基于神经结构搜索的多种植物叶片病害识别

为实现植物病害的自动准确识别,该研究提出一种基于神经结构搜索的植物叶片图像病害识别方法,该方法能够依据特定数据集自动学习到合适的深度神经网络结构。采用包含14种作物和26种病害共54 306张的公开PlantVillage植物病害图像作为试验数据,按照4∶1的比例随机划分,分别用于神经结构搜索和测试搜索到的最优网络结构的性能。同时,为探究神经结构搜索对数据平衡问题是否敏感及图像在缺乏颜色信息时对神经结构搜索的影响,对训练数据进行过采样和亚采样平衡处理及灰度变换。试验结果显示,该研究方法在训练样本数据不平衡和平衡时均可以搜索出合适的网络结构,模型识别准确率分别为98.96%和99.01%;当采用未进行平衡处理的灰度图像作为训练数据时,模型识别准确率有所下降,为95.40%。该方法能够实现植物病害的准确识别,为科学制定病害防治策略提供有效的技术手段。     

Who is sowing our seeds? A systematic review of the use of plant genetic resources in research

Collections of plant genetic resources managed by genebanks function to conserve the range of genetic diversity present in crop genepools. They can facilitate access to valuable allelic variation for both plant breeders and researchers who are able to request germplasm for use in crop improvement and both basic and applied scientific research. The direct impact of genebank collections is often unclear as downstream uses of germplasm samples may not be reported back to the genebank of origin. This study aims to systematically review scientific use of germplasm using the UK Vegetable Genebank (UKVGB) as a model. Between the years of 1980–2016, a total of 271 publications were identified as using UKVGB material. The frequency of publications and the international nature of use increased significantly over the time period studied. Accessions directly sourced from the UKVGB made up the majority of material used by researchers, but material from research-derived resources such as differential sets and core collections or diversity sets have also been used. Resistance to pests and diseases and genetic diversity were the main topics of study although germplasm was used to address a wide range of other research questions. Genebanks such as UKVGB provide an essential resource of allelic diversity in crop genepools which supports a diverse range of research projects. The utilisation of these plant genetic resources has increased over time, contributing to a substantial number of publications. Developments in sequencing technologies have no doubt played a part as larger numbers of accessions can be utilized in a single experiment, but the increase also no doubt reflects a greater interest in the use of allelic diversity to overcome challenges in crop improvement and research.     

基于交互式骨架模型的玉米根系三维可视化研究

植物根系可视化交互设计对于提高虚拟植物生长研究整体水平意义重大。该文提出一种植物根系逐部位交互式精确设计方法，并在玉米根系建模中予以应用。通过分析玉米根系结构特征并建立其拓扑结构，采用交互式骨架模型确定其整体结构，设计密度函数确定分支数量和分布，利用模板技术衍生相似部位，利用带参数随机L系统产生一级侧根及根毛，对玉米根系各组成部位逐个精确建模，然后拼接形成完整的玉米根系。本系统综合可视化设计多种方法，交互性、真实感都比较好，既可展现玉米根系各组成部分细微特征，又可表现玉米根系整体特征。本系统研究和设计方法具有一定通用性，对其它可用轴线表示其拓扑结构的相似植物可视化建模也有一定借鉴意义。     

Advancement of noble metallic nanoparticles in agriculture: A promising future

Since the last decades, nanotechnology has gained the attention of researchers in the field of plant sciences. The characteristics of nanoparticles are reliant on their shape and size. Formulations involving noble metallic nanoparticles(NMNPs) offer novel technologies to boost agricultural productivity and minimize conventional pesticide use. The application of nanoparticles as nanofertilizer improves plant growth and enhances nutrient uptake efficiency. Noble metallic nanoparticles act as antim...     

逆境下植物电信号研究现状与发展趋势

植物电信号是参与植物体内生理调控和传送信息的重要生理信号,其变化是植物对外界环境刺激的快速响应,而逆境刺激一旦超出植物承受范围,便无法通过自身修复。因此,通过对逆境下植物电信号变化进行深入研究,可依据不同环境胁迫和激励植物电信号的综合分析建立相关模型,以探究植物的最适生长环境特征。本文基于目前的相关研究文献资料,对植物电信号及其对逆境反馈的研究现状进行了梳理归纳,并在现有技术基础上对其发展趋势进行展望,以期为科研人员深入研究植物电信号提供参考,进而为推动植物育种和高产优质种植业高质量发展提供科学依据。     

