诱集植物在农业中的应用研究进展与展望

全世界每年因病虫害导致严重的农业经济损失, 为了减少病虫害的发生, 实际生产中通常使用大量化学农药, 然而农药的大量施用, 不仅造成环境污染和农产品安全问题, 还会使病虫害产生抗药性, 天敌种群受损, 从而导致病虫害爆发日益严重。种植诱集植物是一种环境友好型病虫害防控方法, 该方法主要是通过诱集植物吸引虫害和降低病害, 从而减少病虫害对主栽作物的危害, 达到保护主栽作物的目的, 最终减少农业上化学农药的使用。根据诱集植物自身特性, 将其分为五种主导作用类型: 传统诱集植物、致死型诱集植物、基因工程型诱集植物、生物辅助控制型诱集植物、化学信息素辅助作用型诱集植物等, 根据种植和利用方式, 将其分为: 围种诱集、间种诱集、连作诱集、与其它方式结合等。尽管关于诱集植物的研究已有近160年历史, 但有关高效诱集植物的筛选、诱集植物与主栽作物的优化配置模式与配套种植技术、诱集植物对靶标病虫害的作用机理、诱集植物在农业生产中的生态风险评估等仍不清楚, 且诱集植物仍具有较大开发潜力和应用价值, 如(1)开发应用诱集植物的环境污染修复功能及相关技术; (2)开发应用诱集植物的景观生态与休闲旅游功能及相关技术; (3)开发利用诱集植物对土壤的养分转化与固持提升功能(如固氮、固碳、固土功能等)、生物质能源功能、节能减排功能及相关技术; (4)开发应用诱集植物及其废弃物的经济产品功能及其可持续生产技术。论文综述了近年来国内外有关诱集植物的相关研究与实践应用, 旨在为诱集植物在农业生产中进行病虫害防治研究和应用提供相关参考。     

生物育种产业化面临的机遇与政策保障

随着中国转基因玉米和大豆产业化试点的推进，间接食用转基因农产品在中国大范围产业化种植到了关键时刻。为有序推进生物育种产业化进程，本文在回顾全球和中国转基因作物产业化历史的基础上，着重分析了中国生物育种产业化遇到的两大机遇: 一是中国转基因农产品的持续进口和间接食用在下游加工业和群众中积累了一定的消费基础；二是过去这些年中国转基因技术的研发和技术储备已为转基因作物产业化做出了良好准备。最后，本文从充分利用现有群众消费基础、进一步释放技术储备潜力、更加严格地做好全流程监管等方面，提出有序推进生物育种产业化的政策建议。     

Genetically modified crops and small-scale farmers: main opportunities and challenges

Although some important features of genetically modified (GM) crops such as insect resistance, herbicide tolerance, and drought tolerance might seem to be beneficial for small-scale farmers, the adoption of GM technology by smallholders is still slight. Identifying pros and cons of using this technology is important to understand the impacts of GM crops on these farmers. This article reviews the main opportunities and challenges of GM crops for small-scale farmers in developing countries. The most significant advantages of GM crops include being independent to farm size, environment protection, improvement of occupational health issues, and the potential of bio-fortified crops to reduce malnutrition. Challenges faced by small-scale farmers for adoption of GM crops comprise availability and accessibility of GM crop seeds, seed dissemination and price, and the lack of adequate information. In addition, R&D and production costs in using GM crops make it difficult for these farmers to adopt the use of these crops. Moreover, intellectual property right regulations may deprive resource poor farmers from the advantages of GM technology. Finally, concerns on socio-economic and environment safety issues are also addressed in this paper.     

阿根廷转基因作物安全管理制度概况及进展

阿根廷是最早采用转基因技术的国家之一,目前已成为全球第三大转基因作物种植国。阿根廷是全球尤其是拉美国家在生物技术产品监管和审批方面的先驱,其在转基因作物监管问题方面的丰富经验以及联合国粮食及农业组织的认可使阿根廷成为全球转基因作物监管的领导者之一。介绍了阿根廷转基因作物研发和应用、转基因作物监管体系、新型育种技术监管体系、转基因作物进出口情况以及追溯体系,讨论了转基因技术的引进对阿根廷的影响,旨在全面了解阿根廷转基因作物及新型育种技术的监管体系,为我国转基因作物安全管理提供参考。     

A survey of black dot and other fungal tuber blemishing diseases in British potato crops at harvest

