采后热处理对苹果贮藏性影响及病虫害控制的研究进展

采后热处理作为近年快速发展的贮藏保鲜技术,已经应用于多种水果的采后品质与病虫害控制方面。苹果是当今世界上重要的水果之一,热处理在苹果贮藏保鲜方面已得到较为深入的研究。介绍了采后热处理的各种方法及其组合,着重阐明了采后热处理对果实贮藏期间病虫害的控制。此外还探讨了热处理对苹果化学成分、外观品质、成熟衰老、耐热性等方面的影响以及相关作用机制。最后对热处理不当有可能产生的热伤害作了论述。     

Warm Storage of Narcissus Bulbs in Relation to Growth,Flowering and Damage Caused by Hot-Water Treatment

Three experiments are described on the effects on flowering of warm storage of narcissus bulbs before (and in some cases after) hot-water treatment (h.w.t.) against eelworm infection. Almost complete loss of the flower crop occurs if the bulbs are not warm stored, compared with the production of about 90% marketable flowers following warm storage. Optimum temperatures and durations of warm storage are not clearly defined; there is very little difference between the two recommended treatments, 34° C. for 3 days and 30° C. for 7 days, with the latter giving slightly better results. In another experiment, best results were obtained following 32·5° C. for 8 days or 35° C. for 5 days, with some varietal differences. These combinations were superior to most at 30° C., and to all of only 2 days duration. Higher temperatures and longer durations generally result in earlier flowering, with no adverse effect on flower quality. Bulb yield in the field following h.w.t. is higher when the bulbs are warm-stored before h.w.t. and, when forced in the following season, they give more flowers. Post-h.w.t. warm storage reduces flower quality and bulb yield in the field; although some minor benefits were observed, this treatment cannot be recommended. The possible mechanism for the protection afforded by warm storage is discussed.     

三种霉菌对生姜茎腐病的防效测定

试验利用哈茨木霉(Trichoderma harzianum)、绿色木霉(Trichoderma viride)和青霉(Penicillium spp.),采用菌丝体生长速率法和盆栽试验,测定了它们对生姜茎腐病(Pythiummyriotylum)的防治效果。结果表明:3种霉菌中青霉对生姜茎腐病的防治效果表现最佳,哈茨木霉次之,其室内抑菌率分别为50.97%和55.23%;盆栽防效分别高达74.83%和61.9%,显著高于绿色木霉,显示出了较高的开发应用价值。     

Experiments on the Control of Brown Rot of Apples and Plums: I. Laboratory Tests

The symptoms and some properties of five viruses isolated from celery crops in Britain are described. Cucumber mosaic and lucerne mosaic viruses were found to be prevalent in celery and other crops. Tomato aspermy virus, though widespread in chrysanthemum and occasional in tomato crops in England, and economically damaging in Continental celery crops, has not so far been reported in celery in Britain. British celery varieties tested were resistant to experimental infection with tomato aspermy virus. These three viruses were readily isolated, purified and identified.

Three viruses, designated celery yellow spot, celery yellow vein and celery ringspot, isolated from affected celery plants, were less readily transmitted from celery to celery, and could not be purified by techniques that succeed with many viruses.

Celery yellow spot was transmitted by sap-rubbing inoculation only when cucumber mosaic virus was also present ; it was tentatively identified with the celery yellow spot virus reported from the U.S.A. Celery ringspot virus showed some similarities to the poison hemlock ringspot virus found in the U.S.A., but none of the critical tests for virus identification could be applied to either of these two viruses. Celery yellow net virus differed from all the viruses so far recorded in celery. The chronic symptoms of the different viruses in celery were often similar, and therefore unreliable for diagnosis. The initial or “ shock ” symptoms, however, were usually distinctive.     

