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91.

The present study investigated the effects of monovalent and bivalent vaccines against Streptococcus iniae and Vibrio harveyi on growth performance, blood biochemical parameters, immune system, and antioxidant defense of Asian seabass (Lates calcarifer) fingerlings. Fish were exposed to seven experimental groups containing phosphate buffer saline (control), S. iniae vaccine by injection, S. iniae vaccine by immersion method, V. harveyi vaccine by injection, V. harveyi vaccine by immersion method, S. iniae/V. harveyi vaccines by immersion method, and S. iniae/V. harveyi vaccines by injection in triplicate for 60 days. Vaccination resulted in a significant alteration of the final weight (FW), feed conversion ratio (FCR), daily weight gain (DWG), relative growth rate (RGR), glucose, lysozyme, and complement levels at 60 days post-vaccination. Also, serum glutathione activity significantly increased in group SVIM (S. iniae/V. harveyi vaccines by immersion method) compared to the control group at 60 days post-vaccination. The level of MDA in serum was significantly decreased in SIN (S. iniae vaccine by injection) and SVIM groups compared to the control group 60 days post-vaccination where the value of this parameter was significantly higher in VIM (V. harveyi vaccine by immersion method) and SVIN (S. iniae/V. harveyi vaccines by injection) groups. The results of this study suggest that exposure to monovalent and bivalent vaccines against S. iniae and V. harveyi could alter the growth performance, nonspecific immune response, and antioxidant defense of Asian seabass fingerlings.

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92.
Fusarium head blight (FHB) is a devastating disease that reduces the yield, quality and economic value of wheat. For quantitative trait loci (QTL) analysis of resistance to FHB, F3 plants and F3:5 lines, derived from a ‘Wangshuibai’ (resistant)/‘Seri82’(susceptible) cross, were spray inoculated during 2001 and 2002, respectively. Artificial inoculation was carried out under field conditions. Of 420 markers, 258 amplified fragment length polymorphism and 39 simple sequence repeat (SSR) markers were mapped and yielded 44 linkage groups covering a total genetic distance of 2554 cM. QTL analysis was based on the constructed linkage map and area under the disease progress curve. The analyses revealed a QTL in the map interval Xgwm533‐Xs18/m12 on chromosome 3BS accounting for up to 17% of the phenotypic variation. In addition, a QTL was detected in the map interval Xgwm539‐Xs15/m24 on chromosome 2DL explaining up to 11% of the phenotypic variation. The QTL alleles originated from ‘Wangshuibai’ and were tagged with SSR markers. Using these SSR markers would facilitate marker‐assisted selection to improve FHB resistance in wheat.  相似文献   
93.
Abstract

In this study, the effect of different levels of nitrogen (N) and potassium (K) fertilizers on vegetative fresh bulb yield, quality and biochemical attributes of sweet fennel were investigated in spring 2017 and 2018. Treatments consisted of 0, 50, 100, or 150?kg ha?1 of N and K in a randomized complete block design with three replications. Results showed that, the bulb fresh yield increased with application of N and K in both years, while the higher level of K had significant adverse effect in first year. Results also showed that sweet fennel bulb treated by N and K exhibited higher vitamin C, total phenols and flavonoid contents, and antioxidant capacity, especially in first year. In both years, alone or combined application of N and K increased total soluble solids (TSS) content as compared to control, and this effect was more pronounced in 2017 season. Macronutrient contents of bulb including magnesium (Mg), phosphorus (P), K, N, and calcium (Ca) were significantly enhanced by NK fertilizer, however an alone application of K decreased Ca and Mg nutrient contents. Therefore, to improve fresh bulb yield, quality and antioxidant capacity in sweet fennel, 150?kg ha?1 K and 100?kg ha?1 N is recommended.  相似文献   
94.
Hyperactivated Motility in Sperm   总被引:5,自引:0,他引:5  
Hyperactivation is a movement pattern seen in sperm at the site and time of fertilization in mammals. It may be critical to the success of fertilization, because it enhances the ability of sperm to detach from the wall of the oviduct, to move around in the labyrinthine lumen of the oviduct, to penetrate mucous substances and, finally, to penetrate the zona pellucida of the oocyte. The movement of hyperactivated sperm appears different under different physical conditions and in different species, but basically it involves an increase in flagellar bend amplitude and, usually, beat asymmetry. Presumably, a signal or signals exist in the oviduct to initiate hyperactivation at the appropriate time; however, none has yet been identified with certainty. While the signal transduction cascade regulating hyperactivation remains to be completely described, it is clear that calcium ions interact with the axoneme of the flagellum to switch on hyperactivation. Although hyperactivation often occurs during the process of capacitation, the two events are regulated by somewhat different pathways.  相似文献   
95.
Yari  Payman  Pasari  Babak  Rokhzadi  Asad  Mohammadi  Khosro 《Gesunde Pflanzen》2022,74(1):193-203