Black dot and other fungal blemishing diseases were assessed on tubers from crops in eastern England in 1987 and 1988, and in 1989 and 1990 from crops throughout Great Britain. Black dot was found on tubers in crops from all areas of the country, and was most common in those from eastern and southern England. The disease was scarce on most Scottish crops, but occasionally some were severely affected. In 1988 there was no consistent relationship between the amounts of disease on the seed and subsequent ware crop. On average, the disease was more prevalent in irrigated crops and where the interval between successive potato crops was short. In 1990 treating seed tubers with fungicide had no effect on subsequent levels of disease. Few crops were unaffected by silver scurf, and it was most common in crops from southern and eastern England. In the national survey common scab was the most prevalent disease, black scurf was less common and skin spot and powdery scab uncommon except in some Scottish crops.     

Coexistence, North American style: regulation and litigation

Globally, biotech crops have left a legacy of success and some notable failures due to regulatory and litigious barriers to entry, with a pipeline of potentially beneficial biotech agricultural products lined up and awaiting approval. Compared with traditional agriculture, these crops provide significant health benefits to environmental and human health benefits, including organic systems. While the rest of the world has increased acreage of biotech crops at a steady annual rate of 10%, North America-the birthplace of most biotech crops-has reached a critical turning point in its regulatory evolution. Biotech crops can play a major role in creating a more sustainable agricultural landscape, which is increasingly well-documented, but future commercial use may be hampered by regulation and litigation that place organic and non-GMO agriculture on a pedestal, which could force many biotech crops into containment. If producers of biotech crops are required to prevent their crops from contaminating these other, high premium specialty crops through migration, innovation in agricultural biotechnology will suffer (as the European experience with agricultural biotechnology clearly demonstrates).     

Diversity and phenology of weed communities in the Nile Delta region

This study evaluates the species diversity and phe-nological behaviour of the weed communities associated with the common crops in the Nile Delta region (three winter crops: Egyptian clover, broad beans and wheat; and three summer crops: cotton, maize and rice). The weed communities of winter crops are of higher diversity than those of summer crops, presumably due to differences in sowing and weeding processes. The phenological sequences of the weed communities are, in most cases, closely related to those of the crops in which they occur. The correspondence between the crucial periods in the life cycle of the weed and the crop (seedling establishment and fruiting) often leads to severe competition.     

Alfalfa mosaic and cucumber mosaic virus infection in chickpea and lentil: incidence and seed transmission

Samples collected in 1994 and 1995 from commercial crops of chickpeas and lentils growing in the agricultural region of south-west Western Australia were tested for infection with alfalfa mosaic (AMV) and cucumber mosaic (CMV) viruses, and for members of the family Potyviridae using enzyme-linked immunosorbent assay (ELISA). In 1994 no virus was detected in the 21 chickpea crops tested but in 1995, out of 42 crops, AMV was found in two and CMV in seven. With lentils, AMV and/or CMV was found in three out of 14 crops in 1994 and 4 out of 13 in 1995, both viruses being detected in two crops in each year. Similar tests on samples from chickpea and lentil crops and plots growing at experimental sites, revealed more frequent infection with both viruses. No potyvirus infection was found in chickpeas or lentils in agricultural areas either in commercial crops or at experimental sites. However, bean yellow mosaic virus (BYMV) was detected along with AMV and CMV in irrigated plots of chickpeas and lentils at a site in Perth. When samples of seed from infected crops or plots of chickpeas and lentils were germinated and leaves or roots of seedlings tested for virus infection by ELISA, AMV and CMV were found to be seed-borne in both while BYMV was seed-borne in lentils. The rates of transmission found through seed of chickpea to seedlings were 0.1–1% with AMV and 0.1–2% with CMV. Seed transmission rates with lentil were 0.1–5% for AMV, 0.1–1% for CMV and 0.8% for BYMV. Individual seed samples of lentil and chickpea sometimes contained both AMV and CMV. With both species, infection with AMV and CMV was sometimes found in commercial seed stocks or seed stocks from multiplication crops of advanced selections nearing release as new cultivars. Seed-borne virus infection has important practical implications, as virus sources can be re-introduced every year to chickpea and lentil crops or plots through sowing infected seed stocks leading to spread of infection by aphid vectors, losses in grain yield and further contamination of seed stocks.     

