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1.
In the mid-1970s, a new apple variety named ‘Meran’ was discovered in South Tyrol (northern Italy), which harbours the largest continuous apple growing area in Europe. The cultivar was registered for varietal protection and patented in several countries, and was declared to be a cross of the varieties ‘Golden Delicious’ and ‘Morgenduft’ (synonym ‘Rome Beauty’). The parentage of ‘Meran’ has, however, been questioned, and the present study aimed to assess the descent of this cultivar by the combined use of molecular genetic and bioinformatic tools. Five accessions of ‘Meran’ were collected from three different European germplasm collections and analysed at 14 variable microsatellite DNA loci. Subsequently, computer software was used to allocate the most likely parent pair from a set of cultivars representative for the apple growing area of South Tyrol in 1975. The molecular genetic data clearly excluded ‘Morgenduft’ as a gene donor to ‘Meran’ and provided strong evidence that ‘Meran’ is a cross of the cultivars ‘Golden Delicious’ and ‘Jonathan’, confirming previous assumptions based on morphological traits of the tree and fruit.  相似文献   

2.
Poysean (Euphorbia × lomi Rauh) has been introduced in the Mediterranean countries as an ornamental plant for indoor uses. When used outdoor, few information is available about its ability to withstand the Mediterranean temperature extremes. An experiment in an open stand was performed to evaluate poysean tolerance to the winter and summer temperatures of the thermo Mediterranean climate and its ornamental value for urban greening. Two genotypes of poysean (Nguen Muang, NM; and Soi Budsanin, SB) with similar bracts and flower colours were grown at either 2 or 3 plants per pot during 23 months. Number of flower racemes and leaves per plant and plant height were recorded monthly. Overall ornamental value of each pot was scored by means of a panel test (PT) performed by independent examiners. Score assignment was homogeneous between examiners. On average, NM showed a 36% lower number of flower racemes, but a 30% higher ornamental value than SB. During fall and beginning of the winter, NM showed a higher number of flower racemes per plant than SB. Increasing plant density from 2 to 3 plants per pot did not influence flower racemes and leaves per plant. From March to November of the second year, number of flower racemes in NM was similar to the first year, whereas SB flower production was markedly higher, which can be due to a genotypic difference to Mediterranean temperature tolerance. Correlation between number of flower racemes per pot and ornamental value was higher in SB than NM, which suggest that in NM flower abundance contribute less to the pot ornamental value. The present data suggest that poysean is able to withstand the Mediterranean temperature extremes and still produces flower racemes during winter, which indicate it as a suitable ornamental plant in outdoor applications.  相似文献   

3.
Summary

Temperature regimes that induce and ameliorate cropping troughs (“thermodormancy”) were evaluated over two seasons for the everbearing strawberry ‘Everest’. When plants were exposed to 26°C for 5, 10, 20 or 30 d in July, heat-induced troughs in cropping were observed in August. An important discovery was that cool (13°C) night temperatures ameliorated the severity of thermodormancy. In this study, thermodormancy appeared to be due principally to flower abortion post-anthesis, as large numbers of flowers emerged in mid-July, during the high temperature treatments, but went on to produce low fruit numbers in mid-August. Flower initiation itself (monitored by crown dissection) was not reduced by high temperatures. The observation that night-time temperature is critical for thermodormancy has significance for commercial production, in which protected cropping tends to increase average temperatures throughout the season, and venting tends to focus on day-time temperatures.  相似文献   

4.
In Central Europe vast wetland areas have been converted into agricultural land over the past few centuries. Long-term spatially explicit reconstructions of wetland cover changes at regional scale are rare but such information is vital for setting appropriate wetland conservation and restoration goals. In this study wetland cover change over the past 150 years was analyzed for the Canton Zurich (Switzerland) using information from historical and current topographical maps. Mapping instructions changed significantly over time, i.e., wetlands were mapped more conservatively on older maps. Therefore a technique was developed to account for changes in mapping instructions and to reconstruct a series of comparable maps spanning 1850–2000. Wetland cover dramatically decreased from 13,759 ha in 1850 (more than 8% of the total study area) to 1,233 ha in 2000 (less than 1%). Largest loss is observed for the first half of the twentieth century when more than 50% of the total wetland loss occurred. In 1850, almost all wetland patches were connected in two large networks defined by a 500 m buffer around all wetland patches to account for typical dispersal distances of wetland animals. Despite extensive wetland loss, this networks remained largely intact until 1950, but then collapsed into many medium and small networks consisting of only few wetland patches. In addition to the direct loss of wetland habitats increased habitat fragmentation is limiting metapopulation dynamics and hindering genetic exchange between populations. Amphibians and other wetland animals are particularly prone to habitat fragmentation because of their limited migration abilities. This may lead to time-delayed extinction in the future because current species occurrence might rather reflect historical than current wetland cover and habitat configuration. Future restoration efforts should focus on reestablishing connectivity between remaining smaller wetland networks.  相似文献   

