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1.
This paper investigates club convergence in per capita income across 81 NUTS‐III regions in Turkey over the 1987–2017 period using the procedure suggested by Phillips and Sul. Based on a nonlinear factor model that allows for transitional heterogeneity, our econometric approach enables us to test the presence of convergence clusters and to examine their transitional behavior. We obtain strong evidence that there is no absolute or conditional convergence but convergence clubs across Turkish regions: five clubs in the first period covering 1987–2001 and six clubs in the second period covering 2004–2017. The geographical distribution of clubs suggests a clear separation between the eastern and the western regions of Turkey for both periods. While geography may be destiny, results from an ordered logit model reveal that initial income per capita, human capital, and total credits are the most important determinants of convergence clubs in Turkey.  相似文献   

2.
The study investigated the cultivars of non‐obligatorily requiring vernalization plant Festulolium braunii and assessed the influence of non‐hardy reproductive and hardy vegetative structures on overwintering effect. The study was conducted taking into account systemic relations between these types of structures. The results show the cultivars differ according to the percentage of headed and overwintered plants, when the cultivars with the most abundant heading – ‘Felopa’ and ‘Sulino’ – are also better at overwintering. The positive correlation between heading and overwintering characteristics was also observed, what seemed to be a rather new finding. It can be explained by systemic effect: non‐hardy later reproductive structures induce the post‐generative regrowth of vegetative shoots, which during shorter days halt development and become potentially hardy. More detailed interpretation is also provided including discussion of causal mechanisms of the detected phenomenon. The authors suppose that these mechanisms constitute a survival strategy for such perennial plants. The observed late heading which represents reproductive structures could be applied in plant breeding as a marker of winter‐hardiness among perennial grass plants which non‐obligatorily demand vernalization.  相似文献   

3.
The creation of a public–private research partnership between plant breeding industry and academia can be beneficial for all parties involved. Academic partners benefit from the material contributions by industry and a practically relevant research focus, while industry benefits from increased insights and methodology tailored to a relevant set of data. However, plant breeding industry is highly competitive and there are obvious limits to the data and material partners are willing and able to share. This will usually include current and historic released cultivated materials, but will very often not include the elite germplasm used in-house to create new cultivars. Especially for crops where hybrid cultivars dominate the market, parental lines of hybrid cultivars are considered core assets that are never provided to outside parties. However, this limitation often does not apply to DNA or genetic fingerprints of these parental lines. We developed a procedure to take advantage of elite breeding materials for the creation of new promising research populations, through indirect selection of parents. The procedure starts with the identification of a number of traits for further study based on the presence of marker-trait associations and a priori knowledge within the participating companies about promising traits for quality improvement. Next, regression-based multi-QTL models are fitted to hybrid cultivar data to identify QTLs. Fingerprint data of parental lines of a limited number of specific hybrids are then used to predict parental phenotypes using the multi-QTL model fitted on hybrid data. The specific hybrids spanned the whole of the sensory space adequately. Finally, a choice of parental lines is made based on the QTL model predictions and new promising line combinations are identified. Breeding industry is then asked to create and provide progeny of these line combinations for further research. This approach will be illustrated with a case study in tomato.  相似文献   

4.
The article aims at discussing the rise of the green bonds in the context of the multilateral development banks, by problematizing their threats and potentialities to be an alternative to the existing financing system within the sustainable development agenda. It scrutinises the development rhetoric behind the emergence of multilateral development banks in the Global South, specifically in the Asian context, and attempts to foster alternatives to the Bretton Woods institutions. The two largest initiatives in that sense – the New Development Bank and the Asian Infrastructure Investment Bank – started in Asia and also target countries in the region, giving the growing influence of China and the enhancement of interregional cooperation through the BRICS countries, currently led by China, India and Russia. The paper argues that there is limited scope for the promised innovations in both project assessment and the role of private capital, given the prioritisation of infrastructure as the premise to achieving the right to development among emerging and least‐developed economies. The research departed from the quantitative and qualitative analysis of the projects funded by the New Development Bank and the Asian Infrastructure Investment Bank, from their inception until 2018, considering the approach that such institutions have taken to the social and environmental standards from their normative framework.  相似文献   

