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1.
Bees are in decline potentially leading to reduced pollination and hence production of insect-pollinated crops in many countries. It is however still unclear whether the consequences of pollinator shortages differ among countries with different environmental and societal conditions. Here, we calculated economic gains attributed to insect (particularly bee) pollination (EVIP) as well as their contribution to the total value of crop production (vulnerability), and analyzed their temporal trends and inter-annual variability from 1991 to 2009 for each country of the European Union (EU). To understand which factors drive country-specific differences in pollinator dependency and stability of insect-dependent crop yields, we further asked whether EVIP, vulnerability and stability of yields were influenced by a country's climate, the number of wild bee species and/or managed honeybee hives per country, and (agricultural) gross domestic product (GDP).Across Europe, crop pollination by insects accounted for 14.6 [±3.3] billion EUR annually (EVIP), which equaled 12 (±0.8)% of the total economic value of annual crop production. Gains strongly varied among countries. Both EVIP and vulnerability increased (and the inter-annual variation of vulnerability decreased) significantly from the colder northern to the warmer Mediterranean EU countries, in parallel with increases in the number of wild bee species. Across years, economic importance of pollination increased in all but three EU countries. Apples were the most important insect-pollinated crop in the EU, accounting for 16% of the EU's total EVIP. Our results show that whereas dependency on insect pollination increased from the colder north to the warmer south, variation in economic gain from insect pollination decreased, indicating that Mediterranean countries had more stable yields of pollinator-dependent crops across years and thus more reliable gains from pollination services.  相似文献   

2.
  1. Quantifying the contributions of insect pollinators to crops provides insight into how pollination services should be managed and protected into the future.
  2. Faba bean, Vicia faba var minor (Linneaus), is a widely grown crop globally that can benefit from pollinator visitation, but only from species that are morphologically compatible with the plant's long-corollae flowers. Here, we rank insect pollinators in terms of their potential importance to faba bean pollination and quantify the economic value of pollination for Irish faba beans.
  3. Our findings demonstrate that bee pollination contributes significantly to the pod set of faba beans, and, consequently, the crop's production value. We find that pollination services account for almost half of Ireland's total faba bean market value, with the pollinator contribution estimated at almost €4,000,000 per year.
  4. We estimate that, relative to other pollinators, wild bumblebees contribute to approximately 70% of the economic value of pollination services in faba bean fields, driven mainly by the contributions of a long-tongued bumblebee species, Bombus hortorum (Linneaus; Hymenoptera: Apidae).
  5. Based on these results, we suggest that B. hortorum populations be encouraged on farmland through appropriate management to ensure the continued delivery of pollination services to Irish faba beans.
  相似文献   

3.
中国农业生态系统昆虫授粉功能量与服务价值评估   总被引:1,自引:0,他引:1  
所有开花植物中大约有80%的物种需要动物作为授粉媒介。系统介绍了中国重要栽培作物花的结构和类型,授粉过程、媒介和方式,作物对昆虫授粉的依赖程度,昆虫授粉功能与服务的概念,以及昆虫授粉功能量与服务价值量的评估方法;同时评估了我国各省农业生态系统中昆虫对重要作物的授粉功能量与服务价值量。结果表明:粮食作物、水果作物、蔬菜作物和经济作物不同程度的依赖昆虫授粉。根据2015年主要农作物产量、作物产品价格、昆虫授粉依赖程度等数据,计算得出昆虫对我国22类主要农作物的授粉功能量为1.8亿吨农产品产量和授粉服务价值为8860.5亿元(占当年GDP的1.3%),具有巨大的经济价值。2015年昆虫对主要栽培作物的授粉功能量和服务价值排在前五名的都是山东、河南、河北、陕西和新疆,年授粉服务价值均大于500亿元,反映出这5个省的主要农作物对昆虫授粉依赖程度较高。昆虫对作物的授粉功能量评价有助于了解昆虫对作物生物量或产量的生物学和生态学效应以及作物对昆虫授粉的需求。昆虫对作物的授粉服务价值评估有助于掌握昆虫授粉为人类所带来的经济效应或经济价值,并帮助决策维持或增强授粉昆虫多样性和种群数量的人力、物力和财力投入。  相似文献   

