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21.
Jantzi Sarah C. Dutton Christopher L. Saha Amartya Masikini Rosemary Almirall Jose R. 《Journal of Soils and Sediments》2019,19(1):478-490
Journal of Soils and Sediments - The goal of this study was to develop a “green chemistry” alternative sample preparation method for elemental analysis of sediments using laser ablation... 相似文献
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Akanksha Awasthi K. Raja Reddy Sukumar Saha Johnie N. Jenkins David M. Stelly 《Euphytica》2018,214(11):218
Limited knowledge about genetic and physiological traits associated with drought and low temperature stresses and narrow genetic diversity in Upland cotton (Gossypium hirsutum L.) are serious impediments in its genetic improvement. The objectives of this research were to determine the genetic and physiological traits associated with drought and low temperature effects and to identify chromosomal effects on these traits using chromosome substitution (CS) lines from three alien species of Gossypium, G. barbadense, G. tomentosum, and G. mustelinum, respectively. Two experiments were conducted to study low temperature and drought stress effects during seedling emergence and early growth stages in 21 cotton CS-lines with parent, Texas Marker (TM)-1. In Experiment I, plants were grown at optimum (30/22 °C) and low (22/14 °C) temperature conditions under optimum water and nutrient conditions. In Experiment II, plants were grown at optimum water (soil moisture content of 0.167 m3 m?3) and in drought (soil moisture content 0.105 m3 m?3) conditions under optimum temperature conditions. Above- and below-ground growth traits including several root traits of the CS lines were assessed at 25 days after sowing. The findings suggest which substituted chromosome or chromosome segment from the alien species likely harbors one or more genes for higher and lower tolerance to low temperature, respectively. CS-T04 and CSB08sh showed higher and lower tolerance to low temperature, respectively and CS-T04 and CS-B22sh showed higher and lower tolerance, respectively, to drought. CS lines are valuable analytical tool and useful genetic resources for targeted exploitation of beneficial genes for drought and low temperature stresses in Upland cotton. 相似文献
25.
Somidh Saha 《林业研究》2018,(4)
Wild cherry trees produce high-quality timber and provide multiple ecosystem services.However, planting and tending cherry stands in conventional rows are too costly.Therefore, low density group planting was trialled as an alternative to row planting.The mortality, growth, and quality of planted cherry trees were compared between the group and row planting.The influence of neighbourhood competition and light availability on growth and quality was studied.The group and row planting of cherry trees were established at a wind-thrown site in southwestern Germany in the year 2000.In group planting, five cherry seedlings and seven lime seedlings(Tilia cordata Mill.) were planted with a 1×1 m spacing.In total, 60 groups were planted per hectare with a 13×13 m spacing.In contrast, 3300 seedlings(2475 cherries and 825 limes) were planted per hectare in row planting with a 3×1 m spacing.Ten groups and plots(10×10 m) were randomly established in group and row planting stand, respectively.The survival rate, stability(height to diameter ratio), diameter, and height growth were significantly higher in group planting.In the group plantings,40.5% of cherry trees had straight stems and 13.5% had a monopodial crown compared with 15% with straight stems and 2% with a monopodial crown in row planting.The proportion of dominant cherry trees in canopy was 49% in groups compared with 22% in rows.The length of branch free bole was significantly higher in cherries planted in groups than those grown in rows.Intra-and interspecific competition reduced the growth and stability of cherry trees in row planting, but not in group planting.Light availability did not cause any significant effects on growth and quality between group and row planting.This first study on cherry group planting indicates that the survival rate, growth, and tree quality were higher in groups than in rows at this early development stage.The competition by naturally born seedlings was an important reason for the difference in performance between group and row planting.This study will encourage forest practitioners to establish more cherry group planting trials on multiple sites to test the effectiveness of this alternative technique as a tool of regeneration and restoration silviculture. 相似文献
26.
