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41.
42.
To control downy mildew of sweet basil (Ocimum basilicum L.), incited by Peronospora belbahrii Thines, a number of compounds were tested in 2011 and 2012 under glasshouse conditions. These included copper-based fungicides, biocontrol agents, and compounds previously reported to induce resistance in plants to pathogens. Results were compared with those provided by fungicides registered for downy mildew control in Italy. The tested compounds were used alone or applied in rotation in spray programs. In all trials, the greatest reduction in disease incidence and severity was found with treatments that included metalaxyl-M?+?copper hydroxide, a mineral fertilizer ‘Alexin’, mandipropanid, and azoxystrobin. The glucohumates activator complex and acibenzolar-S-methyl also provided significant disease control (P?<?0.05). The mineral fertilizer Alexin, the glucohumates activator complex and acibenzolar-S significantly reduced disease incidence and severity 20 days after the last treatment compared with the untreated control (P?<?0.05). Among the copper-based products, the greatest reductions in disease incidence and severity were provided by copper hydroxide with terpenic alcohols and copper oxychloride?+?copper hydroxide. The mineral fertilizer Kendal and prohexadione-Ca, as well as mustard oil, partially reduced disease incidence and severity compared with the untreated control (P?<?0.05), whereas the biocontrol agent Bacillus subtilis QST 713 and thyme oil extract were not effective in two out of three trials. When different combinations of various products used in rotation were tested, effective control was found either using a rotation of fungicides with compounds that can induce resistance, as well as by using rotation with different resistance-inducing compounds on their own.  相似文献   
43.
The critical crop nitrogen uptake is defined as the minimum nitrogen uptake necessary to achieve maximum biomass accumulation (W). Across a range of crops, the critical N uptake is related to W by a power function with a coefficient less than unity that suggests crop N uptake is co-regulated by both soil N supply and biomass accumulation. However, crop N demand is also often linearly related to the expansion of the leaf area index (LAI) during the vegetative growth period. This suggests that crop N demand could be also linked with LAI extension. In this paper, we develop theory to combine these two concepts within a common framework. The aim of this paper is to determine whether generic relationships between N uptake, biomass accumulation, and LAI expansion could be identified that would be robust across both species and environment types. To that end, we used the framework to analyze data on a range of species, including C3 and C4 ones and mono- and di-cotyledonous crops. All crops were grown in either temperate or tropical and subtropical environments without limitations on N supply. The relationship between N uptake and biomass was more robust, across environment types, than the relationship of LAI with biomass. In general, C3 species had a higher N uptake per unit biomass than C4 species, whereas dicotyledonous species tended to have higher LAI per unit biomass than monocotyledonous ones. Species differences in N uptake per unit biomass were partly associated with differences in LAI and N-partitioning. Consequently the critical leaf-N uptake per unit LAI (specific leaf nitrogen, SLN) was relatively constant across species at 1.8–2.0 g m−2, a value that was close to published data on the critical SLN of new leaves at the top of the canopy. Our results indicate that critical N uptake curves as a function of biomass accumulation may provide a robust platform for simulating N uptake of a species. However, if crop simulation models are to capture the genotypic and environmental control of crop N dynamics in a physiologically functional manner, plant growth has to be considered as the sum of a metabolic (e.g. leaves) and a structural (e.g. stems) compartment, each with its own demand for metabolic and structural N.  相似文献   
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A 7-year-old male German Shepherd dog in poor body condition had a 3-month history of intermittent hematuria. Nonregenerative anemia, mild leukocytosis, marked hypoalbuminemia, and hematuria were observed. Subsequently, marked neutrophilia and moderate monocytosis were noted; anemia, hypoalbuminemia, and hematuria persisted; and the dog developed disseminated intravascular coagulation. Ultrasonographic examination of the abdomen revealed the presence of an enlarged and irregularly shaped right kidney with a large area of cavitation, and a nephrectomy was performed 30 days after initial examination. Cytologic examination of fine-needle aspirates and imprints of the right kidney revealed a neoplastic cell population suggestive of renal carcinoma. The histopathologic diagnosis was chromophobic cystic-papillary renal carcinoma. The tumor cells expressed granulocytic/macrophage-colony-stimulating factor (GM-CSF), detected by immunohistochemical staining, and elaboration of GM-CSF by the tumor may have mediated the leukocytosis in this dog. Following excision of the tumor, neutrophil and monocyte counts were only mildly increased. The dog died 135 days after initial presentation, and a necropsy was not permitted. Paraneoplastic neutrophilic leukocytosis is an uncommon finding and may be caused by elaboration of CSF by neoplastic cells.  相似文献   
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47.
The Valdostana is a local dual purpose cattle breed developed in Italy. Three populations are recognized within this breed, based on coat colour, production level, morphology and temperament: Valdostana Red Pied (VPR), Valdostana Black Pied (VPN) and Valdostana Chestnut (VCA). Here, we investigated putative genomic regions under selection among these three populations using the Bovine 50K SNP array by combining three different statistical methods based either on allele frequencies (FST) or extended haplotype homozygosity (iHS and Rsb). In total, 8, 5 and 8 chromosomes harbouring 13, 13 and 16 genomic regions potentially under selection were identified by at least two approaches in VPR, VPN and VCA, respectively. Most of these candidate regions were population-specific but we found one common genomic region spanning 2.38 Mb on BTA06 which either overlaps or is located close to runs of homozygosity islands detected in the three populations. This region included inter alia two well-known genes: KDR, a well-established coat colour gene, and CLOCK, which plays a central role in positive regulation of inflammatory response and in the regulation of the mammalian circadian rhythm. The other candidate regions identified harboured genes associated mainly with milk and meat traits as well as genes involved in immune response/inflammation or associated with behavioural traits. This last category of genes was mainly identified in VCA, which is selected for fighting ability. Overall, our results provide, for the first time, a glimpse into regions of the genome targeted by selection in Valdostana cattle. Finally, this study illustrates the relevance of using multiple complementary approaches to identify genomic regions putatively under selection in livestock.  相似文献   
48.
The use of organic amendments in agriculture could sustain crop production and preserve the agroecosystem, due to their importance in the conservation of organic matter in soil. The objective of this research was to evaluate the effects of differing organic fertilizers and of previous crops on lettuce growth, nutritional status and yields. The effects on soil characteristics were further investigated. The research was carried out during two years (2006 and 2007) at Metaponto (MT) in southern Italy, on lettuce crops cultivated after eggplant and melon to avoid their continuous cropping. The effects of application of a mineral fertilizer (MF), and of three treatments with organic fertilizers (commercial stable manure - OM; anaerobic digestate based on wine distillery wastewater - AD; composted municipal solid organic wastes coming from the separate collection - MSW) were studied. Head average weight, leaf area index, nitrate content and SPAD readings during the cropping cycles did not show significant differences among fertilizer treatments. On the contrary, marketable yield and head average weight at the harvest presented significantly different among the three organic fertilizers. The average marketable yield and head average weight of organic fertilizers experimental (AD and MSW treatments) decreased of 16 and 17%, respectively, compared to OM treatment. The previous melon crop influenced positively all analyzed parameters of the lettuce compared with previous eggplant crop. The previous melon crop reached the highest marketable yield with an increase of 59% compared with previous eggplant crop. Compared to the mineral fertilizer, the organic ones significantly increased the extracted fraction of soil organic carbon (6.9, 10.7 and 14.9% for OM, AD and MSW, respectively), without significant changes for the humic and fulvic content.  相似文献   
49.
The effect of 8-day-old exposure maize seedlings with cadmium (Cd) or zinc (Zn), separately, are described with special attention being given to ultrastructural changes as well as changes of the growth. These elements, frequent pollutants found in the soil, were added as 1 mM solutions to nutrient solution used for roots and shoots of maize seedlings, investigated 8 days after germination. The symptoms of heavy metal toxicity were clear showing that Cd inhibits root growth more strongly than the shoots and more effectively than zinc ions. The results of scanning electron microscopy revealed changes in the leaf surface, particularly in the guard cells of the stomata. The ultrastructural analyses of the parenchyma mesophyll cells showed extensive chloroplast disorganization, mainly affecting the thylakoid membranes and grana.  相似文献   
50.