不同熏蒸剂处理防治黄瓜根结线虫效果及经济效益分析

选用93%1,3-二氯丙烯乳油(EC)、62%1,3-二氯丙烯胶囊、42%威百亩水剂(AS)、98%棉隆微粒剂(MG)、99%硫酰氟原药(TC)、93%1,3-二氯丙烯EC+98%棉隆MG、93%1,3-二氯丙烯EC+42%威百亩AS防治黄瓜根结线虫,以98%溴甲烷为对照。结果表明:不同熏蒸剂对根结线虫均有良好的防治效果。各熏蒸处理黄瓜产量均显著高于不施药对照,以50g·m-298%溴甲烷处理产量最高,其次为9g·m-293%1,3-DEC+25g·m-298%棉隆MG、9g·m-293%1,3-DEC+21g·m-242%威百亩AS;混用的溴甲烷替代品与溴甲烷相比,经济效益更好。9～18g·m-293%1,3-DEC、9～18g·m-262%1,3-D胶囊和25～50g·m-299%硫酰氟TC处理也有很好的增产效果和良好的经济效益。     

Studies of the Physiologically-Active Volatile Organic Compounds Produced by Fruits : II. The Rate of Production of Carbon Dioxide and of Volatile Organic Compounds by King Edward VII Apples in Gas Storage,and the Effect of Removal of the Volatiles From the Atmosphere of the Store on the Incidence of Superficial Scald

The present method of controlling superficial scald of apples in gas storage by wrapping them in paper containing oil is usually very effective but is costly. This is mainly because it requires so much labour. It also takes time and delays the closing of the store. Can simpler, equally effective methods be found ? It was expected that removal of part of the volatile vapours given off by the apples, by circulating the storage atmosphere through a gas-mask type of filter, would reduce scald. This expectation was based on the theory that scald is caused by the accumulation of one or more of these volatiles in the storage atmosphere. Suitable filters were developed and experiments in which the storage atmosphere was analysed showed that these filters did remove a very large part of the apple volatiles. Nevertheless, it was found that the amount of scald occurring on unwrapped King Edward VII apples in gas storage was almost the same in a store with filters as in one without.

The well-known effect of gas storage in lowering the rate at which apples lose CO₂ is shown in the present paper by means of diagrams. It is this condition which is responsible for the extension of storage life of apples in gas mixtures.     

Assessment of joint soil ecosystem services supply in urban green spaces: A case study in Northern Italy

The multiple functions of urban soils secure the supply of ecosystem services to the urban population, but they are seldom taken into account in current urban planning. The purpose of this study is to highlight the multifunctionality of the soils of urban green spaces and to assess the influence of different types of urban green (i.e. parks and gardens, roadside green and agricultural fields) on the joint supply of soil-based ecosystem services. In a case study area in the city of Carpi (NE Italy), we focused on a set of soil functions underpinning ecosystem services and on possible synergies and trade-offs between them. We surveyed and sampled 19 urban green areas to assess the following soil functions: biological fertility, potential habitat for organisms, water regulation and storage, soil buffering capacity and carbon stock. Results showed differences and trends in the bundles of ecosystem services provided by the soils of urban green areas, highlighting the relevance of soil disturbance and vegetation cover density in affecting soil functions. For biological indicators, results showed a negative significant correlation to CaCO₃ content, which is associated with the degree of soil disturbance, and that soils in urban areas do not always have compromised soil fauna and may provide the same level of biological quality as agricultural soils or forests.     

利用有机质防治黄瓜枯萎病

采用室内抑菌测定及盆栽防治试验相结合的方法,测定了12种有机物对黄瓜枯萎病发生及其对黄瓜植株生长的影响。结果表明,12种有机物浸提液对黄瓜枯萎病菌菌丝均有一定的抑制作用,以菇渣和鸡粪的抑菌效果较好,分别为48.35%和47.85%;盆栽试验以菇渣、壳粉、鸡粪及芝麻饼对黄瓜枯萎病的防效较好,接种后的防效分别为100.0%、83.8%、78.8%和62.0%,且菇渣和鸡粪对黄瓜植株的生长具有明显的促进作用。     

Linking demand and supply factors in identifying cultural ecosystem services of urban green infrastructures: A review of European studies