Transgenic,transplastomic and other genetically modified plants: a Canadian perspective

Since the mid 1990s, genetically modified (GM) crops have been grown commercially in Canada on a scale that has increased steadily over the years. An intense debate ensued, as elsewhere, and many fears were expressed regarding not only the technology itself but some of the main GM crops being grown. It would seem appropriate at this time to examine how these novel crops compare to crops bred by more traditional means and what impacts these GM crops have had based on experience and not merely on conjecture. To begin, we will put things in a historical perspective and recall how domestication and conventional plant breeding have shaped the crops of today. Then, we will describe briefly the distinctive features of GM plants (obtained so far mainly by nuclear transgenesis) and how these novel crops are regulated in Canada. We will then give two examples of widely grown GM crops in Canada (insect-resistant corn and herbicide-tolerant canola) and examine the main questions that were raised as well as the actual impacts these crops have had on the farm. These examples will help us outline some of the limitations of the current generation of GM plants and, finally, we will try to get a glimpse of the future by examining some recent technical developments in the field of recombinant DNA technologies applied to plant breeding.     

覆盖作物的种植现状及其对下茬作物生长和土壤环境影响的研究进展

覆盖作物指的是在农业生产间隙种植,使土壤在时间或空间上减少或避免裸露的一种作物。其能使农田土壤免受风蚀、水蚀和人为扰动的影响,被认为是一种新型的保护性耕作方式。本文简要介绍了农田覆盖作物的种植管理情况,包括种植品种、耕作模式和绿肥作物的灭生还田方式等,可为推广覆盖作物在农田休闲期的高效大面积种植提供参考。基于国内外研究综述了绿肥种植对经济作物、土壤质量、杂草抑制、温室气体排放和土壤微生物等的影响及研究进展,阐明了覆盖作物对农田生态系统的诸多益处。尽管覆盖作物存在局限性,例如短期收益不明显、管理措施不当会造成作物减产等,但其在改善土壤质量、实现农业可持续发展方面仍然具有重要的应用价值。     

Global climate niche estimates for bioenergy crops and invasive species of agronomic origin: potential problems and opportunities

The global push towards a more biomass-based energy sector is ramping up efforts to adopt regionally appropriate high-yielding crops. As potential bioenergy crops are being moved around the world an assessment of the climatic suitability would be a prudent first step in identifying suitable areas of productivity and risk. Additionally, this assessment also provides a necessary step in evaluating the invasive potential of bioenergy crops, which present a possible negative externality to the bioeconomy. Therefore, we provide the first global climate niche assessment for the major graminaceous (9), herbaceous (3), and woody (4) bioenergy crops. Additionally, we contrast these with climate niche assessments for North American invasive species that were originally introduced for agronomic purposes as examples of well-intentioned introductions gone awry. With few exceptions (e.g., Saccharum officinarum, Pennisetum purpureum), the bioenergy crops exhibit broad climatic tolerance, which allows tremendous flexibility in choosing crops, especially in areas with high summer rainfall and long growing seasons (e.g., southeastern US, Amazon Basin, eastern Australia). Unsurprisingly, the invasive species of agronomic origin have very similar global climate niche profiles as the proposed bioenergy crops, also demonstrating broad climatic tolerance. The ecoregional evaluation of bioenergy crops and known invasive species demonstrates tremendous overlap at both high (EI≥30) and moderate (EI≥20) climate suitability. The southern and western US ecoregions support the greatest number of invasive species of agronomic origin, especially the Southeastern USA Plains, Mixed Woods Plains, and Mediterranean California. Many regions of the world have a suitable climate for several bioenergy crops allowing selection of agro-ecoregionally appropriate crops. This model knowingly ignores the complex biotic interactions and edaphic conditions, but provides a robust assessment of the climate niche, which is valuable for agronomists, crop developers, and regulators seeking to choose agro-ecoregionally appropriate crops while minimizing the risk of invasive species.     

