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231.
Synergistic mortality between a neonicotinoid insecticide and an ergosterol‐biosynthesis‐inhibiting fungicide in three bee species 下载免费PDF全文
232.
Andic soils have unique morphological, physical and chemical properties that induce both considerable soil fertility and great vulnerability to land degradation. In recent years there have been many reports of soils with andic properties in Non‐Volcanic Mountain Ecosystems (NVME) in different parts of the world. This paper attempts to assess the importance of andic soils in mountain ecosystems of Italy. We used the criteria of altitude (> 700 m above sea level), slope (< 12°) and active green biomass (maximum Normalized Difference Vegetation Index (NVDI) value > 0.5) for identifying sites where andic soil processes may occur in the NVME of Italy. We characterized in detail 42 soils in the areas thus identified. According to WRB (2006) the main soils are Andosols, Cambisols, Phaeozems, Umbrisols and Podzols. Despite the taxonomic diversity, the morphological, micromorphological and chemical properties indicate considerable pedological homogeneity in these soils. The most striking features are the large values of Alo + 0.5Feo (as %), which is a standard index for andic soil properties ( USDA, 2006; WRB, 2006 ), but it occurs at the wrong depths for many of our soils to qualify as true Andosol/Andisols and there is little evidence of podzolization. We therefore suggest that (i) andic soils must be recognized more clearly in soil classification, particularly with respect to the depths at which andic properties are developed, and (ii) the importance of andic soils in Italian NVMEs (and possibly elsewhere in the world) has been underestimated. These soils warrant further investigation because of their agricultural potential and ecological importance. 相似文献
233.
Coloretti F Chiavari C Armaforte E Carri S Castagnetti GB 《Journal of agricultural and food chemistry》2008,56(23):11238-11244
The combined effect of starter culture, nitrites, and nitrates has been studied in low-acidity salamis, typical products of northern Italy. Nine batches have been prepared, combining three different inoculations of starter cultures (control, Lactobacillus plantarum , and Lactobacillus plantarum together with Kocuria varians ) with three different preservatives (control, sodium nitrate, and sodium nitrite). All of the batches showed a good fermentation process with a proper pH decrease, which was quicker in batches inoculated with L. plantarum. The use of starter cultures and in particular the use of nitrites allowed the control of the proliferation of Enterobacteriaceae and enterococci. The accumulation of biogenic amines, especially putrescine, cadaverine, tryptamine, and tyramine, in salami ready for consumption (60 days of ripening) was strongly affected by the presence of Enterobacteriaceae and enterococci. Results obtained showed that the combined use of adequate preservatives and starter cultures allows the production of safer products with improved sensorial profile. 相似文献
234.
De Angelis M Minervini F Caputo L Cassone A Coda R Calasso MP Divella F Divella F Gobbetti M 《Journal of agricultural and food chemistry》2008,56(18):8619-8628
Criteria for durum wheat quality are continuously evolving in response to market pressure and consumer's preference. Specific attributes of durum wheat for different end products require more rapid and objective means to grade and classify wheat parcels based on processing potential. A total of 10 durum wheat cultivars were compared for compositional, protein, and starch characteristics. Mean values for the gross composition differed for total protein, gluten, and starch. Two-dimensional electrophoresis (2DE) analysis showed the proteome diversity among the cultivars. As shown by the principal component analysis (PCA) applied to 2DE data of gliadin and glutenin fractions, cultivars differed mainly from the number of proteins and levels of protein expression. As determined by the rapid viscoanalyzer (RVA), swelling power, starch damage, amylose content, and starch pasting properties of 10 cultivars differed significantly. 2DE fingerprinting and amylose content seemed to distinguish specific cultivars being useful tools for selecting suitable durum wheat cultivars for pasta making. 相似文献
235.
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237.
Carlotta Balconi Chiara Lanzanova Elena Conti Tiziana Triulzi Fabio Forlani Marzia Cattaneo Elisabetta Lupotto 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(2):129-140
The maize gene b-32, normally expressed in the maize (Zea mays) endosperm, encodes for a RIP (Ribosome Inactivating Protein) characterised by antifungal activity. Transgenic wheat plants
were obtained via biolistic transformation, in which the b-32 gene is driven by the 35SCaMV promoter in association with the bar gene as a selectable marker. Plants were brought to homozygosity through genetic analysis of progeny and pathogenicity tests
were performed on the fourth generation. Six homozygous b-32 wheat lines were characterised. All plants had a normal phenotype,
not distinguishable from the control cv. Veery except for slightly smaller size, flowered and set seeds. Western blot analyses
confirmed b-32 expression during the plant life cycle in the various tissues. Each line differed in the b-32 content in leaf
protein extracts and the transgenic protein expression level was maintained at least up to 10 days after anthesis. Pathogenicity
tests for Fusarium head blight (FHB) were performed on the b-32 transgenic wheat lines in comparison to the parental cv. Veery.
