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141.
Guillermo Portillo‐Clark Ramón Casillas‐Hernández Rosalía Servín‐Villegas Francisco J. Magallón‐Barajas 《Aquaculture Research》2012,44(1):22-30
This study was performed to determine the growth and survival patterns of the juvenile yellowleg shrimp Farfantepenaeus californiensis cohabiting with the green feather alga Caulerpa sertularioides over a range of temperatures (18, 22, 25, 28 and 32°C) found throughout the year in the Gulf of California. From an initial weight of 46 ± 10 mg, shrimp cohabiting with green feather algae increased in weight by an average of 0.57 (±0.07), 5.44 (±0.45), 6.36 (±0.37), 7.66 (±0.26) and 5.96 (±0.59) g at 18, 22, 25, 28 and 32°C, respectively, whereas shrimp grown without seaweed increased in weight by an average of 0.28 (±0.026), 2.66 (±0.24), 3.15 (±0.49), 4.00 (±0.67), and 3.54 (±0.09) g respectively. Statistically significant differences were observed for the growth rates of juvenile yellowleg shrimp in the presence of C. sertularioides and peak growth was observed at 28°C in experiments with macroalgae. No significant differences were observed for shrimp survival except at 32°C without macroalgae, where survival was lower. These results suggest a beneficial and growth‐promoting effect of cohabitation with live C. sertularioides on F. californiensis. 相似文献
142.
S. KitchluG. Ram Sushma KoulKiran Koul K.K. GuptaAshok Ahuja 《Industrial Crops and Products》2011,33(3):584-587
Podophyllum hexandrum Royle (Syn. P. emodi Wale) a perennial rhizomatous herb found in alpine region distributed in the entire range of Himalayas from Ladakh to Sikkim at an altitude of 3000-4200 m asl is an preferred commercial source of Podophyllum lignans. It contains three times more Podophyllotoxin than the American species, Podophyllum peltatum. The present study was aimed to investigate variation of Podophyllum lignans contents based on six marker compounds viz. Podophyllotoxin; Deoxypodophyllotoxin; Picropodophyllotoxin; Podophyllotoxin β-d-glucopyanoside; Isopicropodophyllone; 4′-Demethyldeoxypodophyllotoxin, β-d-lucopyanoside, in P. hexandrum population growing at three locations. Further, ontogenetic and morphogenetic variations of Podophyllum lignan contents were studied to investigate dynamics of accumulation of these compounds. Representative collections from three locations viz., Panikhar, Padam and Tangoli located in Trans Himalayan semi-desert region of Zanskar valley were harvested at three stages (dormancy, active growth and maturity). Plants were dissected into root, rhizome and rhizome-buds, dried separately and assayed for Podophyllum lignan contents by high performance liquid chromatography. 相似文献
143.
Effect of Ocimum sanctum Linn. (Tulsi) extract on the immunity and survival of Labeo rohita (Hamilton) infected with Aeromonas hydrophila
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A 60 days study was conducted to evaluate the efficacy of water extract of Ocimum sanctum Linn. leaf on the immune response and disease resistance of Labeo rohita fingerlings against the Aeromonas hydrophila infection. Ocimum sanctum extract was incorporated in the diets (at 0.0%, 0.05%, 0.1%, 0.2%, 0.5% and 1%) of Labeo rohita, rohu fingerlings (6.6 ± 0.013 g). After 42 days blood, plasma and serum were sampled to determine super oxide anion production, lysozyme activity, total immunoglobulin in plasma, blood glucose, serum total protein, albumin, globulin, albumin:globulin ratio, WBC, RBC, haemoglobin content. Fish were challenged with A. hydrophila after 42 days and mortalities were recorded over 18 days post infection. The results demonstrate enhanced super oxide anion production, lysozyme activity, total immunoglobulin in plasma, serum total protein, globulin, total RBC counts, total WBC counts and haemoglobin content (P < 0.05) in treatments group compared with control group. Dietary O. sanctum extracts of 0.2% showed significantly (P < 0.05) higher protection relative percentage survival (RPS 40.00 ± 5.773%) against A. hydrophila infection than control. These results indicate that O. sanctum leaf extract stimulates the immunity and makes L. rohita more resistant to bacterial infection (A. hydrophila). 相似文献
144.
A. González-Ortiz J. J. Ramírez-García M. J. Solache-Ríos 《Water, air, and soil pollution》2018,229(10):340
Clindamycin (CLD), an antibiotic derivate of lincomycin, is widely used; the presence of this drug in the wastewater and the environment could produce resistance in bacteria. In this work, the sorption of this drug by two surfactant-modified zeolitic tuffs was studied considering contact time, initial concentration, pH, and temperature. The kinetic behavior indicates that the equilibrium times were between 15 and 12 h for all materials, and the results were best adjusted to Ho and Mc Kay model. The highest adsorption was obtained with the hexadecyltrimethylammonium-modified zeolitic tuff from Oaxaca, Mexico (1.56 mg/g). The sorption isotherms obtained showed a linear behavior, indicating a partition mechanism. The thermodynamic parameters were determined from the isotherms at different temperatures and Van Ho equation; the processes are exothermic and not spontaneous. The best pH for the adsorption is between 8 and 11. The results show that the modified zeolitic tuffs are potential materials for the adsorption of CLD from water. 相似文献
145.
