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51.
The profit of fruit producing enterprises in Saxony-Anhalt as well as in whole Germany has continually improved during the last years. This concerns the profit as well as the profitableness, the solvency and the economic stability of the enterprises. Especially related to the profitableness the enterprises do not reach the target amount. Therefore it must be object, to rise the profitability in the long run and to pay off all factors of production in order to guarantee long-term solvency and economic stability.  相似文献   
52.
The effects of modified atmosphere packaging (MAP) [bioriented polypropylene (BOPP-1 or BOPP-2)] in combination with antimicrobial agents Bacillus subtilis, 107 colony-forming units (cfu) ml−1; ethylenediamine tetraacetic acid, calcium disodium salt hydrate (EDTA) (0.1%); or 4-hexylresorcinol (4-HR) (0.15%) on postharvest decay control and quality retention of litchi cv. McLean's Red were assessed as possible replacements for commercial SO2 fumigation. Fruits dipped in B. subtilis, EDTA or 4-HR (5 min) separately, blow dried (25 °C, 3 min), packed in BOPP-1, held for 18 d at 2 °C, 95% RH, and 2 d at 14 °C, 75% RH were significantly less decayed. The antagonist–BOPP-1 combination also promoted the best bacterial survival during storage. B. subtilis was observed to survive effectively in BOPP-1 (16% O2, 6% CO2; 90% RH), but its survival was adversely affected in BOPP-2 (5% O2, 8% CO2; 93% RH). Alternaria alternata and Cladosporium spp. were the major decay-causing fungi in BOPP-1 treatments, and Candida, Cryptococcus and Zygosaccharomyces were the predominant yeasts in BOPP-2 treatments. Combination treatments EDTA, 4-HR or B. subtilis in BOPP-1 inhibited polyphenol oxidase (PPO) and significantly reduced pericarp browning and severity. Although the combination treatments EDTA, 4-HR or B. subtilis in BOPP were equally effective in controlling decay and browning, the EDTA and 4-HR affected the natural pinkish-red colour of the pericarp by showing higher h° values (orange–pink). Among the combination treatments, B. subtilis+BOPP-1 had the best potential to control decay, retain the colour and the overall litchi fruit quality during a marketing chain of 20 d.  相似文献   
53.
Eva Johansson 《Euphytica》2002,126(1):143-149
Variation in falling number, amylase activities, protein concentration and composition were investigated in two wheat cultivars grown in Sweden over two seasons, in four locations, with four N fertilizer rates, with and without fungicide treatment. The results showed that;
•  Tarso had higher falling number, amylase activities, protein concentration and amount of most protein components compared to Kosack.
•  The environment (year, location, N rate and fungicide treatment) influenced falling number, alpha amylase activities, and protein concentration and composition.
•  Two processes were related to low falling numbers; late maturity leading to poor starch and protein quality and excessive rains leading to break-down of starch and proteins.
•  Poor starch and protein properties influenced the bread-making quality to a higher extent than break-down of starch and proteins.
This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
54.
Symbiotic gene mutated in the pea (Pisum sativum L.) line RisfixC is a determinant of the number of symbiotic root nodules. In parallel to a sharp increase in nodule number, its mutational inactivation brings about the insensitivity of nodulation to the ambient nitrate level (Nts trait). Using the established localization to the SYM2-NOD3 region of the pea linkage group I, functional PCR markers were developed for the orthologous region on the chromosome 5 of the model species Medicago truncatula. Owing to the conservation of the binding regions of the designed primers, pea orthologues were successfully amplified with 60% of the primer pairs tested. When applied to a mapping pea population from the cross of the line RisfixC x Afghanistan L1268 (sym2), the new markers allowed to localize the supernodulation mutation within 2.5 cM confidence interval in the pea genome. The placement of the functional markers on the M. truncatula chromosome 5 confined the orthologous gene location to eight overlapping BACs spanning approximately 710 kbp (positions 37,755,678–38,467,472). The narrowed list of the annotated Medicago genes in combination with the published data on their symbiotic and nitrate regulation can be used for the candidate gene identification, together with the requirements imposed by the known function in nodule number initiation and nitrate sensing. In addition, the new markers are applicable for tracking the RisfixC allele in breeding programmes aimed at the improvement of symbiotic performance.  相似文献   
55.
Because of the relative dearth of scientific information in agroforestry, monitoring and evaluation of agroforestry technologies in development projects plays an important role in the development and improvement of technical extension recommendations. To identify appropriate methodologies, ICRAF conducted in 1988–89 a review of agroforestry technology monitoring and evaluation in 166 projects worldwide, of which 108 responded. Almost 80% of these were involved in technology evaluation. Many extension projects were conducting research to test technologies on-farm or on research plots. Technology evaluation by projects focused on the biological of trees, often with inadequate consideration of the technology context. Few projects seemed to use farmer assessment in evaluation. Recommendations are made for an effective evaluation process and selection of appropriate methods and variables to be assessed by projects. Methods should be selected according to the availability of resources and should favour collaborative or collegial interaction between farmers and project staff.  相似文献   
56.