Urban green infrastructure provides a number of cultural ecosystem services that are greatly appreciated by the public. In order to benefit from these services, actual contact with the respective ecosystem is often required. Furthermore, the type of services offered depend on the physical characteristics of the ecosystem. We conducted a review of publications dealing with demand or social factors such as user needs, preferences and values as well as spatially explicit supply or physical factors such as amount of green space, (bio)diversity, recreational infrastructure, etc. and linking demand and supply factors together. The aim was to provide an overview of this highly interdisciplinary research, to describe how these linkages are being made and to identify which factors significantly influence dependent variables such as levels of use, activities or health and well-being benefits. Commonly used methods were the combination of questionnaires with either on-site visual recording of elements or GIS data. Links between social and physical data were usually established either by using statistical tools or by overlaying different thematic maps. Compared to the large number of variables assessed in most studies, the significant effects in the end were relatively few, not consistent across the studies and largely dependent on the context they were seen in. Studies focused on aesthetic and recreational services, while spiritual, educational and inspirational services were not considered when creating links to spatially explicit ecological structures. We conclude that an improvement and harmonization of methodologies, cross-country studies and an expansion of this line of research to a wider range of services and more user groups could help clarify relationships and thereby increase applicability for urban management and planning.     

松尔膜配套药剂对李树流胶病的防治效果

该研究使用四川国光公司生产的松尔膜+松达+国光多菌灵防治李树流胶病。田间对李树流胶病的试验研究表明,使用松尔膜+松达+国光多菌灵处理的病株率为16.67%,对照的病株率为46.67%,防效为64.29%;单位面积流胶点数分别为1.33和6.46,防效为79.41%。说明松尔膜配套药剂对防治和抑制李树流胶病效果较好。     

Exploring the relevance of a landscape ecological paradigm for sustainable landscapes and livelihoods: A case-application from the Northern Territory Australia

Global change is exacerbating the need for more effective mechanisms and approaches for working towards economic, social/cultural and environmental sustainability. It is now well recognised that science for sustainability will require integrated problem-focussed research that is by nature trans-disciplinary. Resolutions to both global and regional scale issues must involve participation of a diverse number of stakeholders. One region that would benefit greatly from such an integrated approach is the Northern Territory of Australia. This area is home to some of the most pristine savanna landscapes in the world and it is also occupied by one of the oldest living human cultures which are still in existence today. However, in recent years there has been increasing pressure to develop this region. The Northern Territory is also facing problems associated with having a growing Aboriginal population with deepening health and social problems. So as well as needing to facilitate adaptation in response to global change and development for economic prosperity of the region, there is an obligation to alter management practices to reduce social disadvantage. In light of this, it will be important that future landscapes are multifunctional and designed to ensure the preservation of biological and cultural diversity, as well as having provision for the livelihoods of the people that live within them. This article recommends the adoption of a landscape ecological approach for strategic development and sustainable planning, which captures and incorporates the values and identities of the different stakeholders, as well as engaging them in a continuous, adaptive process of planning and management, and in doing so discusses the importance of human ecological holism as part of the conceptual framework for landscape ecology.     

Colonization of central European abandoned fields by dry grassland species depends on the species richness of the source habitats: a new approach for measuring habitat isolation

Abandoned fields are perceived as potential habitats for species of threatened semi-natural dry grasslands. However, information is lacking regarding how the spontaneous colonization of abandoned fields depends on the broader spatial context. We recorded the occurrence of 87 target species in 46 abandoned fields and 339 dry grasslands. We tested the effect of the isolation of abandoned fields from source grasslands on the number of dry grassland species occurring in abandoned fields either with or without habitat characteristics being used as covariates. The isolation of the fields was calculated using the distance and area (I _A ) or distance and species richness (I _S ) of source habitats. I _S always explained the number of grassland species in the abandoned fields better than I _A . The effect of isolation became smaller or even non-significant with the inclusion of covariates; it also changed with the method used for measuring distance (edge-to-edge or center-to-center), and it was lower when other abandoned fields were considered as additional source habitats. The different performance of the two isolation measures can be explained by the weak species–area relationship in the grasslands, indicating differences in their habitat quality. Species richness is a better proxy of habitat importance in terms of propagule source than habitat area, and the new isolation measure is therefore suitable for studying the effects of landscape structure on species richness in landscapes presenting a weak species–area relationship, such as areas exhibiting pronounced effects of land-use history. Inclusion of habitat characteristics as covariates may considerably alter conclusions regarding the effect of isolation, which might actually be overestimated when assessed separately.     