5.
Consumer demand for food diversity ,andtechnological developments in the domesti-cation and cultivation of edible mushrooms ,have ledto a continuous increaseinthe numberof cultivated mushroom varieties . Zhudugu(Chinese commercial name) is one of severalnewly cultivated species that has gainedpopularity in both domestic and overseasmarkets . The cultivated strain was originallyisolated froma wild mushroomby the SanmingInstitute of Fungi ,Fujian Province , initiallymisidentified asClitocybe i…  相似文献   

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7.
This study was carried out in Arsin (Trabzon/Turkey) in 2011. The effects of different harvest time and altitudes on the quality of the nuts have been investigated. The study was performed on Fo?a hazelnut and the harvest process has been conducted at three terms, which are on normal harvest time and ten days before and after harvest time. The harvested nuts were dried in the shade on the concrete floor until their moisture content decreased to 5?%. Some properties of nuts including yield, fruit weight, internal weight, shell thickness, and protein, oleic, and linoleic acid amounts have been investigated. As evaluated all of the fruit properties it can be concluded that 11 August is the most suitable harvest date for coast zone. On the other hand, no significant differences were obtained in the point of protein, oleic, and linoleic acid amounts for different harvest time and altitudes.  相似文献   

8.
The Hexa-Hives illustrate how an outdoor live installation (landscaped garden installation) can serve as incentive for inter-species encounters and at the same time challenge the paradigm of conventional beekeeping. The Hexa-Hive is an experimental hive, designed to both host honeybees and serve as outdoor furniture for humans. Since 2012, the Hexa-Hive has been a semi-permanent installation in Kaisaniemi Botanic Garden of Helsinki.A further development, the Hexa-Hive Village was first installed at the campus of Aalto University, in Otaniemi, Finland in 2013. Launched as artistic intervention, the Hexa-Hive village became a landscaped area hosting honeybees and inviting people to hang out.In 2014, a further development - the installation “Hexa-Hive Village with Airstrip for Bees” - was exhibited as part of the art exhibition “Semi-Wild Gardens” at Kouvola city art museum and in 2016, the installation was placed in Tarja Halonen Park, a public area in the centre of Helsinki.The article explores the effects of the installation assessed via a questionnaire. The findings include the emergence of a “garden quality” around the “Hexa-Hive”, the increase of local faunal and floral diversity and the notion of wilderness in the city. The concept of urban acupuncture and the mental and psychological value of public gardens for humans are described as features of the installation.The Hexa-Hive is part of Melliferopolis and was launched in Helsinki in 2012. The activities comprise exhibitions, workshops, installations and lectures.www.melliferopolis.net  相似文献   

9.
AIM:To investigate Nrf2 that regulates the expression of γ-glutamylcysteine synthetase (γ-GCS) in the inflammatory cells in bronchial asthma guinea pig bronchoalveolar lavage fluid (BALF). METHODS:Adult male guinea pigs were randomly divided into control group (group A), asthmatic group (group B) and dexamethasone group (group C). Asthmatic model was established by the method of ovalbumin challenge. MDA concentration in the lung tissue homogenate was detected. The total cell count and the proportion of inflammatory cells in BALF were measured. The methods of immunohistochemistry and in situ hybridization were used for detection of the protein and mRNA expressions of Nrf2, Bach1 and γ-GCS. RESULTS:(1) The proportion of eosinophils (EOS) in BALF and the MDA concentration of the lung tissue in group B were higher than those in group A and group C. (2) The result of in situ hybridization indicated that the A value of γ-GCS was the highest in group A compared to group B and group C, but the A value of Nrf2 and Bach1 in 3 groups has no statistical significance. (3) Immunohistochemistry indicated that the A value of γ-GCS in group B was lower than that in group A. The positive rate in cell nucleus of Nrf2 in group B was lower than that in group A and group C. The positive rate in cell nucleus of Bach1 in group B was higher than that in group A and group C. (4) The mRNA expression of γ-GCS (A value) showed positive correlation with the positive rate in cell nucleus of Nrf2 and negative correlation with the positive rate in cell nucleus. A negative correlation between the proportion of EOS in BALF of group B and the γ-GCS mRNA was observed. CONCLUSION:There is disequilibrium between oxidation and anti-oxidation in bronchial asthma guinea pig. Inflammatory reaction decreases the expression of γ-GCS in the inflammatory cells in bronchial asthma guinea pig. Dexamethasone regulates the nuclear translocation of Nrf2/Bach1 and increases the expression of γ-GCS.  相似文献   

