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161.
GR Loria R Puleio MR Schiavo P Giambruno E Bozzetta M Todaro 《Tropical animal health and production》2012,44(7):1323-1328
European and Italian legislation have banned use of growth promoters in livestock since 1988, but epidemiological data show that anabolic drugs are still being used illegally. Recent surveys carried out on the cattle farms in Northern Italy have confirmed the presence of growth-promoting hormones. Authors report data on growth performances in 80 Valle del Belice?×?Comisana weaned lambs experimentally treated with 17 beta-estradiol with 0.5?ml solution of oil Depot Estradiol ? (containing 5?mg of 17β-estradiol valerate) by intramuscular injection into the thigh. The experiment was founded by the National Ministry of Health, to validate histological test for surveillance and control of growth-promoting hormones in sheep. This study confirmed the strong correlation between clinical and anatomopathological features and growth performances of treated animals. Otherwise, no significant differences were found on in vivo performance of the lambs. Estradiol treatment showed heavier shoulders and necks on treated lambs, while the loins were significantly lighter. Moreover, lamb-estradiol-treated groups showed lower separable and inseparable fat percentage than lamb-control groups. 相似文献
162.
163.
This study aimed to reduce the gap of knowledge on white lupin drought tolerance variation, by assessing the grain yield of 21 landraces from major historical cropping regions, one variety and two breeding lines in a large phenotyping platform that imposed controlled severely stressed or moisture‐favourable conditions after an initial stage of favourable growth. Drought stress reduced grain yield by 79%. Genetic correlation coefficients indicated moderate consistency of genotype responses across conditions for grain yield (rg = 0.76), fairly high consistency for straw yield (rg = 0.85) and harvest index (rg = 0.91), and high consistency for flowering time (rg = 0.99). However, low genetic correlation for yield (rg = 0.31) occurred among a subset of genotypes with early phenology. Specific adaptation to either condition implied significant (p = 0.05) genotype × condition interaction of crossover type between well‐performing genotypes. Early flowering was an important stress escape mechanism, but intrinsic drought tolerance could be inferred from responses of a few genotypes. Various landraces out‐yielded the improved germplasm under stressed or favourable conditions. 相似文献
164.
Simone DI PRIMA Jess RODRIGO-COMINO Agata NOVARA Massimo IOVINO Mario PIRASTRU Saskia KEESSTRA Artemi CERD 《土壤圈》2018,28(3):463-477
Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality (SPQ). In this study, the SPQ of citrus orchards was assessed under three different soil managements, namely no-tillage using herbicides, tillage under chemical farming, and no-tillage under organic farming. Commonly used indicators, such as soil bulk density, organic carbon content, and structural stability index, were considered in conjunction with capacitive indicators estimated by the Beerkan estimation of soil transfer parameter (BEST) method. The measurements taken at the L'Alcoleja Experimental Station in Spain yielded optimal values for soil bulk density and organic carbon content in 100% and 70% of cases for organic farming. The values of structural stability index indicated that the soil was stable in 90% of cases. Differences between the soil management practices were particularly clear in terms of plant-available water capacity and saturated hydraulic conductivity. Under organic farming, the soil had the greatest ability to store and provide water to plant roots, and to quickly drain excess water and facilitate root proliferation. Management practices adopted under organic farming (such as vegetation cover between the trees, chipping after pruning, and spreading the chips on the soil surface) improved the SPQ. Conversely, the conventional management strategies unequivocally led to soil degradation owing to the loss of organic matter, soil compaction, and reduced structural stability. The results in this study show that organic farming has a clear positive impact on the SPQ, suggesting that tillage and herbicide treatments should be avoided. 相似文献
165.
Abundance,genetic diversity and sensitivity to demethylation inhibitor fungicides of Aspergillus fumigatus isolates from organic substrates with special emphasis on compost
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Slavica Matić Ulrich Gisi Davide Spadaro Massimo Pugliese Maria L Gullino 《Pest management science》2017,73(12):2481-2494
166.
滴灌施肥对农田土壤氮素利用和流失的影响 总被引:14,自引:4,他引:10
通过2年在果园和蔬菜田的生产试验及田问氮素流失监测,对比研究常规施肥管理和精确滴灌施肥技术在作物产量、肥料消耗量和农田氮素流失负荷等方面的差异,分析不同施肥方式对农田土壤氮素利用和流失的影响.结果表明:滴灌施肥技术把定量的溶解态肥料直接输送到作物根部,提高了肥料利用效率,农作物产量与常规产量基本持平甚至略有提高,而氮肥消耗量和氮素流失负荷则显著降低.与常规施肥管理方式相比,2006年梨、大豆和玉米的单位产量氮肥消耗量分别降低10.8、11.8和8.9 g/kg,削减率分别为22.8%、26.6%和30.8%;单位产量总氮流失量也分别削减45.2%、14.5%和26.3%.2007年梨、西瓜和玉米的单位产量氮肥消耗量分别降低11.1、8.1和5.0 g/kg,削减率分别达到29.7%、65.8%和21.5%;单位产量总氮流失量分别削减56.4%、49.7%和51.8%. 相似文献
167.