The phytase is a key enzyme to hydrolyze phytic acid present in wheat grains and improves the bio-availability of micronutrients in monogastric animals. Phytase trait being contributed by specific regions of the genome requires identification of these regions, using suitable molecular markers. Hence, in the present investigation we attempted to develop a PCR-based marker that detects the phytase level in wheat. Six sets of PCR primers were designed on the basis of nucleotides sequence variation found in the sequence of both varieties. Out of six set of primers, one set amplified two different sized bands, i.e. 334 bp and 295 in two wheat cultivars C-306 (low phytase) and DBW 17 (high phytase), respectively. It exhibited a polymorphic banding pattern with length polymorphism and clearly separating low and high phytase genotypes. The primer set was also used for PCR of 46 synthetic hexaploids and 46 release varieties of wheat to validate the developed markers. Association among identified markers and phytase activity was found to be at 99.9% confidence level based on Fisher’s exact test (F-test). Therefore, this PCR primer set will be useful to select the wheat germplasm having high phytase levels and also in wheat breeding programs aimed at improving phytase levels in bread wheat cultivars. 相似文献
146.
Ana?Belén?González-FernándezEmail author José?Ramón?Rodríguez-Pérez Enoc?Sanz?Ablanedo Celestino?Ordo?ez 《Precision Agriculture》2017,18(4):525-573
This study describes a method for vineyard zone delineation based on spatial interpolation of data on annual monitoring of grape and vine growth from 2007 to 2012 for four commercial vines (Cabernet Sauvignon, Mencía, Merlot and Tempranillo) located in the Bierzo Denomination of Origen (NW Spain). A sampled grid of 20 × 29 m (14 vines/ha) was defined for each vineyard and data were collected for ten soil, six grape composition, three grape production and five vine vigour variables. Continuous maps of each variable were created by spatial interpolation from the sampled points. Several zone delineations were obtained by clustering—using the iterative self-organizing data analysis (ISODATA) algorithm—according to different combinations of the studied variables. The resulting zone delineations were analysed (ANOVA) in order to determine whether the variables in the two cluster classifications for two or three zones were statistically different from each other. The selected delineation was the cluster that included total soluble solids, titratable acidity, total phenolic content, pH, mean cluster weight and length of the internode in two zones. The results point to the feasibility of this approach to vineyard zone delineation. Further research is necessary to confirm the effectiveness of this approach for other locations and evaluate the usefulness of introducing new grape and vine variables. 相似文献
147.
Production of avocado trees infected with Phytophthora cinnamomi under different management regimes
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Avocado root rot is the most important disease of this fruit crop worldwide. This pathology may be caused by several biotic and abiotic agents, with the oomycete Phytophthora cinnamomi being the pathogen more frequently associated with poor phytosanitary conditions. There are disease control methods available that can reduce disease severity and allow plants to recover; however, they are not consistently and promptly applied. In addition, only chemical products are used by farmers as the preferred management method. This research aimed to evaluate different root rot management strategies in a commercial orchard. Data suggest that individual control methods are not as effective as when they are applied in combination, as in the T8 treatment (metalaxyl + mancozeb applied in drench; injection of potassium phosphite to each plant stem; potassium silicate applied in drench; addition of a layer of organic mulch and incorporation of 10 kg of composted substrate, both applied to the ground around the base of each tree). Using this strategy, the area under the disease progress curve for the avocado root rot was reduced by up to 68.6%, and the extra‐quality avocado fruit class increased by as much as 44% compared to the diseased control plants (T0) (P < 0.01). With the combined treatment T8, farm income showed a 9.5‐fold increase, probably due to an increase in the percentage of viable roots by up to 9.4‐fold, which would have improved nutrient and water uptake. 相似文献
148.
149.
Undernutrition in the parental and first generation provokes an organ‐specific response to oxidative stress on neonates of second filial generation of Wistar rats
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R. Baños‐Gómez N. S. Cruz‐Cansino T. Suarez‐Diéguez C. Valadez‐Vega E. Ramírez‐Moreno E. Alanís‐García J. A. Ariza‐Ortega J. J. Manríquez‐Torres E. Zamora‐Romo L. Delgado‐Olivares 《Journal of animal physiology and animal nutrition》2017,101(2):267-274
Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second‐generation neonates (F2) of undernourished rats. For this purpose, both parents in parental (F0) and first generation (F1) were fed with a low‐nutrient diet. Body mass and length decreased (p < 0.05) in F0, F1 and F2 being the F1 males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F2 neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ‐specific response, on F2 neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions. 相似文献
150.
D. V. Ramana Reddy T. Ram Prakash A. Srinivas P. Naga Sravani V. Visha Kumari 《Communications in Soil Science and Plant Analysis》2017,48(7):778-791
Experiments were conducted to test the superiority of treatment combinations of nitrogen (N; 0, 50, 100, 150, 200 kg ha?1), phosphorus (0, 30, 60, 90 kg ha?1) and potassium (0, 30, 60 kg ha?1) for finger millet during 2005–2007. Application of 200-90-60 kg ha?1 gave maximum yield of 1666, 1426 and 1640 kg ha?1 in 3 years, respectively. The yield regression model through soil and fertilizer nutrients gave predictability of 0.98, 0.97 and 0.98, with sustainability yield index (SYI) of 50.4, 49.4 and 52.5 in 2005, 2006 and 2007, respectively. Optimum nitrogen, phosphorus and potassium (NPK) doses for attaining yields of 800 and 1200 kg ha?1 were derived at soil nitrogen, phosphorus and potassium of 75–400, 10–70 and 150–750 kg ha?1. Fertilizer nitrogen, phosphorus and potassium ranged from 30–128, 3–19, 13–25 kg ha?1 and 105–203, 4–32, 27–39 kg ha?1 for attaining 800 and 1200 kg ha?1 yield, respectively. The doses could be adopted for attaining sustainable yields under semiarid Alfisols. 相似文献