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51.
The effect of increasing levels of applied phosphorus (P) and boron (B) on the growth and the concentration and uptake of P and B were examined in eight maize genotypes (Furio, Riogrande, Sele, DK 743, Helix, Missouri, Betor, and Poker) with two individual greenhouse experiments. Phosphorus was applied at 0, 50, and 100 mg kg‐1 in Experiment I and B at 0, 10, and 30 mg kg‐1 levels in Experiment II. Application of B resulted in increased concentration and uptake of B and a decreased P concentration and uptake in all genotypes. The dry weight of all genotypes was decreased by application of B. However, applied P decreased B concentration and uptake and increased P concentration and uptake of the genotypes. The dry weight of all genotypes was increased by application of P. These experiments show that B is more toxic in the absence of rather than the presence of P, and that this toxicity could be alleviated with applications of P in the calcareous soils of semiarid areas. 相似文献
52.
A glasshouse study was conducted to investigate the effects of interspecific complementary and competitive root interactions and rhizosphere effects on phosphorus (P) and iron (Fe) nutrition of mixed grown chickpea (Cicer arietinum L.) and barley (Hordeum vulgare L.). In order to provide more physiological evidence on the mechanisms of interspecific facilitation, we determined phosphatase activities in plant and rhizosphere, and root ferric reducing capacity (FR), Fe-solubilizing activity (Fe-SA) and rhizosphere pH. The results of the experiment revealed that biomass yield of barley was significantly increased by associated chickpea as compared to monocultured barley, while mixed cropping caused a slight decreases in the biomass yield of chickpea. The rhizosphere was strongly acidified under chickpea and chickpea/barley mixed cropping and this acidification, in turn, increased the available P, Fe(II) and DTPA-Fe concentrations in the rhizosphere. Fe-solubilizing activity (Fe-SA) and ferric reducing (FR) capacity of the roots were higher in both species grown in mixed culture relative to their monoculture which may improve Fe nutrition of both species. Leaf acid phosphatase (APase, EC 3.1.3.2) activity was higher in both plants under mixed cropping that may improve P nutrition of barley by chickpea. 相似文献
53.
Pepper (Capsicum annuum L.) plants grown in pots were irrigated with the nutrient solutions containing 50, 75, and 100 mM NaCl or a control solution. Salinity markedly decreased plant growth. Increasing salinity levels increased stomatal resistance and sodium (Na), chloride (Cl), proline contents of the plants. Potassium (K), total‐nitrogen (N), and chlorophyll content of the plants were decreased under high salinity conditions. 相似文献
54.
A new Microsporidium sp. infects Rhizophagus grandis Gyllenhall, a beetle which preys on the bark beetle Dendroctonus micans Kugellan in Turkey. Mature spores are single, uninucleate, oval in shape (3.75 +/- 0.27 microm in length by 2.47 +/- 0.13 microm in width), with a subapically fixed polar filament. The polar filament is anisofilar, coiled in 7-8 normal and 3-4 reduced coils. Other characteristic features of the microsporidium are the four/five nuclear divisions to form 16/32 (commonly 16) spores, subpersistent sporophorous vesicles (pansporoblasts) remaining till formation of the endospore, and the vesicles dissolved with free mature spores. The polaroplast is divided into three zones: an amorphous zone, dense layers, and a lamellartubular area extending to the central part of the spore. 相似文献
55.
Application of a fully automatic analysis tool to assess the activity of broiler chickens with different gait scores 总被引:1,自引:0,他引:1
A. Aydin 《Computers and Electronics in Agriculture》2010,73(2):194-199
Monitoring the activity of broilers is a potential way for determining gait score level at commercial farms. In this study, a fully automatic monitoring technique was developed to measure the activity of broiler chickens with different gait score levels. We carried out two experiments in order to assess the relationship between gait scores obtained by human experts and activity levels quantified by an automatic image monitoring system. The chickens were scored for their degree of lameness by experts according to the method of Kestin et al. (1992). For each experiment, a total of 30 birds, on day 32 were selected from a local commercial farm. Five birds were selected in each of six gait score groups (GS0-GS5). The activity levels were obtained for all gait scores by using an automatic image monitoring system. For this purpose, video surveillance images of broilers with six different predefined gait scores were analysed. In both experiments, there was a significant relation between gait score by experts and activity monitored by image analysis. The broilers with gait score 3 (GS3) showed significantly higher activities than the other gait scores in both experiments (P < 0.05), possibly due to their need for more feed. In both experiment, GS4 and GS5 showed significantly lower activities (P < 0.05). Overall, the results show that automatic camera monitoring system can provide an automatic tool in determination the activity in relation to gait score. This activity information can be used further to identify the effects of gait score on broiler behaviour. 相似文献
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Mustafa Durmus Deniz Ayas Mehmet Aydin Ali Riza Kosker Yilmaz Ucar Yesim Ozogul 《Journal Of Aquatic Food Product Technology》2018,27(6):749-758
The present paper examines the impacts of gender and season variables on the nutritional composition and metal levels of warty crab caught in the central Black Sea region (Ordu). Crab samples were caught over four seasons, using gillnets, trammel net, and SCUBA diving. Results of chemical analysis showed that protein, lipid, moisture, and total mineral substance level ranges of male crabs were 20.45–22.64%, 0.95–1.27%, 75.44–77.09%, and 1.63–2.08%, while these ranges in female individuals were determined as 19.45–21.46%, 0.63–0.92%, 75.44–77.44%, and 2.08–3.28%, respectively. Macro and trace element levels in crab muscle tissue were determined as K > P > Na > Ca > Mg and Zn > Fe > Cu > Mn > Se > Ni > Mo > Co, respectively. Cd and Pb levels in crab muscle tissue were determined to be lower than the limit values given in codices independent of the seasonal variables. However, as the levels were found to be above the limit values, metal concentrations in crabs were also evaluated based on provisional tolerable daily intake and provisional tolerable weekly intake limits. 相似文献
58.
Previous studies have shown that salicylic acid (SA) plays a role in the response of plants to salt and osmotic stresses. Therefore, an experiment was conducted to investigate the impact of exogenous salicylic acid on the growth, physiology and antioxidant activity of carrot (Daucus carota L. cv. Nantes) grown under combined stress of salinity and boron toxicity. The treatments consisted of salt (control, NaCl, and Na2SO4), boron (−B: 0 and +B: 25 mg B kg−1) and salicylic acid (−SA: 0 and +SA: 0.5 mmol SA kg−1). The diameter of the storage root was increased by NaCl salinity in the absence of B toxicity, however, it was increased by Na2SO4 salinity under B toxicity. For the storage root yield, NaCl salinity was more toxic than Na2SO4 salinity. With its role in plant growth regulation, SA application positively affected the storage root dry weight, S concentration, carotenoids and anthocyanin content and increased the total antioxidant activity (AA) of the shoot and storage root. SA application regulated proline and toxic ion (B, Cl) accumulation in the storage root and shoot. This study reports the long term effects of SA under stress conditions and reveals that SA was not as effective as in alleviating abiotic stress as reported in the literature conducted with short-term studies. That means long-term effects of SA would be significantly different from its short-term effects. 相似文献
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