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M. Curci M. D. R. Pizzigallo C. Crecchio R. Mininni P. Ruggiero 《Biology and Fertility of Soils》1997,25(1):1-6
Modification of soil environment by different farming practices can significantly affect crop growth. Tillage causes soil
disturbance, altering the vertical distribution of soil organic matter and plant nutrient supplies in the soil surface, and
it may affect the enzyme activity and microbial biomass which are responsible for transformation and cycling of organic matter
and plant nutrients. In this study, the influence of three conventional tillage systems (shallow plowing, deep plowing and
scarification) at different depths on the distribution and activity of enzymes, microbial biomass and nucleic acids in a cropped
soil was investigated. Analysis of variance for depth and tillage showed the influence of the different tillage practices
on the activity of some enzymes and on the nucleic acids. Glucosidase, galactosidase, nitrate reductase and dehydrogenase
activity were significantly affected by the three tillage modalities. Activity in the upper layer (0–20 cm) was higher in
the plots tilled by shallow plowing and scarification than in those tilled by deep plowing. Positive relationships were observed
between the soil enzymes themselves, with the exception of urease and pyrophosphatase activity. Moreover, significant correlations
were found between DNA and β-galactosidase, and between RNA and β-glucosidase, β-galactosidase, alkaline phosphatase and phosphodiesterase.
α-Glucosidase, β-galactosidase, alkaline phosphatase and phosphodiesterase were highly correlated with biomass C determined
by the fumigation-extraction method.
Received: 27 June 1996 相似文献
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VC McIver AS Tsang NE Symonds NR Perkins E Uquillas CM Dart LB Jeffcott AJ Dart 《Australian veterinary journal》2020,98(6):250-255
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A. Sofo A. Ciarfaglia A. Scopa I. Camele M. Curci C. Crecchio C. Xiloyannis A. M. Palese 《Soil Use and Management》2014,30(1):160-167
Sustainable soil management of orchards can have positive effects on both soils and crop yields due to increases in microbial biomass, activity and complexity. The aim of this study was to investigate medium‐term effects (12 yr) of two different management practices termed ‘sustainable’ (ST) and ‘conventional’ (CT) on soil microbial composition and metabolic diversity of a rainfed mature olive orchard in Southern Italy. ST included no‐till, self‐seeding weeds (mainly graminaceous and leguminosae), and mulch derived from olive tree prunings, whilst CT was managed by frequent tillage and included severe pruning with residues removed from the orchard. Microbial analyses were carried out by culture‐dependent methods (microbial cultures and Biolog®). Molecular methods were used to confirm the identification by light microscopy of the isolates of fungi and Streptomyces. Significantly more culturable fungi and bacteria were found in ST than in CT. The number of fungal groups in ST was also significantly greater than in CT. Overall and substrate‐specific Biolog® metabolic diversity indices of microbial communities and soil enzyme activities were greater in ST. The results demonstrate that soil micro‐organisms respond positively to sustainable orchard management characterized by periodic applications of locally derived organic matter. This study confirms the need to encourage farmers with orchards in the Mediterranean basin to practise soil management based on organic matter inputs associated with zero tillage to improve soil functionality. 相似文献
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Carmine Crecchio Maddalena Curci Patrizia Ricciuti Pacifico Ruggiero 《Soil biology & biochemistry》2007,39(6):1391-1400
Organic matter incorporation into soil can increase nutrient availability to plants but it can affect soil microbial communities. These in turn influence soil fertility and plant growth. Soil biochemical and microbiological properties are indicators of soil quality, but there is still no consensus as to how these should be used. Recent developments in molecular biology have provided new tools to obtain a view of the whole microbial community. The long-term impact of crop residue management on the microbial biomass, and on the activity and community structure of soil bacteria was evaluated in a clay soil of Southern Italy, where a monoculture of durum wheat (Triticum durum Desf.) was grown in semiarid conditions, and burning or incorporation of post harvest plant residues were typical practices. The role of N-mineral fertilization, simultaneously with the ploughing in of crop residues and during the plant growth cycle was also investigated. Total bacterial counts of viable cells, biomass C, ATP content of soil microorganisms, genetic fingerprinting of the total eubacterial community and of ammonia oxidizers were evaluated. Burning and incorporation did not affect microbial biomass C, ATP content, and total bacterial counts of viable cells although statistically relevant changes were detected among rhizosphere and bulk soil samples regardless of the crop residue management used. Molecular fingerprinting confirmed that: no significant change in the composition and diversity of total bacteria, as well as of ammonia oxidizers was induced by the crop residue managements; that soil bacteria were more sensitive to N fertilizer application during the plant growth cycle; and that rhizosphere soil samples were significantly different from those of the bulk soil. As microbiological and genetic factors related to soil fertility were not affected significantly, the long-term incorporation of crop residues, under the field conditions investigated, is a sustainable practice to manage post-harvest residues. 相似文献