转基因作物在南非的应用及对我国的启示*

2019年是南非转基因作物商业化种植的第22年,3种主要转基因作物:棉花、玉米和大豆共种植了268万公顷,在全球所有转基因作物生产国中排名第八位,在非洲大陆排名第一位。这样一个具有超高转基因作物应用率的国家,有关其转基因商业化进程及现状鲜有系统介绍。综合1996~2019年的国际农业生物技术应用服务组织(International Service for the Acquisition of Agri-biotech Applications,ISAAA)的报告及其他数据资料,对南非转基因作物批准和种植情况、自主研发情况、安全管理制度、进出口情况及公众接受度做了概述,并以此为基础对我国转基因产业提出建议。     

Effect of annual and perennial cropping regimes in microplots on the population density and vertical distribution of Xiphinema diversicaudatum and on soil porosity

Long-term trends in populations of Xiphinema diversicaudatum were measured in two microplot experiments in which annual and perennial crops of seven plant families were grown in monoculture. Numbers of X. diversicaudatum increased under perennial ryegrass, raspberry and strawberry but decreased under hop, spring barley, potato, sugar beet, cabbage, winter wheat and winter beans; these effects probably reflected differences in the inherent host status of the crops. There were fewer X. diversicaudatum at 40–60 cm below annual crops than below perennial crops, and there were differences between perennial crops in nematode vertical distribution. Soil pore space did not limit nematode population density; total pore space was uniformly large under all crops and there was no detectable instability to water slaking. Under ryegrass a greater proportion of soil volume was occupied by pores too small to accommodate X. diversicaudatum, but since ryegrass supported the second largest nematode population, it seems unlikely that this was seriously limiting.     

Genomics and molecular breeding in lesser explored pulse crops: Current trends and future opportunities

Pulses are multipurpose crops for providing income, employment and food security in the underprivileged regions, notably the FAO-defined low-income food-deficit countries. Owing to their intrinsic ability to endure environmental adversities and the least input/management requirements, these crops remain central to subsistence farming. Given their pivotal role in rain-fed agriculture, substantial research has been invested to boost the productivity of these pulse crops. To this end, genomic tools and technologies have appeared as the compelling supplement to the conventional breeding. However, the progress in minor pulse crops including dry beans (Vigna spp.), lupins, lablab, lathyrus and vetches has remained unsatisfactory, hence these crops are often labeled as low profile or lesser researched. Nevertheless, recent scientific and technological breakthroughs particularly the next generation sequencing (NGS) are radically transforming the scenario of genomics and molecular breeding in these minor crops. NGS techniques have allowed de novo assembly of whole genomes in these orphan crops. Moreover, the availability of a reference genome sequence would promote re-sequencing of diverse genotypes to unlock allelic diversity at a genome-wide scale. In parallel, NGS has offered high-resolution genetic maps or more precisely, a robust genetic framework to implement whole-genome strategies for crop improvement. As has already been demonstrated in lupin, sequencing-based genotyping of the representative sample provided access to a number of functionally-relevant markers that could be deployed straight away in crop breeding programs. This article attempts to outline the recent progress made in genomics of these lesser explored pulse crops, and examines the prospects of genomics assisted integrated breeding to enhance and stabilize crop yields.     

转基因作物与非转基因作物的共存立法动态研究——以美、日、欧应对基因污染事件为视角

随着基因工程技术的运用与发展,越来越多的转基因作物基因污染事件的发生也引起了世界各国对转基因作物与非转基因作物之间的和谐发展问题的高度重视。以美、日、欧为代表,世界各国对转基因作物与非转基因作物的共存问题都进行了积极地探索。借鉴美、日、欧转基因与非转基因作物共存法律制度,以期为我国转基因与非转基因作物共存法律制度的构建提供参考。     

图位克隆技术在农作物基因分离中的应用与评价

图位克隆(Map-based cloning)作为分离基因的有效方法, 已在小基因组作物的基因分离中得到了广泛应用和发展, 而在具有大量重复DNA序列的大基因组作物中的应用仍存在挑战。基于图位克隆在基因分离中的重要性, 文章就图位克隆技术的基本内容及发展做简要概述, 着重对图位克隆技术在大基因组作物中的应用进行分析和评价, 同时对它今后可能的发展方向进行了讨论, 以期为大基因组作物基因的分离提供借鉴。     

A UK survey of the use and management of cover crops

There is a growing trend in the use of cover crops in the United Kingdom, and whilst research shows there are many soil and environmental benefits, little is known about the farmer's perspective of cover cropping. A survey was designed and distributed to ask farmers about their use and management of cover crops. The online survey received 117 usable responses between January and March 2017, following distribution through social media in the United Kingdom. The survey highlighted that 66% of respondents used cover crops following harvest in 2016. Respondents observed benefits to soil structure, soil erosion control and water infiltration in addition to reductions in the use of chemical fertilisers, herbicide and fuel use. Of those not using cover crops, 90% would consider their use in the future if additional information on their use and benefits were known in a UK context. Changes to the 2016 Basic Payment Scheme guidelines for cover crops would have been welcomed by 71% of respondents using cover crops.     