Purpose

Charcoal is utilized in Brazil for the metallurgical industry. Small size pieces, called charcoal fines, are rejected and sometimes are used to produce energy by burning. This charcoal can be used as soil conditioner to improve retention of metal ions in soil. However, changing the charcoal's surface chemistry via oxidation may increase retention of metal ions.

Materials and methods

Two kinds of oxidants were employed, nitric acid and selenium dioxide/hydrogen peroxide. Vanadyl ion (VO2+) and copper ion (Cu2+) were utilized as probe to study the metal ion complexation by the partially oxidized charcoal obtained. FTIR and EPR spectroscopy were used to characterize the materials.

Results and discussion

Oxidation with nitric acid increased nitrogen content, while oxidation with SeO2/H2O2 elevated carbon content of treated charcoals. Organic free radicals (OFRs) with the unpaired electron in p orbitals of aromatic structures were confirmed by the EPR g-factors that ranged from 2.0038 to 2.0031. The oxidation with selenium dioxide/hydrogen peroxide formed charcoal with largest quantity of OFR. Loading charcoal with VO2+ and Cu2+ resulted in formation of complexes were oxygen acted as coordination atom. The formed complexes were of axial symmetry. The configurations around the Cu2+ ions were: CUNCu2+ complex (more stable square planar symmetry) and CFNCu2+ complex (less stable distorted tetrahedral configuration). Both complexes had oxygen as coordinating atoms. CFNVO2+ and CFSeVO2+ complexes presented complexation sites of axial symmetry, C4v, with oxygen as coordinating atoms.

Conclusions

The oxidative treatment of charcoal with SeO2/H2O2 is more appropriate to produce soil organic conditioner for complexation of metal ions.  相似文献   
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