This experiment was conducted to study the effects of foliar application of silicon, sulfur, and flowering fruit set biostimulant on canola in the farmer’s condition in Darzian, 12?km from Marivan city in the northwest of Iran. The experimental layout was designed as a split-split plot in a randomized complete-block design, with three replications during two consecutive growing seasons, 2017–18 and 2018–19. The main factor included silicon application at two levels: control (0: non-application) and silicon application at 2?kg ha?1. Sub-factor was sulfur spraying at three levels (0, 1, and 2?L ha?1) and sub-sub-factor was Tecamin flower (Agri Tecno Fertilizantes, Valencia, Spain) spraying as a flowering fruit set biostimulant at three levels (0, 1, and 2?L ha?1). The results of the combined analysis showed that the number of grains per pod and biomass were increased significantly at the 1% level by silicon application. Sulfur application improved 1000-grain weight, grain yield, and biomass. This increase was 7.42% for grain yield. Tecamin also significantly increased all traits, including fertile and infertile pod numbers, grain number per pod, 1000-grain weight, grain yield, and biomass. As the most important economic traits, Tecamin increased grain yield by 14.12% compared to controls. Among the treatments, the effect of Tecamin on increasing grain yield was superior. In this experiment, some traits were significantly affected by interaction effects of treatments.