4.
Pollinators are beneficial for many wild and crop plants. As a mass-flowering crop, oilseed rape has received much focus in terms of its pollination requirements but despite a threefold increase in area of cultivation of this crop in Ireland over the past 5 years, little is known about its pollination here. We surveyed the flower visiting insects found in commercial winter oilseed rape fields and evaluated the importance of different pollinator groups, investigated the contribution of insect pollination to oilseed rape seed production, and estimated the economic value of insect pollination to the crop at a national level. Our data showed that winter oilseed rape is visited by a wide variety of insect species, including the honeybee, bumblebees, solitary bees, and hoverflies. The honeybee, Eristalis hoverflies and bumblebees (especially Bombus sensu stricto and B. lapidarius) were the best pollinators of winter oilseed rape based on the number of pollen grains they carry, visitation rates per flower and their relative abundance per field. Exclusion of pollinators resulted in a 27 % decrease in the number of seeds produced, and a 30 % decrease in seed weight per pod in winter crops, with comparable values from a spring oilseed rape field also. The economic value of insect pollination to winter oilseed rape was estimated as €2.6 million per annum, while the contribution to spring oilseed rape was €1.3 million, resulting in an overall value of €3.9 million per annum. We can suggest the appropriate conservation and management of both honeybees and wild pollinators in agricultural areas to ensure continued provision of pollination services to oilseed rape, as a decrease in insect numbers has the potential to negatively influence crop yields.  相似文献   

5.
In many previous studies hawkmoths have been found to be involved in nocturnal pollination of many plants. But their role in crop pollination is still unexplored. This study tried to evaluate their potential to carry pollens of crop. Hawkmoths were collected by light traps and slides were made from the pollen attached to their body. The hawkmoths and the pollens were identified. A pollen transport network was created using the data. The species level indices of each plant species in the network were estimated. Only a small fraction of pollens were made by the crops among the total types of pollens carried by the hawkmoths. Rest of the pollens belonged to that of the non crops. The species level indices suggest the crop pollens to be relatively less important in the network as reflected in the lower values of species degree and species strength. The higher species level specialisation values of crop pollens suggested they are restricted to be carried by few hawkmoth species only. It is clearly revealed that hawkmoths carry mostly non crop pollens, not crop pollens.  相似文献   

6.
Brassica oilseed species now hold the third position among oilseed crops and are an important source of vegetable oil. The most common Brassica oil-seed crops grown for commercial purposes are rape seeds, (Brassica campestris L. and B. napus L.) and mustards (B. juncea (L.) Czern. & Coss. and B. carinata A.Br.). The other Brassica species such as B. nigra (L.) Koch and B. tournefortii Gouan are grown on a very small scale. Brassica napus, B. juncea, and B. carinata are amphidiploids, whereas B. campestris and B. nigra are diploid. Most of the Brassica species have been categorized as moderately salt tolerant, with the amphidiploid species being the relatively salt tolerant in comparison with the diploid species. Due to the higher salt tolerance of the amphidiploids, it has been suggested that their salt tolerance has been acquired from the A (B. campestris) and C (B. oleracea L.) genomes. However, significant inter- and intraspecific variation for salt tolerance exists within brassicas, which can be exploited through selection and breeding for enhancing salt tolerance of the crops. There are contrasting reports regarding the response of these species to salinity at different plant developmental stages, but in most of them it is evident that they maintain their degree of salt tolerance consistently throughout the plant ontogeny. The pattern of uptake and accumulation of toxic ions (Na+ and Cl?), in tissues of plants subjected to saline conditions appears to be mostly due to mechanism of partial ion exclusion (exclusion of Na+ and/or Cl?) in most of the species, although ion inclusion in some cases at intraspecific levels has also been observed. Maintenance of high tissue K+/Na+ and Ca2 +/Na+ ratios has been suggested as an important selection criterion for salt-tolerance in brassicas. Osmotic adjustment has also been reported in Brassica plants subjected to saline conditions, but particularly to a large extent in salt-tolerant species or cultivars. The roles of important organic osmotica such as total soluble sugars, free amino acids, and free proline, which are central to osmotic adjustment, have been discussed. In canola, B. napus, no positive relationship has been observed between salt tolerance and erucic acid content of seed oil in different cultivars. Furthermore, glucosinolate content of the seed meal in canola generally increases with an increase in salt level of the growth medium. This review highlights the responses of potential Brassica crops to soil salinity from the whole plant to the molecular level. It also describes the efforts made during the past millennium in uncovering the mechanism(s) of salinity tolerance of these crops both at the whole plant and cellular levels. The important selection criteria, which are used by researchers to enhance the degree of salinity tolerance in brassicas, are summarized. In addition, the vital role of genetic engineering and molecular biology approaches to the improvement of salt tolerance in brassicas is emphasized.  相似文献   