Resistance to FHB was evaluated by the single floret injection inoculation method on immature spikes with spores of Fusarium culmorum. In all the transgenic lines, a similar reduction in FHB symptoms, not dependent on the level of b-32 protein, has been observed
(20% and 30% relative to the control, respectively 7 and 14 days after inoculation). Percentage of tombstone kernels at maturity
was also recorded; in all transgenic lines disease control for this parameter was around 25%. The data obtained indicate that
maize b-32 was effective as in vivo antifungal protein reducing FHB symptoms in wheat lines expressing the maize RIP protein. 相似文献
238.
Two field experiments were carried out at the Experimental Field, Department of Food Science (TE, Italy) in 2004 and 2005 to evaluate the effects of genotypes, different N forms and N rates on yield, safety and nutritional features of processing spinach. Experiment 1, as treatments, included spinach genotypes and N forms (CO(NH2)2; Agricote; NH4NO3); experiment 2 included three N forms (Ca(NO3)2; (NH4)2SO4; NH4NO3) applied at rates of 0, 75, 150, 200 kg N ha−1. This research work confirmed differences among spinach genotypes in terms of efficiency in N use and oxalate and nitrate accumulation. Spinach accumulated much more nitrate in petioles and much more oxalate in blades indicating that nitrate and oxalate might play a counterrole to each other. Fertilizers containing N under forms not readily available to the crop, i.e. Agricote, CO(NH2)2 and (NH4)2SO4, increased nitrate and oxalate accumulations less than fast N-release fertilizers, but their effect on yield was limited. Highest yield with contents of nitrate and oxalate lower than the limits imposed to avoid health problems, were achieved with Ca(NO3)2, at rates of 130 and 150 kg N ha−1 NH4NO3. 相似文献
239.
Jackson PC Meinzer FC Bustamante M Goldstein G Franco A Rundel PW Caldas L Igler E Causin F 《Tree physiology》1999,19(11):717-724
Source water used by woody perennials in a Brazilian savanna (Cerrado) was determined by comparing the stable hydrogen isotope composition (deltaD) of xylem sap and soil water at different depths during two consecutive dry seasons (1995 and 1996). Plant water status and rates of water use were also determined and compared with xylem water deltaD values. Overall, soil water deltaD decreased with increasing depth in the soil profile. Mean deltaD values were -35 per thousand for the upper 170 cm of soil and -55 per thousand between 230 and 400 cm depth at the end of the 1995 dry season. Soil water content increased with depth, from 18% near the surface to about 28% at 400 cm. A similar pattern of decreasing soil water deltaD with increasing depth was observed at the end of the 1996 dry season. Patterns consistent with hydraulic lift were observed in soil profiles sampled in 1995 and 1997. Concurrent analyses of xylem and soil water deltaD values indicated a distinct partitioning of water resources among 10 representative woody species (five deciduous and five evergreen). Among these species, four evergreen and one deciduous species acquired water primarily in the upper soil layers (above 200 cm), whereas three deciduous and one evergreen species tapped deep sources of soil water (below 200 cm). One deciduous species exhibited intermediate behavior. Total daily sap flow was negatively correlated with xylem sap deltaD values indicating that species with higher rates of water use during the dry season tended to rely on deeper soil water sources. Among evergreen species, minimum leaf water potentials were also negatively correlated with xylem water deltaD values, suggesting that access to more readily available water at greater depth permitted maintenance of a more favorable plant water status. No significant relationship between xylem water deltaD and plant size was observed in two evergreen species, suggesting a strong selective pressure for small plants to rapidly develop a deep root system. The degree of variation in soil water partitioning, leaf phenology and leaf longevity was consistent with the high diversity of woody species in the Cerrado. 相似文献
240.
Ronaldo C. PAGLIOSA Rafael DEROSSI Deiler S. COSTA Fabio J.C. FARIA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1339-1345
To test the hypothesis that epidural administration of lidocaine, xylazine or
xylazine plus hyaluronidase provides reduced pain and stress during electroejaculation in
bulls, eight 30-month-old Nellore bulls received saline solution (control), 2% lidocaine,
2% xylazine or 2% xylazine plus hyaluronidase injected into the first intercoccygeal
(Co1–Co2) epidural space in randomized order. Heart rate, respiratory rate, mean arterial
pressure, analgesia, animal behavior and motor blockade were evaluated before treatment
and at predetermined intervals during and after treatment. Pain and stress were scored
subjectively, and semen quality was evaluated. The onset of anesthetic action was
significantly faster with lidocaine (3.0 ± 1.2 min) than with xylazine or xylazine plus
hyaluronidase (8.9 ± 1.5 and 5.5 ± 2.6 min, P=0.021 and
P=0.012, respectively), and the onset of anesthesia with xylazine plus
hyaluronidase was significantly faster than that with xylazine alone
(P=0.032). Treatment with xylazine or xylazine plus hyaluronidase
resulted in less discomfort than treatment with lidocaine, as indicated by animal
behavior. Changes in heart rate, respiratory rate and arterial pressure were within
acceptable limits. Penile protrusion and semen emission occurred in all animals during all
four treatments. Our results suggest that xylazine plus hyaluronidase reduced discomfort
during electroejaculation more effectively than xylazine or lidocaine alone. Further
experiments are necessary to determine whether electroejaculation with xylazine plus
hyaluronidase is feasible for obtaining semen from Nellore bulls unaccustomed to being
handled or restrained. 相似文献