观赏植物病害数据库查询系统研建

利用ASP.NET技术建立了一个在Internet中实现查询观赏植物病害的数据库检索系统,并对其系统结构和功能设计进行了阐述。该系统可用于网上查询各种观赏植物病害的名称、病害发生症状、病原特征、病害发生规律、防治方法等信息。     

Identification of genetically modified potato (Solanum tuberosum) cultivars using event specific polymerase chain reaction

Several genetically modified (GM) cultivars are registered in Canada although they are not currently in commercial production. The GM cultivars can be distinguished from the non-GM and other GM cultivars by analyzing the DNA nucleotide sequence at the insertion site of the transgene corresponding to a single transformation event in the plant genome. Techniques based on modified polymerase chain reaction (PCR) strategies were used to generate sequence information from the plant genome flanking the insertion site of transgenic DNA for specific GM potato events. The plant genome sequence adjacent to the transgenic insertion was used to design PCR primers, which could be used in combination with a primer annealing to one of the nearby inserted genetic elements to amplify an event specific DNA fragment. The event specific PCR fragments generated were sequenced to confirm the specificity of the method.     

Suppressiveness of 18 composts against 7 pathosystems: Variability in pathogen response

Compost is often reported as a substrate that is able to suppress soilborne plant pathogens, but suppression varies according to the type of compost and pathosystem. Reports often deal with a single pathogen while in reality crops are attacked by multiple plant pathogens. The goal of the present study was to evaluate the disease suppression ability of a wide range of composts for a range of plant pathogens. This study was conducted by a consortium of researchers from several European countries. Composts originated from different countries and source materials including green and yard waste, straw, bark, biowaste and municipal sewage. Suppressiveness of compost-amended (20% vol./vol.) peat-based potting soil was determined against Verticillium dahliae on eggplant, Rhizoctonia solani on cauliflower, Phytophthora nicotianae on tomato, Phytophthora cinnamomi on lupin and Cylindrocladium spathiphylli on Spathiphyllum sp., and of compost-amended loamy soil (20% vol./vol.) against R. solani on Pinus sylvestris and Fusarium oxysporum f. sp. lini on flax. From the 120 bioassays involving 18 composts and 7 pathosystems, significant disease suppression was found in 54% of the cases while only 3% of the cases showed significant disease enhancement. Pathogens were affected differently by the composts. In general, prediction of disease suppression was better when parameters derived from the compost mixes were used rather than those derived from the pure composts. Regression analyses of disease suppression of the individual pathogens with parameters of compost-amended peat-based mixes revealed the following groupings: (1) competition-sensitive: F. oxysporum and R. solani/cauliflower; (2) rhizosphere-affected: V. dahliae; (3) pH-related: P. nicotianae; and (4) specific/unknown: R. solani/pine, P. cinnamomi and C. spathiphylli. It was concluded that application of compost has in general a positive or no effect on disease suppression, and only rarely a disease stimulating effect.     

Accessing genetic resources: international law establishes multilateral system

The International Treaty on Plant Genetic Resources for Food and Agriculture is rapidly gathering sufficient ratifications to become international law. Once it enters into force, it will define the rules for access and benefit-sharing associated with most genetic resources of major food crops. This paper explains how the new Multilateral System established by the Treaty will work, and points out a number of ambiguities and problems in the text. Despite these shortcomings, the Treaty provides the international community of researchers, plant breeders, and farmers with an opportunity to foster cooperation and further the conservation and use of plant genetic resources.     

AutoCAD自动生成系统在园林设计植物配置中的应用

植物种植设计是园林规划设计的重要组成部分。利用AutoCAD软件进行植物种植设计时,苗木量统计表的绘制是一项较为繁琐的工作,而利用AutoCAD自动生成系统自动提取及生成相关数据则可大大降低此工作量,提高工作效率。然而,目前尚没有清晰可行的研究方法来阐述这一操作方法,作者针对这一问题,提出了一个在植物种植设计中,植物名称、数量、规格等自动生成表格的方法。该方法明晰易懂,具有较强的实用性和可操作性。     

计算机软件技术在植保软件开发中的应用

结合计算机软件技术的发展就如何进行植保应用软件的开发的一些技术性问题进行了探讨。提出了植保科技人员应以软件工程理论为指导,把握计算机应用的发展趋势,选择适合于植保专业技术人员使用的应用软件开发方法和工具,组织好软件开发人员,开发高水平、高质量的植保应用软件系统。该文还以黄淮海地区麦蚜预测预报系统(HH-AphidGIS)的研制开发为例,就上述原则中各个方面的具体应用进行了阐述     