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11.
The ongoing effects of the climate emergency and the recognition of the need to redesign cities to cope with future socio-environmental changes and increase the quality of life of urban inhabitants has pushed many cities to embrace the ‘re-naturalization’ of public space through Nature-based Solutions (NbS). Les Glòries park (Barcelona) is an ongoing massive urban transformation project that incorporates NbS as a multifunctional tool. It attempts to respond to complex environmental, social, and economic urban problems while at the same time mitigating and adapting to hazards, such as floods and droughts, both predicted to increase in the Mediterranean region due to climate change. While NbS are also expected to improve environmental quality, not much attention has been given to how those strategies would intersect with citizens’ expectations and visions of public space and the uneven socio-environmental relations they can enforce. Through a case of urban development of a new large green area in Barcelona, this article aims to discern different perceptions by the local community and planners on the socio-ecological role of NbS and the implications this has for sustainable urban transitions. In-depth interviews were held with 25 key stakeholders and users, complemented by the analysis of secondary data from the town council of Barcelona about the perception of the space by residents living in the surrounding neighborhoods of the park. The results of this paper show that perceptions around NbS are strongly divided into three groups: the believers, the opposers and the skepticals. These results contribute to nuance NbS, as they do not provide universal benefits, neither for nature nor for society, and that they are subject to urban tensions derived from inequities, conflicts, tradeoffs, and particularly from divided visions of what the ‘re-naturalization’ of cities should look like.  相似文献   

12.
13.
We argue for the landscape ecology community to adopt the study of poverty and the ecology of landscapes as a Grand Challenge Topic. We present five areas of possible research foci that we believe that landscape ecologists can join with other social and environmental scientists to increase scientific understanding of this pressing issue: (1) scale and poverty; (2) landscape structure and human well-being; (3) social and ecological processes linked to spatial patterns in landscapes; (4) conservation and poverty, and (5) applying the landscape ecologist’s toolkit. A brief set of recommendations for landscape ecologists is also presented. These include the need to utilize broad frameworks that integrate social and ecological variables, build capacity to do this kind of work through the development of strong collaborations of researchers in developed and developing countries, create databases in international locations where extreme poverty exists, and create a new generation of researchers capable of addressing this pressing social and environmental issue.  相似文献   

14.
Landscape Ecology - Linear landscape elements (LLEs) such as ditches and hedgerows can increase the ecological connectivity of habitat embedded within agricultural areas by acting as corridors for...  相似文献   

15.
We examined the connection between landscape characteristics and behaviour of a long-distance migratory raptor. Our main goal was to test whether long-distance migratory birds adjust their migration programme according to the different characteristics of the habitats crossed during the journey with special emphasis in the so-called “ecological barriers”, inhospitable environments such as deserts, ice fields, seas and mountain ranges, where the opportunities to fulfil energy requirements are low or absent and environmental factors could be extremely severe. To this end, 11 Eleonora’s falcons were tracked by satellite telemetry in their ca. 9000 km autumn migration route from colonies located in Western Mediterranean to their wintering grounds in Madagascar during 2007 and 2008. Our results show that Eleonora’s falcons migrated during day and night-time, adjusting migration speed and daily distance in relation to the crossed region. Unlike other migrant species, Eleonora’s falcons did not avoid ecological barriers by making unnecessary detours around them or converging on narrow corridors. Nocturnal migration and higher daily distances were observed when flying across the Sahara Desert and the Mozambique Channel. The circadian pattern of activity budget shows that Eleonora’s falcon relies on an internal navigation mechanism that works during both day and night. Finally, our results suggest that the Sahara is an ecological barrier not only for passerines but also for raptors migrating within the Palaearctic-African flyway.  相似文献   

16.
Summary

Bitter pit fruit in commercial consignments of apples still poses an economic threat to exporters from South Africa. Mineral analysis of fruit has been used with variable success to predict bitter pit prior to harvest. The possibility of increasing the accuracy of existing predictive models by using analysis of individual fruit rather than pooled samples was investigated. By improving the normality of the distributions of the different minerals and decreasing the overlap between pitted and non-pitted fruit classes, we attempted to improve the reliability of predictions based on variable threshold values. Even though our model produced a correct classification of 85% for non-pitted fruit which can be useful, this was still below the required tolerance expected on the market which, at present, is less than 2% bitter pit in an overseas consignment. The classification for pitted fruit, 63%, was not satisfactory.  相似文献   