7.
Pollination is a crucial plant–animal interaction in ecosystems, and moths (Lepidoptera) are a widespread and species-rich group of flower visitors. In this article, plant and moth species connected via pollination interactions were identified from the literature, and information on the relevance of moth pollination in various ecosystems, including agro-ecosystems, was compiled, particularly for Europe and North America. Overall, 227 moth–flower pollination interactions were found, including certain specialized relationships between plants and pollinating seed predators. Most of the interactions could be attributed to the moth families Noctuidae (90 interactions, 56 species) and Sphingidae (85 interactions, 32 species), and to the plant families Orchidaceae (109 interactions, 22 species) and Caryophyllaceae (59 interactions, 16 species). Limited information is available on the role of moth pollination in natural ecosystems (7 studies). In temperate agro-ecosystems, moths are most likely not essential to crop pollination, but they can contribute to the pollination of non-crop plants, which are crucial to maintaining biodiversity in these ecosystems. In general, the role of moths as pollinators appears to be underestimated because only a few studies on moth pollination are available, and long-term, ecosystem-scale research is necessary to address temporal fluctuations in their abundance and community composition.  相似文献   

8.
Specifying the relationship between pests and their host plants in terms of damage is one of the basic concepts of integrated pest management (IPM) programmes. The crop loss and economic injury level (EIL) of Tuta absoluta (Lepidoptera: Gelechiidae) were determined on different tomato cultivars using gain threshold (field experiment) and regression (semi‐field experiment) methods. By assessing the crop loss in 2015 and 2016, four out of seven infested tomato cultivars had a significant yield loss in terms of weight of total fruits versus the control under the open‐field conditions. However, the total number of tomato cultivars had no significant difference to control treatment. The semi‐field experiment included six treatments (0, 2, 4, 6, 8 and 10 gravid females/plant) and examined two tomato cultivars. The tomato cages with between 6 and 10 gravid females/plant showed the highest number and weight of damaged fruits. Based on pesticide control costs, the market value of tomato and the control efficacy, we determined the EIL for T. absoluta. In the field experiment, the EIL value for T. absoluta on “Petomech,” “Cal JN3,” “Rio Grande” and “Early Urbana Y” cultivars was 4.15, 4.47, 4.70 and 5.04 larvae per plant, respectively. Based on regression equations, we calculated the EIL values for T. absoluta on “Cal JN3” and “Early Urbana Y” to be 4.75 and 5.44 larvae/plant, respectively. Crop loss assessment and EIL are necessary components of cost‐effective IPM programs and can be effective tools for making decisions about the application of pesticides against T. absoluta.  相似文献   

9.
倒伏是植株与其生长的环境条件相互作用的结果,是禾谷类作物产量和品种的重要限制因素。诱发倒伏的自然条件不是年年发生,但发生的程度差异很大,难以在自然条件下重复评价作物的倒伏性,因而人工诱发倒伏对于作物抗倒性的评价十分重要。谷子是非常容易发生倒伏的禾谷类作物,抗倒性的强弱是决定谷子高产、稳产的关键因素之一。由于谷子抗倒性的研究相对较少,本文通过对禾谷类作物抗倒伏性研究方法和评价指标的述评,为谷子抗倒性的研究提供借鉴,并对谷子倒伏与植株和产量性状的关系、品种抗倒性评价的指标等相关研究的进展做一综述。  相似文献   