Massimo Saccomani Piergiorgio Stevanato Daniele Trebbi J. Mitchell McGrath Enrico Biancardi 《Euphytica》2009,169(1):19-29
Beta vulgaris genetic resources are essential for broadening genetic base of sugar beet and developing cultivars adapted to adverse environmental
conditions. Wild beets (sea beets, B. vulgaris spp. maritima and their naturalized introgressions with cultivated beets known as ruderal beets) harbor substantial genetic diversity that
could be useful for beet improvement. Here, we compared molecular and morpho-physiological traits of wild beets collected
on the Adriatic coast of Italy with sugar beet using eight primer-pairs amplifying 194 polymorphic fragments and four root
traits (glucose and fructose content in the root tip, root elongation rate, number of the of root tips, total root length
and its distribution among diameters ranges). Genetic diversity was higher in the sea beet accession, which may be due to
the highly variable selection pressures that occur in heterogeneous ecological niches, compared with the ruderal and cultivated
beets. Sea and sugar beet accessions showed contrasting root patterns in response to sulfate deprivation: sugar beet showed
an increase of reducing sugars in the root tips and higher root elongation rate, and the sea beet accession showed an increase
in root tip number, total root length and fine root length (average diameter < 0.5 mm). The ruderal beet showed intermediary
responses to sea and sugar beet accessions. AFLP and morpho-physiological cluster analyzes showed sea, ruderal and cultivated
beets to be genetically distinct groups. The results of this study indicate variability in response to sulfate deprivation
is present in undomesticated beets that could be deployed for sugar beet improvement. 相似文献
168.
Spadavecchia C Spadavecchia L Andersen OK Arendt-Nielsen L Leandri M Schatzmann U 《American journal of veterinary research》2002,63(11):1551-1556
OBJECTIVES: To evoke and measure the nociceptive withdrawal reflex (NWR) by use of electromyographic recordings and to score the behavioral nociceptive responses to electrical pulses in standing nonsedated horses. ANIMALS: 10 adult horses. PROCEDURE: The lateral palmar digital nerve of the forelimb was transcutaneously stimulated, and surface electromyographic responses were recorded from the ulnaris lateralis, extensor carpi radialis, and common digital extensor muscles. Stimuli consisted of a 25-millisecond train of 5 constant-current pulses delivered by a computer-controlled stimulator. The 80- to 250-milliseconds poststimulation interval was analyzed to detect the NWR. The current intensity was increased in steps of 0.5 mA until the NWR threshold intensity (lt) was reached. The stimulus at It was repeated twice. Latency and amplitude of the NWR, together with the behavioral reaction of horses, were analyzed. The latter was scored according to a scale from 0 (no reaction) to 5 (vigorous reaction). Finally, 3 suprathreshold stimuli at 1.2 X It were analyzed. RESULTS: The median It to elicit NWR was 2.5 mA. Median onset latency of the NWR was 96.0 milliseconds at It and 89.6 milliseconds for suprathreshold stimuli. The amplitude of the reflexes was higher for suprathreshold stimulations, and behavioral reactions were slightly stronger when stimulus intensity increased. CONCLUSIONS AND CLINICAL RELEVANCE: Results of our study indicate that it is possible to record NWR in conscious standing horses, to define a reflex threshold, and to measure reflexes in response to increasing stimulus intensity. 相似文献
169.
Marialuisa Carmellino Gabriella Massolini Massimo Pregnolato Giuseppe Pagani 《Pest management science》1990,28(1):1-6
Some 3′- or 4′-alkylthio-2-iodobenzanilides and some 3′-alkylthio-2-methylbenzanilides were tested in vitro and in vivo against fungal plant pathogens of different taxonomic classes and some showed activity, especially in vivo. Among all the tested compounds the 3′-alkylthio-2-iodobenzanilides revealed the highest activities. 相似文献
170.
Massimo Zaccardelli Francesco Campanile Annalisa Spasiano Massimo Merighi 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(3):299-306
The development of a rapid detection method for Xanthomonas campestris pv. campestris (Xcc) in crucifer seeds and plants is essential for high-throughput certification purposes. Here we describe a diagnostic
protocol for the identification/detection of Xcc by PCR amplification of fragments from the pathogenicity-associated gene
hrcC. Under stringent conditions of amplification, a PCR product of 519 bp from hrcC was obtained from a collection of 46 isolates of Xcc, with the exception of two isolates from radish. No amplicons were obtained
from 39 pure cultures of the phytopathogenic bacteria Xanthomonas campestris pv. cerealicola, X. campestris pv. juglandis, X. campestris pv. pelargonii, X. campestris pv. vitians, X. arboricola pv. pruni,
X. axonopodis pv. phaseoli, X. axonopodis pv. vesicatoria, X. vesicatoria, Pseudomonas syringae pv. phaseolicola, P. syringae pv. syringae, P. syringae pv. tomato, P. fluorescens, P. marginalis, Pectobacterium atrosepticum, P. carotovorum subsp. carotovorum. In addition, PCR reactions were negative for fifty unidentified environmental isolates purified from the surface of crucifers.
The PCR fragment was obtained from four strains previously classified as X. campestris pv. aberrans, X. campestris pv. armorociae, X. campestris pv. barbarae and X. campestris pv. incanae using pathogenicity assays. Our PCR protocol specifically detected Xcc in inoculated leaves, seeds and naturally infected
leaves of crucifers. 相似文献