly a higher activity of plants for root development to sustain them in saline soil. PCA three-way biplot efficiently recognized ANAHU, LA-2821, LO-2752, LO-2707, PB-017909, LO-2831-23 and 017860 as salt tolerant genotypes. On the other hand, ZARNITZA, GLACIER, LO-2692, LO-2576, BL-1079, 006233, 006232, 017856, NUTYT-701 and NAGINA were found to be salt susceptible.  相似文献   
40.
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