5.
Recent technological advances in UAV (unmanned aerial vehicle) technology offer new opportunities for assessing agricultural plot experiments using UAV imagery. Vegetation indices (VIs) based on aerial images derived from consumer-grade cameras are a simple and cheap alternative compared to VIs derived from proximal (on-ground) sensors. The objective of this study was to assess whether VIs derived from consumer-grade cameras mounted on UAVs are reliable and whether there are any shortcomings in image acquisition and analysis that need to be addressed before their general application. This objective was investigated using a rotary-wing and a fixed-wing UAV, true colour (RGB) and colour-infrared (CIR) cameras, four different VIs (ExG, NGRDI, NDVI and ENDVI), altitudes in the range of 30–100 m, different ambient lighting conditions and two different software packages for stitching images together. Results were compared with ground-based recordings by consumer-grade cameras and multispectral sensors. Field experiments in cereals were used to evaluate the assessments. The study showed that VIs based on UAV imagery have the same ability to quantify crop responses to experimental treatments as ground-based recordings with cameras and advanced sensors. However, there are shortcomings that need to be taken into consideration: (1) angular variation in reflectance (bidirectional reflectance), (2) stitching and (3) ambient light fluctuations. Bidirectional reflectance was so extensive that it could lead to misleading conclusions in sunny conditions and this effect could be amplified further by stitching. A procedure for avoiding impacts from bidirectional reflectance is demonstrated when plots were cropped from individual images and a procedure is suggested for stitching images. Camera, VIs and image acquisition altitude were of minor importance, but fluctuating ambient lighting conditions is an issue that should be addressed in future studies.  相似文献   

6.
Climate change education (CCE) can be an important tool to increase local community resilience. In 2017, the Pacific Community ratified the Framework for Resilient Development in the Pacific (FRDP) aiming to equip local communities with skills needed to become more climate change resilient. In 2018, Fiji implemented the Climate Change Resilience Programme (CCRP) at the University of the South Pacific (USP), the first of its kind in the South Pacific. This paper evaluates (i) the orientation and aim of the programme and (ii) how different stakeholders influenced the curriculum development process. Tribe's concept of curriculum space is used to highlight the overall aim of the CCRP. Freeman's stakeholder theory allows to identify key stakeholders and their influence on the curriculum. Results indicate that the programme seems to foster climate resilience in the workplace rather than the local community. Unfortunately, current and future community leaders, the notional targets of this course, were almost completely unrepresented in the process to accredit the course, with the body responsible for accreditation being dominated by industry representatives. This study helps to inform the current review of the Regional Certificate Programme to realign it with its initially envisioned community focus.  相似文献   

7.
Huib Ghijsen 《Euphytica》2009,170(1-2):229-234
Today the free access to germplasm for breeding purposes is becoming more and more limited by two different developments: the patenting of traits and varieties on the one hand and the evolution with regard to access and benefit sharing in the convention on biological diversity (CBD) and the international treaty for plant genetic resources of food and agriculture (IT-PGRFA) on the other hand. Patents are generally more restrictive regarding research and breeding than plant breeder’s rights in which the important notion of the breeder’s exemption in the laws based on the international union for the protection of new varieties of plants. Conventions provides free access to commercialized, protected plant varieties for further commercial breeding. This breeder’s exemption is limited by the notion of essential derivation: closely bred “essentially derived varieties” (EDV’s) need for the purpose of commercialization the permission of the owner of the protected initial variety where the EDV has been derived from. New traits, from natural or artificial sources, can be protected by patents. The plants containing a patented trait do fall under its patent protection. In the USA conventional varieties can also be patented, which is not possible in most other countries in the world. This patent system allows claims on the progenies resulting from crossing patented plants with other plants. As each new variety consists of a unique combination of existing characteristics and crossing this variety with plants of other varieties yield new combinations, the ownership of a particular variety should not extend to the progenies of the crossing parents. The CBD and IT-PGRFA treaties subject the access to germplasm to particular rules for benefit sharing, whereby the terms for access under the CBD are still to be established and the outcome of the present negotiations is very uncertain. On top of these developments private companies use increasingly Material Transfer Agreements and restrictions printed on seed bags to limit the access to commercial varieties for breeding purposes. The question arises whether this tightening straitjacket will benefit or harm the breeding of new varieties in the long run and how the breeders in the field (will) cope with these developments.  相似文献   