香蕉条斑病毒PCR检测方法的正交优化

香蕉条斑病毒引起的香蕉条斑病,对香蕉生产的危害越来越严重,因此对该病毒的检测也变得很重要。而PCR法已广泛用于植物病毒的检测,所以控制PCR的反应条件对结果的准确性有很大影响。由于在检测过程中使用的是较为敏感的简并引物,因此对PCR反应条件的要求较高。本文采用L9（3……4）正交设计对PCR体系的反应条件进行了优化。最终获得最佳反应条件为Mg^2＋ 1.5mmol／L,dNTP 0.15mmol／L,Primer O.5μmol／L,TaqDNA聚合酶1.5U。通过最佳反应条件对采集回来的其他带BSV的植株叶片和吸芽的总DNA进行PCR扩增,其结果均表现为比较稳定。     

Fertilizers and soil-borne diseases

Abstract. Nutrient manipulation through fertilization or modification of the soil environment to influence nutrient availability is an important cultural control for plant disease and an integral component of production agriculture. Fertilization decreases soil-borne diseases by maximizing the inherent disease resistance of plants, by facilitating disease escape through increased nutrient availability or stimulated plant growth, and by altering the external environment to influence the survival, germination and penetration of pathogens. The flexibility in most disease-nutrient interactions permits a much broader utilization of this cultural control in decreasing disease severity than is presently practised. It is clear that the severity of most diseases can be decreased and the chemical, biological or genetic control of many plant pathogens enhanced by proper fertilization. Breeding nutrient-efficient or disease-tolerant crops and establishing cultivar requirements should further improve production efficiency.     

基于轻量级CNN的植物病害识别方法及移动端应用

为了实现在手机端植物病害叶片检测,对MobileNet和Inception V3 2种轻量级卷积神经网络进行迁移学习,得到2种作物病害分类模型,将2种分类模型分别移植到Android手机端,在识别精度、运算速度和网络尺寸之间进行平衡,选择最优模型。试验表明,MobileNet和InceptionV3在PlantVillage数据集(共38类26种病害)上平均识别率分别是95.02%和95.62%。在自建图像集葡萄病害叶片的识别中MobileNet和InceptionV3平均识别率分别是87.50%、88.06%,Inception V3的整体识别精度略高,但MobileNet在所有类别的识别上均衡性更好;在模型尺寸方面Inception V3的模型尺寸大小为87.5 MB,MobileNet的模型尺寸为17.1 MB,大约是后者5倍;2种模型移植到手机端时,MobileNet和Inception V3的APP所占内存分别是21.5和125 MB;在手机端单张图片的识别时间方面,Inception V3平均计算时间约是174 ms,MobileNet的平均计算时间约是134 ms,后者的平均计算时间比前者快40 ms;在手机端MobileNet相比于Inception V3占用内存更小,运算时间更快。说明MobileNet更适合在手机端进行植物病害识别应用。     

基于WebGIS的农作物病虫害预警系统

为适应农作物病虫资料信息化、网络化、规范化的要求，及各级植保技术人员日常工作的需要，应用开源免费的设计软件PHP＋Apache＋MapServer＋MySQL，构建一套基于WebGIS的病虫数据库及自动预警系统（WPDAWS）。该系统采用开放式的设计模式，为各级用户（省、市、县）提供一个强大的数据管理平台。通过树型动态菜单和在线数据表设计系统，用户可根据需要自行按规范化标准建立和管理自己的病虫数据库（表）；应用WebGIS，系统可对大尺度、宏观的虫情数据进行分析和判断；系统可对用户的田间原始数据进行自动处理，对各种病虫进行短期预警；系统集成了数理统计分析模块，协助用户建立中长期预测模型。系统操作简单方便，应用性强，适用面广，对于加强农作物病虫害信息网络化管理和宏观科学决策具很高的应用价值。     

Following the track of “Híbrido de Timor” origin by cytogenetic and flow cytometry approaches

The supposedly first plant of the coffee cultivar “Híbrido de Timor” (HT) was found in 1927, being denoted as HT CIFC 4106. According to different researchers, this plant originated from a natural interspecific hybridation between Coffea arabica (4x = 44) and Coffea canephora (2x = 22). From HT CIFC 4106, other HT accessions were obtained and employed to establish germplasm banks in some countries. As HT has been widely used in Coffea breeding programs, this study aimed to characterize different HT accessions with regard to ploidy, nuclear DNA content and base composition. Based on these data, the ploidy of HT CIFC 4106 was determined, suggesting that this accession is an allotriploid formed from reduced reproductive cell of C. canephora and of C. arabica. All HT CIFC 4106 plants exhibited the same 2C-value, AT% and chromosome number, showing that vegetative propagation has enabled the multiplication and germplasm conservation of this cytotype since 1927. Further five analyzed HT accessions showed distinct nuclear 2C-value and AT%. Since HT CIFC 4106 has been considered the first HT, it is suggested that aneuploid reproductive cells of this HT originated the other plants. Considering that HT accessions are used in the development of C. arabica cultivars, the findings of this study are important for the design of strategies to obtain new cultivars for breeding programs. Moreover, these data represent the first step to understand the origin and genome evolution of the HT.     