中国北方气候暖干化对粮食作物的影响及应对措施

东北、华北和西北50a来的平均气温增幅高于全国平均水平,气候变暖明显,尤其冬季增温最显著。区域增暖的极端最低气温远比极端最高气温的贡献大。东北、华北大部、西北东部降水量明显减少,平均每10a减少20—40mm,尤其春夏季减少最明显。这种趋势一直延续到20世纪90年代以后,干旱化趋势非常突出。在综述我国北方现代气候变化基本特征是暖干化的基础上,重点阐述了喜凉作物冬小麦、春小麦、马铃薯和喜温作物水稻、玉米、谷子、糜子等7种主要粮食作物的生长发育、品种熟性、种植区域与面积、产量与品质等对气候暖干化的响应特征。揭示了气候暖干化使春播作物播期提早,苗期生长发育速度加快,营养生长期提前,生殖生长期和全生育期延长;秋作物发育期推迟,生殖生长期和全生长期延长;越冬作物播期推迟,越冬死亡率降低,种植风险减少,春初提前返青,生殖生长期提早,全生育期缩短。使作物适宜种植区域向高纬度高海拔扩展;品种熟性向偏中晚熟高产品种发展;喜温作物和越冬作物以及冷凉气候区的作物种植面积迅速扩大;在旱作区种植不较耐旱的玉米、春小麦等作物种植面积受到制约。对雨养农业区的作物气候产量影响严重,尤其对不够耐旱的小麦和玉米的气候产量受影响最大;对较耐旱的谷子、糜子、马铃薯等影响较轻。从作物属性而言,对喜温作物水稻、玉米和越冬作物冬小麦有利于气候产量提高;对喜凉作物春小麦和马铃薯的气候产量将产生不利影响。同时,提出了从5个方面应对气候暖干化的技术措施,调整作物种植结构,确保粮食生产安全;根据不同气候年型调整各种作物种植比例;针对不同气候区域发展优势作物和配置作物种植格局;采取不同栽培技术和管理模式应对气候变化;采取综合配套技术提髙抵御灾害能力。为粮食作物安全生产和种植结构调整与布局提供科学依据。     

Domestication and crop evolution of wheat andbarley: Genes,genomics, and future directions

Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world's most important crops. Domestication of these crops from their wild ancestors required the evolution of traits useful to humans, rather than survival in their natural environment. Of these traits, grain retention and threshability, yield improvement, changes to photoperiod sensitivity and nutritional value are most pronounced between wild and domesticated forms. Knowledge about the geographical origins of these crops and the genes responsible for domestication traits largely pre-dates the era of nextgeneration sequencing, although sequencing will lead to new insights. Molecular markers were initially used to calculate distance(relatedness), genetic diversity and to generate genetic maps which were useful in cloning major domestication genes. Both crops are characterized by large,complex genomes which were long thought to be beyond the scope of whole-genome sequencing. However, advances in sequencing technologies have improved the state of genomic resources for both wheat and barley. The availability of reference genomes for wheat and some of its progenitors,as well as for barley, sets the stage for answering unresolved questions in domestication genomics of wheat and barley.     

Environmental fate and behaviour of antibiotic resistance genes and small interference RNAs released from genetically modified crops

Rising global populations have amplified food scarcity across the world and ushered in the development of genetically modified (GM) crops to overcome these challenges. Cultivation of major crops such as corn and soy has favoured GM crops over conventional varieties to meet crop production and resilience needs. Modern GM crops containing small interference RNA molecules and antibiotic resistance genes have become increasingly common in the United States. However, the use of these crops remains controversial due to the uncertainty regarding the unintended release of its genetic material into the environment and possible downstream effects on human and environmental health. DNA or RNA transgenes may be exuded from crop tissues during cultivation or released during plant decomposition and adsorbed by soil. This can contribute to the persistence and bioavailability in soil or water environment and possible uptake by soil microbial communities and further passing of this information to neighbouring bacteria, disrupting microbial ecosystem services such as nutrient cycling and soil fertility. In this review, transgene mechanisms of action, uses in crops, and knowledge regarding their environmental fate and impact to microbes are evaluated. This aims to encapsulate the current knowledge and promote further research regarding unintended effects transgenes may cause.