8.
Organic growers need information on variety performance under their growing conditions. A 4-year onion variety research project was carried out to investigate whether setting up a variety testing system combining conventional and organic variety trials is feasible and efficient rather than organizing separate variety trials under the two management systems. During 4 years commercial onion cultivars were tested at a certified organic and a non-organic location. Both systems were managed without chemical pest, disease and sprouting control, but differed in fertility management (organic manure in autumn versus synthetic fertilizer), soil cultivation and weed management (mechanical weeding versus application of herbicide). Management system significantly affected plant density, thickness of neck, and proportion of small and large bulbs. Variety × management system interactions were significant for bulb uniformity, earliness, proportion of large bulbs, dormancy and relative storage success but did not change the ranking of the varieties. We conclude that organic growers can profit from a more conscious variety choice when conventionally fertilised trials would refrain from using pesticides, fungicides, herbicides and sprout inhibitors. However, this would require an adaptation of the management protocol in such a way that trials might no longer represent conditions of conventional farmers. Furthermore, assessments of leaf erectness, disease resistance to downy mildew and leaf blight should be included in the protocols for organic use. We advocate better communication between breeders and growers on specific variety characteristics contributing to improving yield stability under low-input, organic growing conditions.  相似文献   

9.
One hundred and four released varieties of bread wheat (Triticum aestivum L ssp. aestivum) in India were crossed to two T. aestivum L ssp. aestivum testers, namely, C306 (Ne 1 Ne 1 ne 2 ne 2 ) and HD2329 (ne 1 ne 1 Ne 2 Ne 2 ) to determine the frequency and distribution of genes for hybrid necrosis present in them. Sixty-seven varieties (65.4 %) showed the presence of Ne 2 gene and only eight varieties (7.7 %) had Ne 1 gene in their background. Twenty-nine varieties (27.9 %) were non carrier (ne 1 ne 1 ne 2 ne 2 ) for both the genes. Most of the Ne 1-carriers are of Indian origin and their pedigree revealed the involvement of landraces and old varieties as parents. Predominance of Ne 2 gene in Indian varieties happened after the introduction of semi-dwarf Mexican wheat varieties, which are mostly Ne 2 carriers and also due to the extensive and continuous use of germplasm from Mexican and European origin in the hybridization programme. Moreover varieties with Ne 2 gene is selected for their linked beneficial traits mainly rust resistance genes. The phenomenon of hybrid necrosis is one among the post zygotic barrier speciation process which acts as a barrier for either intra or inter specific gene flow. The genetic architecture of hybrid necrosis in wheat is simple following the minimal predictions of the Bateson–Dobzhansky–Muller model. Widespread occurrence of dominant genes for hybrid necrosis in Indian varieties is of great concern to wheat breeders as it often interferes in the choice of elite parents and imposes restrictions on the productivity of crosses.  相似文献   

10.
Planned resettlement is being widely considered as a response to the impacts of climate change. As many millions of people are expected to be displaced in the coming decades, scholars and policymakers are searching for precedence to inform their research and planning, particularly from experiences of Development‐Induced Displacement and Resettlement (DIDR). Nowhere in the world is DIDR and other closely related forms of planned resettlement more prevalent than in China: an estimated 78 million people have been displaced by development projects over the last six decades. While planned resettlement has consistently been shown to cause impoverishment, the Chinese state views it as the answer to a multitude of social ills including poverty, environmental damage, low levels of domestic consumption, and most recently, climate change, providing impetus to the normalisation of resettlement as adaptation. This paper examines the prospects for just outcomes in resettlement projects by examining distributive justice at multiple scales in existing resettlement practice in China. It finds that due to the interplay between resettlement and questions of procedural justice, prospects for just outcomes are quite limited, and that in order to achieve fair adaptation, alternatives to planned resettlement should be emphasised.  相似文献   