品种及种苗规格对当归成药期质量和经济效益的影响

当归是甘肃省定西市品牌大宗道地药材之一,但生产中的早薹问题导致其成药期质量下降,已成为制约当地当归产业发展的最大瓶颈。为了筛选出适宜在当地种植的最佳当归品种和种苗,以岷归系列品种为试材,采用二因素随机区组设计,研究了不同当归品种及其种苗规格对成药期当归质量和经济收益的影响。结果表明,选择移栽单株鲜重约0.7 g、主根长7.1 cm、侧根数少于0.2条/株的岷归4号种苗,是最适宜获得当归主要农艺性状较优、早薹率低、抗病性较强、产量及经济收益高的种植方案。应用该种苗种植时,当归单株鲜根重最重,为69.3 g;鲜根折合产量最高,为11 800.0 kg/hm2;经济纯收益最高,为67 600.0元/hm2;产投比最优,为21.1元/元。建议在定西地区及类似区立地条件下,优先选择岷归4号小种苗。     

Guidelines for measuring and reporting environmental factors in controlled environment facilities

Abstract

Guidelines for measuring and reporting environmental factors in growth chamber and other controlled environment studies of plant growth are listed. These guidelines were developed by researchers on the North Central Regional Committee NCR‐101 on Growth Chamber Use concerned with the use of controlled environment facilities for plant research. Adoption of these standardized guidelines should improve the quality of plant research in such facilities.     

热红外成像用于番茄花叶病早期检测的研究

由于蒸腾作用与植物叶片温度成负相关;利用热红外成像技术研究感染番茄花叶病的番茄叶片表面温度的变化与叶片病变程度的关系,可为实现番茄花叶病早期检测提供依据。以感染番茄花叶病的番茄叶片为材料,在温室条件下,利用热红外成像仪连续检测受病害侵染的番茄叶片表面的温度变化,发现在叶片的病变部位高于正常叶片0.5～1.2℃,且在肉眼无法观测到病变时,从热红外图像已经能发现感染叶片与正常叶片间明显的温度差异。因此,在温室条件下,感染番茄花叶病的叶片表面温差可以显著反应番茄叶片染病程度,叶面温差可以作为鉴别叶片是否感染番茄花叶病的一个指标,将热红外成像技术运用于番茄花叶病早期检测是可行的。     

Combination of agricultural waste compost and biofertilizer improves yield and enhances the sustainability of a pepper field

Application of plant growth‐promoting rhizobacteria (PGPR) has been considered as an environmentally friendly method for crop yield promotion as well as plant disease management. Efforts have been devoted to unraveling mechanisms involved in bacteria–plant and bacteria–pathogen interactions. However, little is known on the effect of the interaction among PGPR, soil, and plant. We compared growth and yield promotion capacity of biofertilizer Ning Shield, a consortium of bacterial preparation used as a biofertilizer (BF), and its mixture with compost of agricultural waste including spent substrate of Pleurotus ostreatus (SSP)/Volvariella volvacea (SSV), chicken manure (CM), and inorganic fertilizer (IOF) in a pepper field, respectively. The disease control efficacy, pepper fruit preservation time, and nutrients were also determined. Soil nutrient parameters including organic matter and available NPK of treatments were assayed before and after one growth season. All of the mixture of BF+organic compost treatment significantly enhanced the yield and quality of pepper fruit. Moreover, disease control capacity was promoted by the mixture of BF+organic compost, with BF+SSV reaching the highest control efficacy of 81% on 60th day after transplanting, and remaining 76% at the 105^th day. The BF+SSV treatment showed soil fertility retention ability with higher soil nutrient contents after one growth season of pepper. This study provides evidence that, when combined with organic fertilizers such as spent mushroom substrate compost, beneficial microbes have the ability to promote plant growth and yield as well as suppress plant disease by sustaining soil fertility through complex bacteria–soil–plant interaction.