Features of transition of perennial grasses with adaptive Triticum-type proteins into anabiosis     

A. S. Timoshchenko  V. F. Semikhov  L. O. Nurminskaya  P. N. Kharchenko 《Russian Agricultural Sciences》2014,40(1):1-4

During 1–7-day stages of ontogenesis (for example, in winter rye), biochemical changes in the aerial part of perennial grasses with adaptive Triticum-type proteins in the process of entering into the state of anabiosis were studied. It was shown that, at this point, biomass of the aerial part of plant was much higher than of the root system, and it accumulated raffinose, sucrose, glucose, and half-cystine. Synthesis of raffinose and accumulation of half-cystine continued until the stabilization of negative temperatures; as for sucrose and glucose, it ceased upon reaching the average temperature of the physiological zero, then the content of half-cystine and raffinose increased sharply, and the content of sucrose and glucose decreased at the same time. In the aerial parts of plants, fructose and phenylalanine were found, and their content increased upon reaching freezing temperatures. It was concluded that the polymerization of water-soluble proteins occurred in perennial grasses in a state of anabiosis. These proteins, along with raffinose, serve as cryoprotectants; sucrose and glucose are substrates for respiration; fructose is a substrate for respiration and protective metabolite; and phenylalanine is a substrate for the future synthesis of antioxidants.  相似文献   

Application of complex compost in the course of winter wheat cultivation     

I. S. Belyuchenko  O. A. Mel’nik 《Russian Agricultural Sciences》2014,40(4):264-266

Influence of complex compost on the agronomical properties of soil, winter wheat development and productivity, and quality of production in the conditions of a farm located in the Leningrad area of Krasnodar territory was considered. The positive action of the complex compost on these indicators was noted.  相似文献   

Therapeutic effects of anthelmintic agents with ribotan immunomodulation     

O. I. Mamykova 《Russian Agricultural Sciences》2014,40(4):291-294

It has been established that the therapeutic efficacy of anthelmintic agents (fenbendazole, Nilverm) in combination with Ribotan depends on the dose of the immunomodulator. Administration of Ribotan in a dose of 0.05 mL/kg of body weight increased nonspecific resistance to invasion and enhanced the anthelmintic action of fenbendazole and Nilverm. Ribotan in a dose of 0.5 mL/mg has a negative effect on the result of specific treatment of mice infected by Aspiculuris tetraptera.  相似文献   

Leaf physiology and morphology of Castanea dentata (Marsh.) Borkh., Castanea mollissima Blume,and three backcross breeding generations planted in the southern Appalachians,USA     

Benjamin O. Knapp  G. Geoff Wang  Stacy L. Clark  Lauren S. Pile  Scott E. Schlarbaum 《New Forests》2014,45(2):283-293

Backcross breeding programs have been used to transfer disease resistance and other traits from one forest tree species to another in order to meet restoration objectives. Evaluating the field performance of such material is critical for determining the success of breeding programs. In eastern North America, The American Chestnut Foundation has a backcross breeding program that uses Chinese chestnut (Castanea mollissima Blume) to introduce resistance of the fungal pathogen chestnut blight [Cryphonectria parasitica (Murr.) Barr.] to the native American chestnut [Castanea dentata (Marsh.) Borkh.]. We compared physiological and morphological characteristics among seedlings of American chestnut, Chinese chestnut, and BC₁F₃, BC₂F₃, and BC₃F₃ hybrid chestnuts during their fourth growing season after field-planting. American chestnut and the BC₃F₃ breeding generation displayed photosynthetic light-response curves that were similar to each other but different from Chinese chestnut. Rates of photosynthesis were higher for American chestnut and the BC₃F₃ breeding generation when compared to Chinese chestnut for light levels ≥800 μmol m^?2 s^?1 photosynthetic photon flux density and for maximum photosynthetic capacity. Leaf morphology variables were not different between American chestnut and any of the breeding generations, but leaf area (on a per leaf basis) of Chinese chestnut was lower than that of any other chestnut type. Our results suggest that backcross breeding can be used to transfer desirable traits for restoration of native species threatened by non-native pathogens.  相似文献   

Evaluating changes in switchgrass physiology,biomass, and light-use efficiency under artificial shade to estimate yields if intercropped with Pinus taeda L.     