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Short-term effects of municipal solid waste compost amendments on soil carbon and nitrogen content, some enzyme activities and genetic diversity 总被引：2，自引：0，他引：2
Carmine Crecchio Maddalena Curci Rosaria Mininni Patrizia Ricciuti Pacifico Ruggiero 《Biology and Fertility of Soils》2001,34(5):311-318
Municipal solid waste (MSW) composts have been frequently used as N and C amendments to improve soil quality and to support plant growth, with the additional benefit of reducing waste disposal costs. However, attention has been paid to the risks of MSW use for the soil environment. The presence of heavy metals in MSW composts can affect some microbiological characteristics of soil such as the structure of the soil microbiota, which are responsible for the transformations making nutrients available to plants. The effects of MSW compost and mineral-N amendments in a 2-year field trial on some physical-chemical properties, some enzyme activities and the genetic diversity of cropped plots (sugar beet-wheat rotation) and uncropped plots were investigated. Variations of pH were not statistically related to MSW compost and mineral-N amendments, or to the presence of the crop. Amendment with MSW compost increased the organic C and total N contents, and dehydrogenase and nitrate reductase activities of soil. In cropped plots amended with MSW compost, dehydrogenase activity was positively correlated with #-glucosidase activity, and both enzyme activities with organic C content. No MSW compost dosage effect was detected. No effects were observed on denaturing gradient gel electrophoresis and amplified rDNA restriction analysis patterns, indicating that no significant change in the bacterial community occurred as a consequence of MSW amendment. 相似文献
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Pasquale L. Curci Hélène Bergès William Marande Marco Maccaferri Roberto Tuberosa Gabriella Sonnante 《Euphytica》2018,214(2):36
Wheat is one of the most widely grown cereal crops based on the amount of calories it provides in the human diet. Durum wheat (Triticum turgidum ssp. durum) is largely used for production of pasta and other products. In order to use genetic knowledge to improve the understanding of N-use efficiency, we carried out, for the first time in durum wheat, the isolation and the characterization of four members of the asparagine synthetase (AsnS) gene family. Phylogenetic inference clustered the Ttu-AsnS1 (1.1 and 1.2) and Ttu-AsnS2 (2.1 and 2.2) genes in AsnS gene class I, which is present in monocots and dicots. Class I genes underwent a subsequent duplication leading to the formation of two subgroups. Plants of Svevo cultivar were grown under N-stress conditions and expression of the four AsnS genes was investigated at three developmental stages (seedling, booting, and late milk development), crucial for N absorption, assimilation and remobilization. AsnS1 genes were down-regulated in N-stressed roots, stems and leaves during seedling growth and booting, but seemed to play a role in N remobilization in flag leaves during grain filling. AsnS2 genes were scarcely expressed in roots, stems, and leaves. In N-stressed spikes there was no differential expression in any of the genes. The genes were mapped in silico using a durum wheat SNP map, assigning Ttu-AsnS1 genes to chromosome 5 and Ttu-AsnS2 to chromosome 3. These findings provide a better understanding of the role of ASN genes in response to N stress in durum wheat. 相似文献
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David J. Connolly BSc BVetMed PhD Cert SAM Cert VC Dipl ECVIM-CA MRCVS Gina Neiger-Aeschbacher Dr.med.vet. Dipl ACVA Dipl ECVA MRCVS Daniel J. Brockman BVSc CVR CSAO Dipl ACVS/ECVS ILTM MRCVS 《Journal of Veterinary Cardiology》2007,9(2):123-128
Acquired tricuspid valve stenosis (TVS) is a rare complication of endocardial lead placement in humans that has not been described in the veterinary literature. We describe a 6.5-year-old Border terrier that was presented with right-sided congestive heart failure 5.5 years after placement of a transvenous pacemaker. Severe TVS was confirmed by cardiac ultrasonography and appeared to be secondary to excessive endocardial pacemaker lead within the right atrium. Repositioning of the lead proved impossible and subsequent postmortem examination demonstrated fusion of the tricuspid valve (TV) leaflets around the endocardial lead with associated narrowing of the tricuspid valve orifice. In addition, the loop of the endocardial lead was anchored by thick fibrous tissue to the right atrial wall. This case report suggests that if sufficient endocardial lead is left inside the heart, in dogs undergoing transvenous pacemaker therapy, the redundant lead can become adherent to the tricuspid valve apparatus and cause valvular stenosis. 相似文献