Social science input into IPM

Abstract

Metsulfuron methyl (Ally‐Dupont), a sulphonylurea herbicide, was tested at rates of 0.5–2.0 g a.i./ha for the control of Striga hermonthica (Del.) Benth. in two cultivars of sorghum in pot experiments. There was good to excellent Striga control at 1.0–2.0 g a.i./ha applied either pre‐emergence or post‐emergence to CSH‐1 or N‐13 sorghum. The herbicide was unacceptably toxic to the Striga‐susceptible CSH‐1 cultivar when applied pre‐emergence, thus eroding any benefits of Striga control. In the Striga‐tolerant N‐13 cultivar there were considerable increases in the growth of infected plants. The herbicide was better tolerated from post‐emergence applications by both cultivars, and CSH‐1 plants recovered enough growth from Striga infection to produce grain yields at 1–5 and 2.0 g a.i./ha. Herbicide application at 4 weeks after planting sorghum was less damaging than at 2 weeks. Herbicide safening with 1,8‐naphthalic anhydride did not provide any additional benefits with post‐emergence application. The efficacy of the pre‐emergence herbicide was similar with surface or incorporated application.     

洞庭湖区H10亚型禽流感监测及其遗传进化分析

为了解洞庭湖区H10 亚型禽流感病毒的流行分布及遗传进化情况,为该地区H10 亚型禽流感的防控及该亚型病毒在禽流感病毒进化中所起的作用提供一些参考。在环洞庭湖地区活禽批发市场和水禽场上采集家禽和环境拭子,对其进行病原分离、鉴定和测序,应用Mega 5 软件包对病毒基因进行多序列比对和进化树的绘制与分析。结果显示：在活禽批发市场上总共分离到11 株H10 亚型禽流感病毒,分离的H10 亚型禽流感阳性样品全来源于鸭拭子;在1 个鸭场分离到2 株H10 亚型禽流感病毒;其中2株分离毒株序列分析显示其HA蛋白的裂解位点为PELMQGR/GLF,属于低致病性病毒,与以往在其他国家（蒙古、瑞典、荷兰、泰国、日本等）野鸟中分离的H10亚型病毒处于同一分支。     

Characterization of Puccinia graminis f. sp. tritici isolates derived from an unusual wheat stem rust outbreak in Germany in 2013

An unusual stem rust infestation occurred in German wheat fields in summer 2013. This study analysed 48 isolates derived from 17 Puccinia graminis f. sp. tritici (Pgt) samples and six races were identified: TKTTF, TKKTF, TKPTF, TKKTP, PKPTF and MMMTF. Infection type and genotypic data confirmed that none of these races belonged to the TTKS (Ug99) race group. German isolates of race TKTTF are phenotypically different to the ones responsible for the stem rust epidemic in Ethiopia in 2013–2014. Forty isolates were genotyped using a custom SNP array. Phylogenetic analysis showed that these 40 isolates represented two distinct lineages (clade IV and clade V). Thirty‐eight isolates clustered into clade IV, which previously was defined by Ethiopian isolates of race TKTTF. Race TKKTP is of special concern due to its combined virulence to stem rust resistance genes Sr24, SrTmp and Sr1RS^Amigo. The vulnerability to race TKKTP in US and international winter wheat was confirmed as 55% of North American and international cultivars and breeding lines resistant to race TTKSK (Ug99) became susceptible to TKKTP. Races identified in Germany in 2013 confirmed the presence of virulence to important resistance genes that are effective against race TTKSK. This information should be useful for breeders to select diverse and effective resistance genes in order to provide more durable stem rust resistance and reduce the use of fungicides.     

柑橘黄龙病疫情监测与防控技术研究

为了研究柑橘黄龙病传播介体种群消长规律和疫情动态,破解柑橘黄龙病防控问题,以主栽的早熟‘宫川’品种为重点在古城和大田柑橘园设立2个柑橘木虱监测点,采用定点定人定树定枝定时方法对柑橘木虱进行系统监测;以乡镇为单位每年在10-11月的果实显症期对全市柑橘园柑橘黄龙病进行全境式普查。结果表明,柑橘木虱季节性消长规律主要呈三峰型曲线变化,其峰期主要在6月下旬至7月下旬、8月中旬至9月中旬、10月上旬至11月上旬,其年度之间和果园之间总体趋势基本一致,但其峰值峰次差异却较大,主要受初见期、基数和气温等三要素影响所致,并建立柑橘木虱时序成若虫数量与其气温关系模型：D=0.018T+17.365（n=36,r=0.3563*）。针对柑橘木虱传播柑橘黄龙病的特征特性,摸索集成了“一挖两治”防控策略和“三防五关”防控技术。经过3年的全面应用,将柑橘黄龙病发病面积持续控制在5%以内,2008-2010年将加权平均株发病率分别控制在0.084%、0.077%、0.051%,基本达到了持续控制效果,保障了临海市柑橘产业持续健康发展。     