11.
Barley is one of the most popular crops in dryland agricultural systems of Mediterranean areas, where it is assumed that barley, or traditional wheat cultivars, performs better than modern wheat under low‐yielding conditions. It was tested whether variations in net leaf photosynthetic rate (PN) during grain filling provide any basis for the potential better performance of barley and traditional wheat compared to modern wheats in Mediterranean areas. Two groups of field experiments were conducted in Agramunt (NE Spain) during 2005/06 (06) and 2006/07 (07) growing seasons combining low and high nitrogen (N) availabilities under rain‐fed and irrigated conditions. Cultivars used in the first group of experiments were a traditional (Anza) and a modern (Soissons) wheat, whilst in a second group of experiments, a wheat (Soissons) and a barley (Sunrise) modern cultivars were used. Both wheat cultivars showed a similar PN during grain filling but higher than that of the modern barley cultivar. Differences between species in PN were maximized under high‐yielding conditions. There were no differences between cultivars in instantaneous water‐use efficiency. The barley cultivar showed a higher specific leaf area, but lower N content per unit of leaf area, than wheat. Photosynthetic nitrogen‐use efficiency was similar between the traditional and the modern cultivar but lower than barley. Decreases in PN after anthesis were not exactly observable in SPAD measurements. In conclusion, we found no consistent differences between cultivars in terms of post‐anthesis photosynthetic activity to support the assumption of better performance under Mediterranean farm conditions of traditional wheat or barley against modern wheat.  相似文献   

12.
As part of the Thai Government's objective to increase energy security through biodiesel, oil palm was introduced to Northeast Thailand in 2005. Nong Khai Province was selected as a pilot project because of its suitable environmental conditions. This study assesses the acceptance of policy interventions and socio‐economic conditions by adopters and non‐adopters. We found that total farmland size was significantly higher among oil palm producers than among non‐producers. Nevertheless, the area under oil palm cultivation did not increase in accordance with land size in the way rubber did. Oil palm and non‐oil palm farmers had almost equal amounts of rice area thereby providing household food security. Oil palm did not replace food crops. Farmers investing in oil palm tend to base their livelihood around on‐farm production, whereas non‐adopters tend to diversify with off‐farm income sources. Oil palm was found to be one component of a diversified farming system and an additional income source, albeit not the primary one. In conclusion, oil palm was a crop that had been tried by (wealthier) farmers with sufficient capital, and an aim to further diversify on‐farm household income. Oil palm is certainly not (yet) contributing substantially to household income in Thailand's Northeast.  相似文献   

13.
This paper analyses the structural change in small‐island economies—sometimes labeled offshore financial centers (OFCs)—that have seen wealth‐generating activities through offshore financial services decrease in value since 2008. At the same time, OFCs have come under increasing scrutiny from supranational organizations such Organization for Economic Co‐operation and Development and European Union for perceived unfair tax practices and money laundering activities. Some OFCs have proactively adjusted to this sea change by broadening the economic base through development of new offshore business activities such as e‐gaming, film industry, and niche manufacturing. Most have increased co‐operation with onshore regulatory bodies to promote service and product legitimacy. Econometric analysis explores the assertion that OFCs that do not have a political link to the onshore may be exposed to greater capital inflows volatility than OFCs that have such a link. Case study analysis using the theoretical lens of evolutionary economic geography illustrates that a small OFC is creating spatialities of economic novelty by adapting economic development strategies deployed during the successful development of the center prior to the recent recession. Our findings reveal the importance of political links to the onshore to reduce capital inflow volatility and the importance of local public–private interaction to legitimize post‐recession development.  相似文献   

14.
The aim of this article is to discuss and substantiate new spaces for the political participation of migrant civil society at the regional level in Southeast Asia through the lens of the Association of Southeast Asian Nations (ASEAN) Forum on Migrant Labour (AFML). The AFML process is shaped by the International Labour Organisation and mirrors its tripartite format, essentially bringing together governments, employers’ and workers’ organisations. Crucially, migrant support and self‐organisations also have access, even if somewhat restricted, to regularly held deliberations. In light of the ASEAN consensus on migration that was agreed upon at the end of 2017, the article situates the AFML within the ongoing process of migration governance in the region and focusses especially on the role of migrant civil society as an important stakeholder. Based on the specific experience of civil society organisations (CSOs) from Malaysia, the article discusses which spaces the forum provides for civil society actors and how the latter use them for their advocacy. The major argument of the article is that the development of migration policies at the regional level can benefit from the inclusion of migrant civil society in the process. The governance of migrants could thus be complemented by governance for and by migrants.  相似文献   

