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The aim of the work was to study changes in the yield and nutritional characteristics of whole crop semi-leafless field pea over two growing seasons in the Po plain, Italy. Samples of two cultivars (Baccara and Sidney) were collected from flowering to grain maturity. The developmental stage, yield, dry matter (DM) content, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), starch, water soluble carbohydrates (WSC), gross energy (GE), organic matter digestibility (OMD) and the net energy for lactation (NEL) were determined at each harvest. The forage characteristics were regressed on the growing degree days (GDD) with 4.4 °C as the base temperature. The DM yield increased with advancing maturity from 0.5 to 8.91 Mg ha−1, while the CP decreased from 261 to 159 g kg−1 DM. During the whole growth cycle the GE, OMD, NEL and milk forage units (milk FU) were almost steady. No differences were observed between the cultivars for any of the measured parameters. At grain maturity, the crop produced over 4.0 Mg ha−1 DM of grain. The CP, starch and WSC of the grain did not show any differences between the cultivars or years. The data showed that the nutritive quality of the forage of the semi-leafless grain pea harvested as a whole crop for ensiling purposes did not diminish with maturity and could help improve the self-sufficiency of dairy farms, in terms of home-grown protein forages. 相似文献
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Schiavi Daniele Francesconi Sara Bischetti Giulia Giovanale Geremia Fortunati Elena Balestra Giorgio Mariano 《植物病害和植物保护杂志》2022,129(1):181-187
Journal of Plant Diseases and Protection - Bacterial spot caused by Xanthomonas euvesicatoria pv. euvesicatoria (Xanteu) is one of the major causes of yield losses in tomato (Lycopersicon... 相似文献
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Bonazzi M Volta A Gnudi G Bottarelli E Gazzola M Bertoni G 《Journal of Feline Medicine and Surgery》2007,9(5):387-391
The ultrasonographic findings of kidneys, liver and urinary bladder of 288 Persian and 44 Exotic Shorthair clinically normal cats that underwent screening for polycystic kidney disease (PKD) between July 2003 and December 2005 were reviewed. Cats were divided into two groups, one including cats aged <9 months (group 1) and one cats aged >/=9 months (group 2). Cats were classified as PKD-positive when at least one renal cyst was found. One hundred and thirty-six cats (41.0%) had more than one cyst in at least one kidney. The prevalence of PKD was similar in both groups. Eight PKD-positive cats had cystic livers (5.9%). Other renal abnormalities included a pelvic calculus and a medullary rim sign (MRS). The difference in prevalence of an MRS in group 2 compared to group 1 and the difference between PKD-positive and -negative cats in group 2 were not significant. There was no difference in mean kidney length between PKD-positive and -negative cats in group 2. Urinary bladder anomalies were principally represented by urinary sediment, with prevalence significantly higher in group 2. No difference was detected in group 2 between PKD-positive and -negative cats. In conclusion feline PKD is common in Italy. The ultrasonographic findings of MRS and urinary bladder sediment did not correlate with feline PKD. Urinary bladder sediment is common in Persians and Exotic Shorthairs and more likely in adults. 相似文献
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Response of forest soil properties to urbanization gradients in three metropolitan areas 总被引:2,自引:0,他引:2
Richard V. Pouyat Ian D. Yesilonis Katalin Szlavecz Csaba Csuzdi Elizabeth Hornung Zoltan Korsós Jonathan Russell-Anelli Vincent Giorgio 《Landscape Ecology》2008,23(10):1187-1203
We investigated the effects of urban environments on the chemical properties of forest soils in the metropolitan areas of
Baltimore, New York, and Budapest. We hypothesized that soils in forest patches in each city will exhibit changes in chemistry
corresponding to urbanization gradients, but more strongly with various urban metrics than distance to the urban core. Moreover,
differences in parent material and development patterns would differentially affect the soil chemical response in each metropolitan
area. Results showed that soil chemical properties varied with measures of urban land use in all three cities, including distance
to the urban core, which was an unexpected result. Moreover, the results showed that the spatial extent and amount of change
was greater in New York than in Baltimore and Budapest for those elements that showed a relationship to the urbanization gradient
(Pb, Cu, and to a lesser extent Ca). The spatial relationship of the soil chemical properties to distance varied from city
to city. In New York, concentrations of Pb, Cu, and Ca decreased to approximately background concentrations at 75 km from
the urban core. By contrast, concentrations of these elements decreased closer to the urban core in Baltimore and Budapest.
Moreover, a threshold was reached at about 75% urban land use above which concentrations of Pb and Cu increased by more than
twofold relative to concentrations below this threshold. Results of this study suggest that forest soils are responding to
urbanization gradients in all three cities, though characteristics of each city (spatial pattern of development, parent material,
and pollution sources) influenced the soil chemical response. 相似文献
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Multivariate approach to evaluate the penetrometer resistance in different tillage systems 总被引:1,自引:0,他引:1
At present, the penetrometer is the most widely used instrument for assessing in situ soil strength, one of the extrinsic factors affecting plant growth and crop productivity. In this paper we propose a method that discriminates penetrometer resistance due to different soil treatments, by means of Principal Component (PC) analysis. We hypothesized and demonstrated that penetrometer resistance values measured at different soil depths are correlated among themselves (multicollinearity). Considering measurements at each depth as different variables, PC analysis restructured data sets containing these correlated variables into a smaller number of components, whose scores were utilized in univariate analysis of variance (ANOVA) to test differences among imposed soil treatments. We applied the procedure to penetrometer resistance values measured by means of a hand-held cone penetrometer in two long-term experiments conducted in southern Italy, on durum wheat (Triticum durum Desf.) under continuous cropping. In the first trial, four different soil tillage treatments were compared; in the second, two different tillages and two residue management systems were examined. In both trials, PC analysis reduced the original 14 depths of measurements into only 4 PC's, based on correlations of their resistance values, explaining more than 80% of the total variation. Furthermore, ANOVA applied to the scores of each PC, clearly indicated treatment effects on soil strength.
The proposed method has thus allowed assemblage a posteriori of penetration resistance data into only a few significative intervals, using correlations among the measurements made at the different depths. This way, the possible resistance differences due to tillage and/or management treatments have been more easily and more unambiguously showed. 相似文献