10.
Pollination limitation and its impact on agricultural production is a serious concern of recent time. Assessment of the extent of dependency of various pollinator dependent crops on insect pollination assumes importance in this context. On the other hand, measures for restoring the pollination service needs to be explored for sustainable production of economically important crops particularly for the benefit of the small and marginal farmers. The present study aimed to assess the extent of insect pollinator dependency of brinjal (eggplant) fruit production and impact of honey bee (Apis cerana F) box introduction on the production in vegetable farms of North 24 Parganas, West Bengal, India. Through a pollinator exclusion experiment using enclosures it was found that brinjal fruit production reduces by 54.5 % when they are pollinator limited. This finding is in contrast with earlier report of 25 % dependency. The flower density in a pollinator limited environment was observed to increase by 31 %. This might be plant’s response to pollinator limitation where the plant invests more on reproductive structure than vegetative structures. However, this requires further exploration. Introduction of bee boxes in brinjal, pumpkin and pointed gourd farms showed significant increase in fruit production. This indicates both pollination limitation as well as the need for increasing the pollinators in the crop field for sustainable crop production.  相似文献   

11.
The production of diverse and affordable agricultural crop species depends on pollination services provided by bees. Indeed, the proportion of pollinator‐dependent crops is increasing globally. Agriculture relies heavily on the domesticated honeybee; the services provided by this single species are under threat and becoming increasingly costly. Importantly, the free pollination services provided by diverse wild bee communities have been shown to be sufficient for high agricultural yields in some systems. However, stable, functional wild bee communities require floral resources, such as pollen and nectar, throughout their active season, not just when crop species are in flower. To target floral provisioning efforts to conserve and support native and managed bee species, we apply network theoretical methods incorporating plant and pollinator phenologies. Using a two‐year dataset comprising interactions between bees (superfamily Apoidea, Anthophila) and 25 native perennial plant species in floral provisioning habitat, we identify plant and bee species that provide a key and central role to the stability of the structure of this community. We also examine three specific case studies: how provisioning habitat can provide temporally continuous support for honeybees (Apis mellifera) and bumblebees (Bombus impatiens), and how resource supplementation strategies might be designed for a single genus of important orchard pollinators (Osmia). This framework could be used to provide native bee communities with additional, well‐targeted floral resources to ensure that they not only survive, but also thrive.  相似文献   

12.
木蜂作为蜜蜂科的重要类群,是热带和亚热带地区显花植物常见的传粉者.木蜂具有访花的季节时间长、访花植物种类多、能耐高温或低光照、能嗡声传粉等特点.这些访花特点是木蜂作为热带植物、尤其是温室作物、夜间开花植物和部分茄属植物的重要传粉者.近年来国外已经证明木蜂能有效为蓝莓、西番莲、荷包豆、温室西红柿和温室甜瓜授粉,但我国有关木蜂为多数农作物传粉的重要性和有效性的证据较少.本文综述了近年来木蜂的访花行为和传粉作用的研究进展,为进一步保护、管理和利用木蜂资源提供理论依据.  相似文献   

13.
The olive originated in the Mediterranean region, and is most extensively cultivated oleiferous tree species in the world due to its high economic value. The olive has been introduced to China for more than 50 years, and some cultivars have showed good ecological suitability. The plantation of olive in China is increasing rapidly. However, many olive trees during the fruiting age showed the low fruit-setting rates and unstable fruit yields. Studies on pollination biology of olive are important to improve olive fruit-setting rates, genetic resources, and clonal selection and cross-breeding. Overseas much have been done about studies on pollination biology of olive, which are still scarce in China. In this paper, we presented a review of the recent advances in the pollination biology of olive, with the emphasis on blossom phenological characteristics, floral morphology, pollen germination, mating system, as well as their impacts on the fruit set of olive. The future researches in China were subsequently suggested as follows: (1) Strengthen the basic researches of olive pollination biology, including the ratio between monoecious and andromonoecious flowers in main introduced cultivars, the mechanisms for the maintenance of the olive sexual system, and the functional differences between monoecious and andromonoecious flowers and their relationship with wind-pollination, (2) Both field artificial pollination and molecular technology should be combined to elucidate the olive breeding system of cultivars, to explore the genetic and physiological mechanisms of self-infertility and cross-pollination, and to find the determinative factors of affecting the pollination compatibility of various cultivars, and (3) Studies on both olive pollination biology and breeding system should be combined to analyze comprehensively the effects of pollination and fertilization processes on fruit setting and early fruit development.  相似文献   