Fungi and oomycetes in open irrigation systems: knowledge gaps and biosecurity implications

Water used for the irrigation of plants has the potential to harbour and spread plant pathogens yet little research is conducted within this field. This review was undertaken to critically review current understanding of waterborne fungal and oomycete plant pathogens in open irrigation systems, particularly in the context of plant biosecurity. It was determined that very limited data exists on these plant pathogens, with the majority of previous studies only recording pathogen presence. There are significant gaps in current knowledge of pathogen survival and spread, and very limited information on their ability to cause disease when contaminated irrigation water is applied to crops. This review highlights the need for new research on the epidemiology and pathogenicity of putative plant pathogens isolated from water, in order to determine their risk to crops. The importance of regular monitoring of irrigation systems for the early detection of plant pathogens is also discussed.     

牛奶中汞的风险分析

随着工业的发展,空气、水和土壤中汞的含量大幅增加,加大了食品中汞污染的隐患。奶牛摄入、饮用高汞含量的饲料和水都会代谢到乳中。因此,消费者对牛奶中汞的危害要给予高度关注。作者就牛奶中汞的存在形式、来源、危害、监管等方面进行阐述,以期增加消费者对牛奶中汞的科学认识。     

Serological Surveillance of Influenza A Virus Infection in Swine Populations in Fujian Province,China: No Evidence of Naturally Occurring H5N1 Infection in Pigs

Several highly pathogenic H5N1 avian influenza viruses were isolated from swine populations in Fujian Province, China, since 2001. Because it is thought that H5N1 infection in pigs might result in virus adaptation to humans, we surveyed swine populations in Fujian Province in 2004 and 2007 for serological evidence of the infection. Twenty‐five pig farms covering all nine administrative districts of Fujian Province were sampled and a total of 1407 serum specimens were collected. The haemagglutination inhibition (HI) tests revealed no evidence of H5 infection and only a few cases of H9 infection. The negative results for H5 infection were further verified by micro‐neutralization tests. By contrast, H1 influenza virus infections were prevalent in swine in both surveys according to the results of enzyme‐linked immunosorbent assay (ELISA). The H3 infection rate was reduced dramatically in 2007 compared with 2004, when examined by HI and ELISA. In summary, the results imply that the swine populations in Fujian Province had not been affected greatly by the H5N1 avian influenza virus, given that there is no serological evidence that H5N1 influenza virus has infected the pig populations. The reported isolates represent only sporadic cases.     

基于ARM的蛋鸡养殖场网络视频监控系统设计

提出了一种基于嵌入式技术的蛋鸡养殖场网络视频监控系统设计方案。在嵌入式终端上搭建Linux操作系统环境,并行处理视频和图像:通过H.264编码对基于V4L采集的视频进行压缩,并通过RTP/RTCP和UDP协议将视频传输到监控平台上进行解码和显示;同时采用Ohta阈值对帧拼接的图像进行二值化,获取距离图像,以鸡蛋半径为阈值再次进行二值化并对鸡蛋计数,通过OSD技术将鸡蛋总数叠加到视频上。现场试验表明,监控平台上实时显示的视频清晰,鸡蛋计数平均准确率为96.07%。     

Effect of Incandescent Light on Collection of West Nile Virus Vectors Using CDC Miniature Light Traps in Northern Colorado

To evaluate whether the presence of clear incandescent light was attractive or refractive to host-seeking mosquitoes in northern Colorado, a Bayesian hierarchical model was created to measure differences in trap effectiveness based on presence or absence of phototactic cues. A total of eight CDC miniature light traps (with and without light) were set weekly across four locations in northern Colorado between Weeks 23 and 32 of year 2020. Culex mosquitoes (Diptera: Culicidae) accounted for 81% of all collections in this study with two vectors of West Nile virus being represented. The probability of catching both Culex tarsalis Coquillett and Culex pipiens Linnaeus was reduced when traps were equipped with light, but the difference was not statistically significant for Culex tarsalis. The clear reduction in the number of Culex pipiens caught when these traps were equipped with light indicates negative phototactic behavior and underestimation with current surveillance strategies. Removal of light from these traps may aid our understanding of these species’ distribution within the environment, improve collection efficiency, and help guide implementation of targeted control measures used in public health mosquito control.