Soil Disinfestation with Steam: A Review of Economics,Engineering, and Soil Pest Control in California Strawberry

ABSTRACT

Increasingly stricter fumigant regulations will limit their use and require effective non-fumigant treatments if large-scale strawberry production is to continue in California. Steam has long been used for soil disinfestation in greenhouse soils where it controls most soil pests. The challenge of field-scale soil disinfestation with steam in place of fumigants is availability of machinery capable of treating a large acreage in a timely manner while making the most efficient use of fuel and water. Steam can be a component within an integrated set of fumigant and non-fumigant practices. Steam used together with other practices may permit technically and economically sustainable strawberry production into the future by allowing growers to adapt to more stringent fumigant use restrictions. It may be possible to overcome some of the limitations of steam because steam generator technology has advanced in recent years as well as recent developments in co-applications with steam, including exothermic compounds co-applied with steam and mustard seed meal co-applied with steam. Regarding steam generator technology, direct-fire steam generators are more energy efficient than traditional steam boilers and avoid the hazards of steam pressure vessels. Steam is arguably the most effective non-fumigant method of soil disinfestation and it likely has a role in a future California strawberry production system that is forced to use much less fumigant than it does at present.     

Remote sensing for the assessment of ecosystem services provided by urban vegetation: A review of the methods applied

The study and assessment of ecosystem services through remote sensing has increased substantially over the last two decades, as evidenced by the publication of studies that have applied it. The technological development of satellite images has improved in terms of spatial, spectral, radiometric, and temporal resolution, allowing the space-time observation, classification and monitoring of vegetation on the surface of the Earth. However, there are remaining methodological challenges for assessing ecosystem services due to the diversity of applications, the resources used, and its study in complex environments such as cities. This systematic review is based on identifying and analysing the variety of methods concerning the application of remote sensing for the assessment of ecosystem services provided by vegetation in cities, through a classification of these methods according to the data collection source (passive sensors, passive and active sensors and the fusion of other data sources with sensors). The classification of methods has been applied to a selection of existing articles in indexed scientific databases based on a non-statistical meta-analysis that make a direct reference to the topic of interest. The results show the approaches found in every method classified, their relationships with the geographical scale and the image resolutions used, and the advantages and limitations from the data processes that comprise remote sensing. We conclude from this analysis with three key factors to consider in the selection of remote sensing methods for the assessment of ecosystem services provided by urban vegetation: the definition of the approach(es), the urban scale to be assessed, and the image resolution available.     

A comparison of neighbourhood liveability as perceived by two groups of residents: Tehran,Iran and Tartu,Estonia

Liveability is an important component of the sustainable urban environment, especially in residential neighbourhoods. This study presents a comparison in perceived liveability between residents living in two very different locations, Tehran, Iran and Tartu, Estonia, using a questionnaire survey (n = 102). The image-questionnaire was used to measure residents’ response towards environmental factors and to examine the relationships between the attributes of residential neighbourhoods and perceived liveability. Statistical analyses were performed to analyze the data collected from the survey. The results showed that the neighbourhood liveability was positively influenced by proportion and scale of the spaces, amount of private green areas, street character, amount of public greenery, the variety of building form, the mix of buildings from different periods, perceived crowding and social density. The study demonstrated that residents can assess the factors and that the approach worked in two contrasting locations. The results also showed a great deal of similarity in preference, although this was not the main aim of the study. The approach has potential to be incorporated into participatory urban planning models.