14.
Studies were conducted on eight sugarcane (Saccharum spp. hydrid) cultivars during the 1982–83 (plant crop) and 1983–84 (ratoon crop) growing seasons to determine the effects of glyphosine (Polaris) (N,N-bis (phosphonomethyl) glycine) and glyphosate (Polado) (sodium-N-(phosphonomethyl) glycine) on stalk sucrose content and yield. Difference due to crops (plant vs. ratoon) for sugarcane quality, kilograms of sugar per ton of cane (S/T), sugarcane yield, tons of cane per hectare (TCH), and sugar yield, tons of sugar per hectare (TSH) were significant. Significant differences were found in quality for the ratoon crop and cane and sugar yield in both crops due to ripener treatment. Cultivars in both crops differed significantly in quality and yield. Harvest dates were significantly different for all plant characteristics. Interactions of cultivar by treatment for the plant crop, harvest date by treatment for the ratoon crop, and cultivar by harvest date for both crops for cane quality also were significant. Time from ripener application to achievement of maximum sugar concentration also depended on cultivar. This is important in determining the economic benefits of a ripener treatment. Climatic conditions may also affect the benefits of such applications.  相似文献   

15.
《Journal of Asia》2022,25(1):101844
Brassica rapa L., is a crop grown globally and studies have indicated that insect pollination can improve yields. However, the importance of insect pollination in this crop depends on cultivar reproductive biology, insect pollinator species and their abundances. In Bangladesh, the acreage of B. rapa for oilseed production has been expanding, but little is known about whether insects contribute to yield improvements. Using the commonly grown variety Tori-7, we found that plants with inflorescences left exposed to flower visiting insects (body width > 1.5 mm) had a 30.8% greater seed yield compared to those where insect flower visitors were excluded. Of 794 insect flower visiting individuals recorded from observation and trapping surveys conducted across four separate fields, Apis bees (four spp.) were the most abundant (66.1%), followed by flies Musca domestica (14.7%), Sepsis fulgens (6.3%) and hoverflies (3.0%; 3 spp; Syrphidae). Other flower visitors included ants, wasps, beetles, butterflies and moths. For the cultivar assessed, we calculated the economic value of oilseed rape was $US 87.5 million per annum in Bangladesh, of which the economic value of insect pollination was $US 26.92 million per annum. Thus, one in every four dollars earned by our Bangladeshi growers resulted from insect crop pollination. This demonstrates to growers the need to promote and protect insect pollination to optimize their economic returns.  相似文献   

16.
Masting, the intermittent and synchronized production of seeds, is a common and important phenomenon throughout the plant kingdom. Surprisingly, the proximate mechanisms by which populations of masting plants synchronize their seed sets have been relatively unexplored. We examined how temperature influences the acorn crop of the valley oak Quercus lobata, a masting species common in California, USA, over 33 years in order to assess whether temperature acts directly on acorn crop as a cue or whether it acts instead through intermediate steps indicative of a direct mechanistic connection to acorn production. Compared to several alternatives, the difference in temperature during the spring flowering period over the prior two years (Δt) was a good predictor of annual acorn crop in valley oak, as proposed recently by Kelly et al. Significantly, Δt correlates positively with temperatures the previous April, a likely driver of pollination success in valley oak, and negatively with the previous year's acorn crop, which is in turn negatively correlated with the current year's acorn crop, presumably due to resource limitation. Thus, the success of Δt is not as a cue but rather explained by its close relationship to the proximate drivers that have a direct, mechanistic relationship with acorn crop size.  相似文献   

17.
This review focuses on feedback pathways that serve to match plant energy acquisition with plant energy utilization, and thereby aid in the optimization of chloroplast and whole-plant function in a given environment. First, the role of source–sink signalling in adjusting photosynthetic capacity (light harvesting, photochemistry and carbon fixation) to meet whole-plant carbohydrate demand is briefly reviewed. Contrasting overall outcomes, i.e. increased plant growth versus plant growth arrest, are described and related to respective contrasting environments that either do or do not present opportunities for plant growth. Next, new insights into chloroplast-generated oxidative signals, and their modulation by specific components of the chloroplast''s photoprotective network, are reviewed with respect to their ability to block foliar phloem-loading complexes, and, thereby, affect both plant growth and plant biotic defences. Lastly, carbon export capacity is described as a newly identified tuning point that has been subjected to the evolution of differential responses in plant varieties (ecotypes) and species from different geographical origins with contrasting environmental challenges.  相似文献   