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96.
WZ Li  SS Xie  LX Qian  BH Chang  BS Zou  WY Zhou  RA Zhao  G Wang 《Science (New York, N.Y.)》1996,274(5293):1701-1703
Large-scale synthesis of aligned carbon nanotubes was achieved by using a method based on chemical vapor deposition catalyzed by iron nanoparticles embedded in mesoporous silica. Scanning electron microscope images show that the nanotubes are approximately perpendicular to the surface of the silica and form an aligned array of isolated tubes with spacings between the tubes of about 100 nanometers. The tubes are up to about 50 micrometers long and well graphitized. The growth direction of the nanotubes may be controlled by the pores from which the nanotubes grow.  相似文献   
97.
Grain yield and yield components are the main important traits involved in durum wheat (Triticum turgidum L.) improvement programs. The purpose of this research was to identify quantitative trait loci (QTL) associated with yield components such as 1000 grain weight (TGW), grain weight per spike (GWS), number of grains per spike (GNS), spike number per m2 (SN), spike weight (SW), spike harvest index (SHI) and harvest index (HI) using microsatellite markers. Populations of F3 and F4 lines derived from 151 F2 individuals developed from a cross between Oste-Gata, a drought tolerant, and Massara-1, a drought susceptible durum wheat genotypes, were used. The populations were evaluated under four environmental conditions including two irrigation regimes of drought stress at terminal growth stages and normal field conditions in two growing seasons. Two hundred microsatellite markers reported for A and B genomes of bread wheat were used for parental polymorphism analysis and 30 polymorphic markers were applied to genotype 151 F2:3 families. QTL analysis was performed using genome-wide single marker regression analysis (SMA) and composite interval mapping (CIM). The results of SMA revealed that about 20% of the phenotypic variation of harvest index and TGW could be explained by Xcfd22-7B and Xcfa2114-6A markers in different environmental conditions. Similarly, Xgwm181-3B, Xwmc405-7B and Xgwm148-3B and marker Xwmc166-7B were found to be associated with SHI and GWS, respectively. A total of 20 minor and major QTL were detected; five for TGW, two for GWS, two for GNS, three for SN, five for HI, two for SHI and one for SW. The mapped QTL associated with ten markers. Moreover, some of these QTL were prominent and stable under drought stress and non drought stress environments and explained up to 49.5% of the phenotypic variation.  相似文献   
98.
Durum wheat is grown in the Mediterranean region under stressful and variable environmental conditions. In a 4-year-long experiment, 14 genotypes [including 11 durum breeding lines, two durum (Zardak) and bread (Sardari) wheat landraces, and one durum (Saji) newly released variety] were evaluated under rainfed and irrigated conditions in Iran. Several selection indices [i.e. stress tolerance index (STI), drought tolerance efficiency (DTE), and irrigation efficiency (IE)] were used to characterize genotypic differences in response to drought. The GGE biplot methodology was applied to analyze a three-way genotype-environment-trait data. Combined ANOVA showed that the year effect was a predominant source of variation. The genotypes differed significantly (P < 0.01) in grain yield in the both rainfed and irrigated conditions. Graphic analysis of the relationship among the selection indices indicated that they are not correlated in ranking of genotypes. The two wheat landraces and the durum-improved variety with high DTE had minimum yield reduction under drought-stressed environments. According to STI, which combines yield potential and drought tolerance, the “Saji” cultivar followed by some breeding lines (G11, G8, and G4) performed better than the two landraces and were found to be stable and high-yielding genotypes in drought-prone rainfed environments. The breeding lines G8, G6, G4, and G9 were the efficient genotypes responding to irrigation utilization. In conclusion, the identification of the durum genotypes (G12, G11, and G4) with high yield and stability performance under unpredictable environments and high tolerance to drought stress conditions can help breeding programs and eventually contribute to increasing and sustainability of durum production in the unpredictable conditions of Iran.  相似文献   
99.
Trend analysis of reference evapotranspiration in the western half of Iran   总被引:6,自引:0,他引:6  
Reference evapotranspiration (ETo) is an important element of the hydrological cycle, and changes in ETo are of great significance for agricultural water use planning, irrigation system design and management. In this study, annual, seasonal and monthly trends in the Penman-Monteith ETo at 20 meteorological stations during 1966-2005 in the western half of Iran were examined using the Mann-Kendall test, the Sen's slope estimator and the linear regression. Annual analysis of the ETo series indicated a positive trend in 70% of the stations according to the Mann-Kendall test and the Sen's slope estimator and in 75% of the stations according to the linear regression. The magnitude of significant positive trends in annual ETo varied from (+)11.28 to (+)2.30 mm/year. On the seasonal scale, stronger increasing trends were identified in ETo data in winter and summer compared with those in autumn and spring. Meanwhile, the highest numbers of stations with significant trends were found in the monthly ETo series in February, while the lowest numbers of stations with significant trends were observed in November. Analysis of the impact of climatic variables on the significant increasing trend in ETo showed that the increasing trend was mainly caused by a significant increase in air temperature during the study period.  相似文献   
100.
Information regarding the evaluation of tillage effects on soil properties and rainfed wheat (Triticum aestivum L.) cultivars of Iranian fields is not available. Therefore, this research was conducted in Sanandaj (west of Iran) using a randomized complete block design in a split-plot arrangement. Three types of tillage including conventional tillage (moldboard plow to soil depth of 30 cm plus disk harrow twice), minimum tillage (chisel plow to soil depth of 15 cm plus disk harrow once) and no-tillage are assigned to the main plots. Wheat cultivars (Sardari and Azar2) were randomly distributed within the subplots in each tillage system. Results showed that the greatest bulk density and cone index were found in the minimum tillage and no tillage systems. The highest rate of grain yield was obtained in the minimum tillage system. The grain yield of Sardari cultivar (1624.1 kg ha?1) was significantly greater than that of Azar2 (1572 kg ha?1). Minimum tillage improved soil physical properties and wheat growth compared with the other tillage systems. No tillage increased microbial biomass carbon and bacteria number in soil compared with the other tillage systems. We conclude that using minimum tillage for Sardari cultivar will be more effective compared with other treatments.  相似文献   
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