• Introduction  

The abandonment of rural areas has led to an increase of the fire-prone European gorse (Ulex europaeus L.) communities in some regions, where prescribed burning is a technique applied to control them. Understanding flammability changes after treatments is crucial for the sustainable use of fire.  相似文献   
57.
Macleaya cordata (plume poppy) is used in traditional Chinese medicine for its anti-inflammatory and antibacterial activities. In this study, we examined whether M. cordata extract and/or its major alkaloid constituents, protopine, allocryptopine, sanguinarine and chelerythrine activate the Nrf2 signalling pathway which regulates the expression of cytoprotective enzymes including heme oxygenase-1 (HO-1) and thioredoxin 1. In murine macrophage RAW264.7 cells, M. cordata extract increased both mRNA and protein levels of HO-1. Of the alkaloids examined, only sanguinarine appeared to be responsible for these effects. At the concentration of 2 μM, sanguinarine induced nuclear accumulation of Nrf2, increased the expression of Hmox1 gene encoding HO-1 and elevated HO-1 protein levels. Sanguinarine-induced Hmox1 mRNA expression was suppressed by SB203580, a pharmacologic inhibitor of p38 mitogen-activated protein kinases (p38 MAPKs). The upregulation of HO-1 in RAW264.7 cells by sanguinarine was, however, accompanied by decrease in cell viability. Nonetheless, sanguinarine at micromolar, non-cytotoxic concentrations elevated protein levels of HO-1 and thioredoxin 1 in primary cultures of human hepatocytes. We conclude that sanguinarine may, under appropriate conditions, increase the capacity of the enzymatic antioxidant defence system via activation of the p38 MAPK/Nrf2 pathway.  相似文献   
58.
Properties of individual trees can be estimated from airborne laser scanning (ALS) data provided that the scanning is dense enough and the positions of field-measured trees are available as training data. However, such detailed manual field measurements are laborious. This paper presents new methods to use terrestrial laser scanning (TLS) for automatic measurements of tree stems and to further link these ground measurements to ALS data analyzed at the single tree level. The methods have been validated in six 80 × 80 m field plots in spruce-dominated forest (lat. 58°N, long. 13°E). In a first step, individual tree stems were automatically detected from TLS data. The root mean square error (RMSE) for DBH was 38.0 mm (13.1 %), and the bias was 1.6 mm (0.5 %). In a second step, trees detected from the TLS data were automatically co-registered and linked with the corresponding trees detected from the ALS data. In a third step, tree level regression models were created for stem attributes derived from the TLS data using independent variables derived from trees detected from the ALS data. Leave-one-out cross-validation for one field plot at a time provided an RMSE for tree level ALS estimates trained with TLS data of 46.0 mm (15.4 %) for DBH, 9.4 dm (3.7 %) for tree height, and 197.4 dm3 (34.0 %) for stem volume, which was nearly as accurate as when data from manual field inventory were used for training.  相似文献   
59.
60.
Stands of quaking aspen (Populus tremuloides) rank among the most biologically diverse plant communities across the intermountain region of western North America. Marked declines of aspen have occurred in recent decades, likely due to a combination of effects from changes in fire regimes, herbivory, climate (e.g. drought), and interspecific competition with conifer species. However, it is poorly understood how the effects of these factors are manifested at a landscape scale over decadal time periods. Analysis of field data combined with topographic information collected across the 500,000 ha Owyhee Plateau in southwestern Idaho revealed that aspen in the area occur in three different biophysical settings; First, aspen stands exist at high altitudes on south-facing slopes where local conifer species are not likely to occur because of limiting temperature or precipitation levels under current climate conditions. In these areas aspen is the potential vegetation type rather than conifers. Second, aspen grow on anomalously wet microsites (e.g. near springs), and third, aspen grow within upland mixed aspen/conifer stands, which are experiencing rapid rates of conifer establishment. Based on a paired t-test (α = 0.05) we conclude that stands growing on wet microsites show significantly slower successional rates of conifer establishment relative to upland aspen stands. We developed a conceptual state-and-transition model for upland aspen/conifer stands occurring across a range of topographic positions. We then parameterized the model using extensive field data in the vegetation dynamics computer simulation model Vegetation Dynamics Development Tool (VDDT), and examined the current and future aspen distribution under varying fire regimes. Model results indicate that average fire return intervals of 50–70 years are desirable for maintenance of aspen in upland areas where conifers are present. Under the current fire regime in the area many upland aspen/conifer stands will likely be lost within 80–200 years. Thresholds for the effect of conifer encroachment and browsing on aspen regeneration identified through this research are similar to those described by others across the West. We therefore suggest that the results presented for the Owyhee Plateau are likely applicable to semi-arid aspen woodlands across the American West where succession to conifers is a cause of aspen decline.  相似文献   
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