18.
Sugarcane is a multipurpose crop whose components may be used, in addition to sugar production, for various energy carriers or end‐products (electricity, liquid biofuels and heat) which enhance its economic potential. For many years, plant breeders and agronomists have focused on increasing sucrose yields per hectare and millers on increasing recoverable sucrose per ton of sugarcane in sugar mills. Attempting to exploit the energy potential of sugarcane more fully, calls for a more holistic approach focusing on both sucrose and lignocellulosic components of sugarcane biomass, and gaining some insight into the management practices required to optimize sugarcane cropping systems in these respects. Such options include genotype selection, harvest date with respect to the crop's growing cycle, crop type (plant crop vs. ratoon crops) and harvesting systems (mechanical vs. manual). The effects of these factors are strongly modulated by climate and soil properties, and these interactions are overall poorly known. Here, we set out to examine sugarcane infield management × environmental interactions with respect to (i) sugarcane yield and partitioning of the aboveground biomass; and (ii) sugarcane milling products (recoverable sucrose yield and amounts of coproducts) and their derived energy carriers. Three Saccharum cv. cultivars (R570, R579 and R585) were planted in three locations on La Reunion Island with contrasting management practices and climatological conditions. Quality characteristics of the samples were assessed by conventional and near infrared spectroscopy methods. Product, coproducts and potential energy production were measured and computed using transfer equations and a mill‐operating model. Yields and quality characteristics from cultivars and harvesting systems were affected differently by environmental factors – low temperature and radiation, and water stress. The current study also provides valuable information on how combinations between environments, genotypes and practices affect yield and partitioning of the aboveground biomass, and food and energy production.  相似文献   

19.
The paper deals with the problem of designing a teacher's guide which will encourage and assist a teacher to arrive at well-reasoned independent decisions, and respect the teacher's experience and intellectual autonomy. The method described pertains to independently developed materials, not developed for any particular curriculum or teaching approach, thus leaving decisions about their adoption and adaptation to the teacher. A representative sample of teachers was used to obtain feedback information before, during, and after teaching a newly developed laboratory block in genetics for the 11th–12th grade level (17–18 year olds). Questionnaire and interview methods were used. Twelve categories for possible inclusion in the teacher's guide emerged. Decisions on whether to include a category in the teacher's guide were shown to be based on the teachers' manifest degree of familiarity with it, their measure of (or lack of) awareness of its educational potential, and their expressed desires for assistance.  相似文献   

20.
Genetic improvement of crops has traditionally been achieved through sexual hybridization between related species, which has resulted in numerous cultivars with high yields and superior agronomic performance. Conventional plant breeding, sometimes combined with classical cytogenetic techniques, continues to be the main method of cereal crop improvement. More recently, through the introduction of new tools of biotechnology, crossing barriers have been overcome, and genes from unrelated sources have become available to be introduced asexually into plants. Cereal crops were initially difficult to genetically engineer, mainly due to their recalcitrance to in vitro regeneration and their resistance to Agrobacterium infection. Systematic screening of cultivars and explant tissues for regeneration potential, development of various DNA delivery methods and optimization of gene expression cassettes have produced transformation protocols for the major cereals, although some elite cultivars still remain recalcitrant to transformation. Most of the transgenic cereals developed for commercial purpose exhibit herbicide and/or insect resistance; traits that are often controlled by a single gene. In recent years, more complex traits, such as dough functionality in wheat and nutritional quality of rice have been improved by the use of biotechnology. The current challenges for genetic engineering of plants will be to understand and control factors causing transgene silencing, instability and rearrangement, which are often seen in transgenic plants and highly undesirable in lines to be used for crop development. Further improvement of current cereal cultivars is expected to benefit greatly from information emerging from the areas of genomics, proteomics and bioinformatics.  相似文献   

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