15.
M. N. Ogburia    T. Adachi  T. Yabuya 《Plant Breeding》2000,119(2):191-192
Histologically, the cassava pistil is trilocular with a single ovule in each locule producing a maximum of three seeds in nature. Heat stress (35°/45°C, night/day temperatures), as a physical treatment was attempted to induce useful reproductive and vegetative traits in 10 F1 hybrids derived from ‘OMR 36‐41’and ‘OMR 36‐42’crosses, and two Asian cassava cultivars,‘Rayong 60’and ‘Rayong 1′, under greenhouse and field conditions. Cytoembryological examination of the repro‐ ductive organs revealed morpho‐structural features of normal pistil in all clones except ‘Rayong 1’which exhibited reproductive variations under greenhouse culture. Genetically, an important variation was ovule dichotomy per locule of the trilocular pistil so that each pistil contained six instead of the usual three ovules and lacked any outer integument. These ovules possessed functional embryo sacs with varying nuclear number. A pair of the dichotomous ovules possessed two embryo sacs of apparent different megaspore mother cells. Vegetatively, F1 hybrids were dwarf (0.50m) in their phenotype and flowered 1 month earlier than the 1.5‐2.0m tall cultivars under greenhouse conditions.  相似文献   

16.
The importance of reactive oxygen species (ROS) in plant defense responses against certain pathogens is well documented. There is some evidence that microbial biocontrol agents also induce a transient production of ROS in a host plant which triggers local and systemic defense responses to pathogens. The ability of biocontrol agents used to control postharvest diseases to induce defense-related oxidative responses in fruits, however, has not been explored. Here we show that the yeast antagonists, Metschnikowia fructicola (strain 277) and Candida oleophila (strain 182) generate greater levels of super oxide anion (O2) on intact fruit surfaces (poor in nutrients) then those applied on a nutrient-poor agar medium. Even though yeast antagonists show a high level of O2 on nutrient-rich media, when applied on fruits around wounds (areas abundant in nutrients) accumulation of O2, as detected by nitro blue tetrazolium staining, occurred much more rapidly on the latter. Using laser scanning confocal microscopy we observed that the application of M. fructicola and C. oleophila into citrus and apple fruit wounds correlated with an increase in H2O2 accumulation in host tissue. In citrus fruit, the level of H2O2 around inoculated wounds increased by 4-fold compared to controls (wounds inoculated with water) as early as 18 h after inoculation. Yeast continued to stimulate H2O2 production in citrus fruit up to 66 h after inoculation and H2O2 levels were still 3-fold above the control. Living yeast cells were detected in fruit wounds at this time point indicating the ability of M. fructicola to tolerate host ROS, which has been reported to be an intrinsic characteristic of efficient yeast antagonists. Similar increase in H2O2 accumulation around yeast-inoculated wounds was observed in apple fruit exocarp. The present data, together with our earlier discovery of the importance of H2O2 production in the defense response of citrus flavedo to postharvest pathogens, indicate that the yeast-induced oxidative response in fruit exocarp may be associated with the ability of specific yeast species to serve as biocontrol agents for the management of postharvest diseases.  相似文献   

17.
The interest in organic grown cereals has increased the need for variety tests under organic growing systems and/or the knowledge on whether growth characteristics describe yield differently under conventional and organic conditions. This paper is a contribution to that question by examining the relationships between some important growth characteristics in barley trials in both systems in Northern Sweden and in Denmark. Mixed model analyses were used for regressions of growth characteristics (or transformations of those) on yield (and log-transformed yield), allowing the slope to depend on the growing system. The analyses showed that diseases seemed to have a less negative effect on yield in the organic growing system than in the conventional growing system if pesticides were not applied. For other characteristics the effect depended on the country. This was the case for grain characteristics where the effect of volume weight in the Swedish trials was much larger in the conventional growing system than in the organic growing system, while a non-significant difference in the opposite direction was found for the trails from Denmark. For the trials from Denmark the effect of grain weight was much larger in the organic growing system than in the conventional growing system, but there was only a small and non-significant difference in the Swedish trials. In both countries there was a significant interaction between the two grain characteristics.  相似文献   