17.
Summary

The effects of low temperatures on subsequent vegetative growth and flowering in the raspberry ‘AutumnBliss’ were investigated. In the first experiment, a number of lifting dates were used to determine the seasonal pattern of dormancy and the effect of natural chilling on plant development. In the second, different durations of artificial chilling(0, 2, 4, 6, 8 and 10 weeks at 0?C) were combined with two lifting dates to investigate the effect of natural and artificial chilling. In these experiments, plants which received little chilling grew slowly and failed to develop beyond short rosettes of leaves but as chilling increased, the rate of vegetative growth increased. This coincided with a decline in the time toflowering. These two responses, however, were distinct. In a third experiment, the effect of vernalization of actively growing canes was tested in an attempt to separate the effects of cold on time to flowering, and on the removalof dormancy. The plants responded significantly to cold treatment and flowering was advanced, indicating a distinct vernalizing effect  相似文献   

18.
Two ecological models have been put forward to explain the dynamics of fire-promoting and fire-sensitive vegetation in southwest Tasmania: the alternative stable states model of Jackson (in Proc Ecol Soc Aust 3:9–16, 1968) and the sharpening switch model of Mount (in Search 10:180–186, 1979). Assessing the efficacy of these models requires high resolution spatio-temporal data on whether vegetation patterns are stable or dynamic across landscapes. We analysed ortho-rectified sequences of aerial photography and satellite imagery from 1948, 1988 and 2010 to detect decadal scale changes in forest and non-forest vegetation cover in southwest Tasmania. There was negligible change from forest to non-forest (<0.05%) and only a modest change from non-forest to forest over the study period. Forest cover increased by 4.1% between 1948 and 1988, apparently due to the recovery of forest vegetation following stand-replacing fire prior to 1948. Forest cover increased by 0.8% between 1988 and 2010, reflecting the limited ability of forest to invade treeless areas. The two models include interactions between vegetation, fire and soil, which we investigated by analysing the chemical (phosphorus, nitrogen) and physical properties (clay, silt) of 128 soil samples collected across 34 forest–non-forest boundaries. Phosphorus in the upper horizon was typically lower in non-forest vegetation compared to forest vegetation, which is consistent with proposed fire–vegetation–soil feedbacks. Mineral horizons were dominated by sand, with low levels of clay under all vegetation types. Available field evidence lends support to the Jackson (1968) alternative stable states model as the most suitable model of vegetation dynamics on nutrient poor substrates in southwest Tasmania although modifications of the timeframes for transitions toward rainforest are required.  相似文献   

19.
Through a quantitative approach, this study aimed to clarify the changes in the number of visitors and visits to green spaces according to green space type before and after the COVID-19 pandemic. We explored the changes in the proportion of repeat visitors and the distance between green spaces and visitors’ places of residence. We used KDDI Location Analyzer, which performs novel analysis using mobile phone GPS and census data. The study area included 10 target sites (urban parks and nature trails in the backcountry) located in the Sapporo metropolitan area in Japan. The survey period included snow-free seasons from 2019 to 2021, and 2019 was considered the period “before the pandemic.” The results revealed that the number of visits during the pandemic increased compared with those before the pandemic, except for those of urban parks near the city center. In 2020, the proportion of repeat visitors increased for all 10 target sites. In addition, since the outbreak of the pandemic, distances between all urban parks and visitors’ residences decreased. The same trend was observed for nature trails in the backcountry close to the city center. These findings indicate a generally decreasing trend in the number of visits to green spaces as many people have been refraining from visiting the site since the outbreak of the pandemic. Contrastingly, the number of visits by repeat visitors who reside close to the target sites has increased in some cases, which compensated for the general decreases.  相似文献   

20.
6-Benzyladenine (BA) showed only a slight thinning effect which was probably correlated with low temperatures during application. It is concluded that under the current climate of the Lower Elbe region temperature is a more important factor than fruit size for determining the time-point of BA application. Ethephon at 300?ppm produced a stronger effect, even if this was still insufficient in the present case. Higher concentrations (450–600?ppm) are required for strongly flowering ‘Elstar’ plantations older than 4?years, but this invokes the risk of excessive thinning. Therefore, the application of Ethephon requires a high degree of experience on part of the fruit farmer. Metamitron, applied once at 350?ppm, showed similar effects to Ethephon. An enhanced effect might have been obtainable if a second treatment had been applied some 10?days later. No phytotoxic damage was observed. Metamitron would be an interesting fruit thinning agent and should be considered for registration in Germany. Naphthalene acetic acid (NAA) and NAA + BA gave the best results in the experiment for 2006?described here. It is not yet clear whether the degree of flowering for 2007 will be influenced in a similarly positive manner as for Ethephon. Since NAA and Metamitron have not been registered for Germany, their practical use cannot be recommended.  相似文献   

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