Janine M. Albaugh  Timothy J. Albaugh  Ryan R. Heiderman  Zakiya Leggett  Jose L. Stape  Kyle King  Katherine P. O’Neill  John S. King 《Agroforestry Systems》2014,88(3):489-503

There is growing interest in using switchgrass (Panicum virgatum L.) as a biofuel intercrop in forestry systems. However, there are limited data on the longevity of intercropped bioenergy crops, particularly with respect to light availability as the overstory tree canopy matures. Therefore, we conducted a greenhouse study to determine the effects of shading on switchgrass growth. Four treatments, each with different photosynthetically active radiation (PAR) levels, were investigated inside the greenhouse: control (no shade cloth, 49 % of full sunlight), low (under 36 % shade cloth), medium (under 52 % shade cloth), and heavy shade (under 78 % shade cloth). We determined the effect of shading from March to October 2011 on individually potted, multi-tillered switchgrass transplants cut to a stubble height of 10 cm. In the greenhouse, there was a reduction in tiller number, tiller height, gas exchange rates (photosynthesis and stomatal conductance), leaf area, above- and belowground biomass and light-use efficiency with increasing shade. Total (above- and belowground) biomass in the control measured 374 ± 22 compared to 9 ± 2 g pot^?1 under heavy shade (11 % of full sunlight). Corresponding light-use efficiencies were 3.7 ± 0.2 and 1.4 ± 0.2 g MJ^?1, respectively. We also compared PAR levels and associated aboveground switchgrass biomass from inside the greenhouse to PAR levels in the inter-row regions of a range of loblolly pine (Pinus taeda L.) stands from across the southeastern United States (U.S.) to estimate when light may limit the growth of intercropped species under field conditions. Results from the light environment of loblolly pine plantations in the field suggest that switchgrass biomass will be significantly reduced at a loblolly pine leaf area index between 1.95 and 2.25, which occurs on average between ages 6 and 8 years across the U.S. Southeast in intensively managed pine plantations. These leaf area indices correspond to a 60–65 % reduction in PAR from open sky.  相似文献   

On the magnitude and dynamics of eddy covariance system residual energy (energy balance closure error) in subsurface drip-irrigated maize field during growing and non-growing (dormant) seasons     

Suat Irmak  Jose O. Payero  Ayse Kilic  Lameck O. Odhiambo  Daran Rudnick  Vivek Sharma  David Billesbach 《Irrigation Science》2014,32(6):471-483

We investigated the magnitude and dynamics of the eddy covariance system (ECS) residual energy (energy balance closure error) for a subsurface drip-irrigated maize (Zea mays L.) field in 2005 and 2006 growing and non-growing (dormant) seasons. The corrections for coordinate rotation, oxygen, frequency, and Webb–Pearman–Leuning corrections improved the slope of the total convective energy (latent heat + sensible heat) with respect to the net available energy (from 0.68 to 0.84), but the data filtering (for horizontal and frictional wind speeds higher than 2 m s^?1 and lower than 0.2 m s^?1) had little effect on the slope. Also, the number of data points available for the analyses was reduced by 53 % after filtering. Overall, the daytime residual energy varied between ?100 and 200 W m^?2 during the dormant seasons and between ?500 and 600 W m^?2 during the growing seasons. Most of the nighttime residual energy ranged within ±40 W m^?2 during the calendar year in 2005 and within ?60 and 20 W m^?2 in 2006. During nighttime, the total convective energy is vertically distributed with respect to (R _n ? G), indicating that the total convective energy is independent of the variations in (R _n ? G). Secondly, it was observed that nighttime residual energy did not show any seasonal variation patterns throughout the two consecutive years and confined mostly within a narrow range of ±40 W m^?2, showing no dependency on seasonal changes in surface conditions. The maximum variation in residual energy was usually around frictional wind speed of 0.3–0.5 m s^?1 (varying between ?150 and 300 W m^?2) and then decreasing to a range of ±100 W m^?2 at higher frictional wind speeds. On average, the residual energy decreased by about 33 W m^?2 (after the intercept) for every 1.0 m s^?1 increase in frictional wind speed, whereas the residual energy decreased by about 4 W m^?2 (after the intercept) for every 1.0 m s^?1 increase in horizontal wind speed. Similar diurnal residual energy distribution patterns, with different magnitudes, were observed during growing and dormant seasons. Even though a slight decrease in residual energy was observed with increase in leaf area index (LAI) in both growing seasons, LAI did not have considerable influence on the seasonal variation in the residual energy. The residual energy was also evaluated by separating the data into morning and afternoon hours. We observed that the root-mean-squared difference value is slightly greater for the morning data than the afternoon, indicating greater residual energy in the morning hours due to weaker turbulent mixing than the afternoon. Overall, significant reduction in the available evapotranspiration data after applying a series of corrections possess challenges in terms of utilization of ECS for in-season irrigation management and crop water requirement determinations that needs to be further researched and addressed.  相似文献   

Digestive enzyme activity during early larval development of the Cuban gar Atractosteus tristoechus   总被引：1，自引：0，他引：1  

Y. Comabella  R. Mendoza  C. Aguilera  O. Carrillo  A. Hurtado  T. García-Galano 《Fish physiology and biochemistry》2006,32(2):147-157