Effect of miconazole nitrate on immunological response and its preventive efficacy in Labeo rohita fingerlings against oomycetes Saprolegnia parasitica
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Mukta Singh Ratan Kumar Saha Himadri Saha Janmejay Parhi 《Journal of fish diseases》2018,41(10):1539-1548
This study evaluated the effect of sublethal doses of antifungal drug miconazole nitrate (MCZ) on immunological responses and its role as a prophylactic drug against S. parasitica in Labeo rohita fingerlings. Fish were fed with sublethal doses of MCZ, that is, T1—6.30 mgMCZ kgBW?1, T2—12.61 mgMCZ kgBW?1 and T3—25.22 mgMCZ kgBW?1, and sampling was done at different time intervals for 240 hr. Immunological parameters viz. lysozyme activity, oxygen radical production and plasma antiprotease activity showed significant enhancement (p < 0.05) in fish fed with T2 and T3 doses. Expression of immune‐relevant genes such as TLR‐22 and β2‐M showed significantly higher expression at 6 hr and 24 hr of sampling in both liver and head kidney. However, these genes showed a downregulation after 120 hr of sampling in both the tissues. Preventive efficacy study showed that single dose of MCZ provides protection against oomycetes up to the fourth day of infection. Significantly higher mortality was observed in control diet‐fed fish as compared to fish fed with MCZ medicated diet. Thus, it can be concluded that the MCZ can act as a potent antifungal agent for preventing oomycetes infection as well as to enhance the immune response. 相似文献
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Per McCord Vanessa Gordon Gopesh Saha Jacqueline Hellinga George Vandemark Richard Larsen Mark Smith David Miller 《Euphytica》2014,200(2):269-279
Alfalfa (Medicago sativa L.) is an internationally significant forage crop. Forage yield, lodging resistance and spring vigor are important agronomic traits conditioned by quantitative genetic and environmental effects. The objective of this study was to identify quantitative trait loci (QTL) and molecular markers associated with increased forage yield, resistance to lodging, and spring vigor. A backcross population composed of 128 progeny was developed by crossing the breeding parents DW000577 (lodging susceptible) and NL002724 (lodging-resistant) and back-crossing an individual F1 plant to the maternal parent (i.e. DW000577). A linkage map of NL002724 was developed based upon the segregation of 236 AFLP, SRAP, and SSR markers among the backcross progeny. The markers were distributed among 14 linkage groups, covering an estimated recombination distance of 1497.6 centiMorgans (cM). Replicated clones of both parents and backcross progeny were evaluated in the field for estimated forage yield, lodging, and spring vigor in Washington and Wisconsin during 2007 and 2008. Significant QTL were found for all three traits. In particular, two QTL for lodging resistance were identified that explained ≥14 % of trait variation, and were significant in all years and locations. Major QTL explaining over 25 % of trait variation for forage yield were detected in multiple environments at two separate locations on chromosome III. Several QTL for spring vigor were located in the same or similar positions as QTL for forage yield, possibly explaining the significant correlation between these traits. Molecular markers associated with the aforementioned QTL were also identified. 相似文献
29.
Seroprevalence of brucellosis in yaks (Poephagus grunniens) in India and evaluation of protective immunity to S19 vaccine 总被引:1,自引:1,他引:0
Bandyopadhyay S Sasmal D Dutta TK Ghosh MK Sarkar M Sasmal NK Bhattacharya M 《Tropical animal health and production》2009,41(4):587-592
The present study was carried out to explore the seroprevalence of brucellosis in yaks of North-Eastern hilly yak tracts of
Arunachal Pradesh, India. Of 374 animals tested, 23.79, 21.11 and 18.98% were found positive for brucellosis using avidin-biotin
ELISA (AB-ELISA), Rose-Bengal plate test (RBPT) and standard tube-agglutination test (STAT), respectively. The relative sensitivity
and specificity for STAT were 79.77 and 100%, respectively and the same for RBPT were 88.76 and 100%, respectively in comparison
to AB-ELISA. The alarming prevalence as recorded was highest among the yak cows (31.42%) followed by heifers (23.85%) and
bulls (8.88%). The immune response in yaks following standard dose of calfhood vaccination with Brucella abortus strain 19 vaccine showed that protective antibody level persisted up to 210 days. This is the first report from India on
prevalence of brucellosis and immunization with B abortus strain 19 vaccine in yaks. The present investigation would be a valuable guideline for future control measure and eradication
programme of brucellosis in yaks. 相似文献
30.
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