18.
The Wadden Sea is important as a stop-over and wintering area for several species of waders, foraging for shorter or longer times on its tidal flats. The size of the food stocks these birds encounter varies from place to place and from year to year. We studied characteristics of the variability in time of such prey stocks, using long-term data series of annual estimates of biomass of macrobenthic animals collected on tidal flats in various parts of the Dutch and German Wadden Sea. Year-to-year fluctuations were stronger in nearly all individual benhos species than in total macrozoobenthic biomass. The various species differed significantly in their year-to-year variability. Everywhere the tellinid bivalve Macoma balthica was relatively stable, whereas species such as the cockle Cerastoderma edule and the polychaetes Lanice conchilega, Nephtys hombergii and Anaitides mucosa fluctuated heavily and rapidly in all parts of the Wadden Sea where they were found. Within species, fluctuations in biomass of individual age or size classes were stronger than those in total biomass of the species.Several species showed minimal biomass values in the same years over vast areas. This synchronization of scarcity was caused particularly by similar responses to winter character, which was each year similar over the entire Wadden Sea. Such similar responses included low over-winter survival during severe winters and recruitment failure after exceptionally mild winters. Immediately after severe winters, such cold-sensitivee species as C. edule, L. conchilega and N. hombegii were scarce all over the Waden Sea, thus liimiting the possibilities for birds to switch to other parts of the Wadden Sea to find their preferred prey in sufficient quantitu. Simultaneous recruitment failure in several important bivalve species (C. edule, Mytilus edulis, and Mya arenaria limited the possibility for specialized bivalve consumers to switch to alternative prey types in certain years.  相似文献   

19.
The benefits of improving nitrogen use efficiency (NUE) in crops are typically studied through the performance of the individual crop. However, in order to increase yields in a sustainable way, improving NUE of the cropping systems must be the aim. We did a model simulation study to investigate how improvement of NUE traits of individual crops affects the succeeding crops and the NUE of the crop rotation. Based on experimental results parameterization was altered for different types of improved NUE in the EU-Rotate_N model, e.g. through higher N harvest index, reduced litter loss or improved root depth penetration rate. The different ways of improving NUE have different effects on the cropping system, affecting either N uptake, the ability of the crop to hold on to N already taken up, or the fraction of crop N being harvested. Due to the different modes of action, the model simulations show that these changes in NUE traits will also have different effects on N leaching loss and on N availability and N loss in the following years. Simulations also show that the effect of genotypes with improved NUE depend on environment and crop management. This is true for the improved crop itself and when its effect is analyzed for the whole cropping system. The environmental conditions, crop choices and management will all affect the fate of the N left in the soil, and whether this will contribute mainly to leaching loss or be used for production in later crops. As an example, increasing pre-crop fertilization was shown to affect the leaching after the following oilseed rape crop with up to 50 kg N ha?1 taken up before it was lost to the environment when pre-crop fertilization as well as root depth penetration rate was high. All in all, the simulations illustrate the concept of NUE as the result of interactions between genotype, environment and crop management (G×E×M).  相似文献   

20.
Vietnamese ‘blue boats’ – small wooden‐hulled fishing boats – are now entering the territorial waters of Pacific Island countries and illegally catching high‐value species found on remote coastal reefs. Crossing several international boundaries and traversing a distance of over 5000 km, these intrusions have alarmed Oceanic countries, including Australia. Lacking administrative capacity as well as jurisdictional authority to effectively control the vast stretches of island coastlines individually, governments and intergovernmental bodies in the region have called for strengthened coordination of surveillance efforts while also pressuring Vietnam diplomatically. This paper reviews these latest developments and is the first to provide a focused assessment of the issue. Through the lens of Copenhagen School of securitisation theory, we analyse responses of national and regional actors and their portrayal in online media to understand how blue boats are constructed as a security threat within a narrative of maritime, food and human security. Arguably, Australia together with the Forum Fisheries Agency, who advise on the governance of offshore tuna resources, have so far acted most decisively – in a way that might see them extend their strategic role in the region. We propose a comprehensive empirical research agenda to better understand and manage this nascent, flammable and largely unpredictable inter‐regional phenomenon.  相似文献   

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