The ontogenesis of digestive enzymes (proteases, amylases, lipases, and phosphatases) in Cuban gar Atractosteus tristoechus was determined in larvae between 5 and 18 days after hatching (DAH). Variations in specific activities of most enzymes were related to the transition from endogenous to exogenous feeding and to the transition from the larval to the juvenile stage. Alkaline protease activity was not detected until 8 DAH in contrast to acid protease activity, which was quantifiable at 5 DAH. Acid protease activity was consistently higher than alkaline protease activity, indicating the presence of a functional stomach in the early stages of larval development. The acid protease activities of larvae and adults were compared by means of zymogram analysis. Four acid protease bands were found in adults (two more than in larvae). This result is the first time that more than one band of acid proteolytic activity has been found in Lepisosteidae. High lipase activity indicated the importance of lipid utilization, particularly during yolk-sac absorption. In contrast to the other enzymes studied, amylase activity was consistently low, probably due to the strictly carnivorous diet of gar larvae and their low capacity for carbohydrate digestion. High activities of aminopeptidase and acid and alkaline phosphatases suggest intestinal absorption. This result, together with the existence of a short gut and a lower proteolytic activity in the intestine than in the stomach, suggest that most of the proteolytic activity takes place in the stomach, while the primary function of the intestine is nutrient uptake.  相似文献   

Dietary protein/energy ratios for Atlantic salmon in relation to fish size: growth, feed utilization and slaughter quality   总被引：3，自引：0，他引：3  

O. Einen  & A. J. Roem 《Aquaculture Nutrition》1997,3(2):115-126

Four extruded diets differing in protein/fat concentrations, 378/389 g kg^?1, 425/346 g kg^?1, 480/308 g kg^?1 and 524/256 g kg^?1 were tested in a digestibility trial and a growth study. Apparent digestibility of protein and fat were not significantly different among the diets when tested in 1-kg Atlantic salmon, Salmo salar L., in sea water. The diets represented a range of digestible protein to digestible energy ratios (DP/DE ratios) of 14.1, 16.4, 18.8 and 21.9 g MJ^?1. The 138-day growth study was performed with triplicate groups of Atlantic salmon of 1.0 and 2.5 kg initial weight. Irrespective of size; growth, feed conversion ratio (FCR), nitrogen and energy retention were poorer in fish fed the diet with DP/DE ratio of 14.1 g MJ^?1 compared with the fish fed the other diets. A DP/DE ratio of 16.4 g MJ^?1 was sufficient to produce maximum growth for the large fish, while the DP/DE ratio of 18.8 g MJ^?1 produced the highest growth in the small fish. In the large fish, the lowest FCR was obtained on a DP/DE ratio of 16.4 g MJ^?1, while there was no clear difference in FCR within the small fish when diets of DP/DE ratios of 16.4–21.9 g MJ^?1 were fed. The carcass-to-body ratio in the small fish decreased with decreasing DP/DE ratios. The fish fed the diet of 21.9 g MJ^?1 had significantly lower fat and dry matter and higher protein content than fish of similar size fed the other diets. Increased dietary lipid content seemed to improve astaxanthin deposition in the small fish, while the large fish showed no significant differences in astaxanthin deposition due to dietary treatment. This study indicates that a DP/DE ratio of 14.1 g MJ^?1 in high-energy diets for Atlantic salmon in sea water is below the optimal DP/DE ratio for growth and feed utilization, and that the optimal DP/DE ratio decreases with increasing fish weight. DP/DE ratios around 19 g MJ^?1 for fish weighing 1 to 2.5 kg, and 16–17 g MJ^?1 for fish weighing 2.5 to 5 kg, are suggested to be optimal.  相似文献   

Antibody-coated gold nanoparticles immunoassay for direct detection of Aeromonas salmonicida in fish tissues     

Saleh M  Soliman H  Haenen O  El-Matbouli M 《Journal of fish diseases》2011,34(11):845-852

Aeromonas salmonicida is the causative agent of furunculosis, a disease that affects both salmonid and non‐salmonid fish. Detection of A. salmonicida can be labour intensive and time consuming because of the difficulties in distinguishing the bacterium from other species given the wide variety of existing biochemical profiles and the slow growth characteristics which allow other organisms to overgrow the A. salmonicida. Herein, we report the development of a specific immunoassay using gold‐conjugated polyclonal antibodies for the rapid detection of A. salmonicida in fish tissues. Monodispersible 13‐nm gold nanoparticles were coated with polyclonal antibodies specific to A. salmonicida. Reddish purple agglutination of gold particles indicated the presence of A. salmonicida in samples. Positive reactions were detected visually with the naked eye. No agglutination was observed when A. salmonicida antibody‐coated gold nanoparticles were tested with other common bacterial fish pathogens, thereby verifying the specificity of the assay. The assay could detect A. salmonicida in fish tissues down to 1 × 10⁴ CFU mL^?1, and results were obtained within 45 min. The antibody‐coated gold nanoparticles were stable for at least 2 months at 4°C. The immunoassay using antibody‐coated gold nanoparticles represents a promising tool for the rapid and specific detection of A. salmonicida in fish tissues.  相似文献   

Outbreaks of an iridovirus in marbled sleepy goby, Oxyeleotris marmoratus (Bleeker), cultured in southern China     

Wang Q  Zeng WW  Li KB  Chang OQ  Liu C  Wu GH  Shi CB  Wu SQ 《Journal of fish diseases》2011,34(5):399-402

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