Epitrix flea beetles: new threats to potato production in Europe

Epitrix tuberis and E. cucumeris are major pests of potatoes in North America. E. tuberis causes the most serious damage because the larval feeding can cause superficial serpentine tunnelling on the surface of tubers as well as deeper pits. This damage can make crops unmarketable. By contrast, E. cucumeris mainly damages the foliage, and yield losses can occur when the adults reach high densities. In 2004, potato tuber damage characteristic of E. tuberis was seen in Portugal. In 2008, damage was more widespread and severe. E. cucumeris and a lesser known species, E. similaris, were recorded in affected fields. E. similaris has since been found across Galicia, Spain. E. similaris is thought to be the most likely cause of the tuber damage in Portugal, but it is possible that E. cucumeris or an as yet undetected Epitrix species is causing the damage. In 2010, a pest risk assessment for the Euro‐Mediterranean area identified the movement of adults and pupae with seed or ware potatoes and associated soil as being the highest‐risk pathways for the spread of Epitrix. In 2012, EU emergency measures were agreed to reduce the risk of further introductions and the rate of spread of these pests.     

Correction to: Biological,environmental and socioeconomic threats to citrus lime production

Journal of Plant Diseases and Protection - In the original publication, Narouei-Khandan et al.’s reference detail was incorrectly crosslinked with another article and missed to include in the...     

Cacao diseases: a global perspective from an industry point of view

ABSTRACT Diseases of cacao, Theobroma cacao, account for losses of more than 30% of the potential crop. These losses have caused a steady decline in production and a reduction in bean quality in almost all the cacao-producing areas in the world, especially in small-holder farms in Latin America and West Africa. The most significant diseases are witches' broom, caused by Moniliophthora perniciosa, which occurs mainly in South America; frosty pod rot, caused by M. roreri, which occurs mainly in Central and northern South America; and black pod disease, caused by several species of Phytophthora, which are distributed throughout the tropics. In view of the threat that these diseases pose to the sustainability of the cacao crop, Mars Inc. and their industry partners have funded collaborative research involving cacao research institutes and governmental and nongovernmental agencies. The objective of this global initiative is to develop short- to medium-term, low-cost, environmentally friendly disease-management strategies until disease tolerant varieties are widely available. These include good farming practices, biological control and the rational or minimal use of chemicals that could be used for integrated pest management (IPM). Farmer field schools are used to get these technologies to growers. This paper describes some of the key collaborative partners and projects that are underway in South America and West Africa.     

Biological,environmental and socioeconomic threats to citrus lime production

Journal of Plant Diseases and Protection - Limes as a fruit crop are of great economic importance, key to Asian and South American cuisines and cultivated in nearly all tropical and subtropical...     

两种值得关注的蓝莓病害

僵果病和炭疽病是蓝莓上普遍发生的两种重要真菌病害,危害极其严重,近年来随着蓝莓引种工作以及新鲜果实的大量进口,该病传入我国的风险逐渐增大。本文简要介绍了两种病害的病原、危害及分布、症状、病害循环、防治措施和检疫鉴定特征等,以其为防止这些病害随着引种工作传入我国提供参考。     

The increasing importance of herbicides in worldwide crop production

Herbicide use is increasingly being adopted around the world. Many developing countries (India, China, Bangladesh) are facing shortages of workers to hand weed fields as millions of people move from rural to urban areas. In these countries, herbicides are far cheaper and more readily available than labor for hand weeding. History shows that in industrializing countries in the past, including the United States, Germany, Japan and South Korea, the same phenomenon has occurred—as workers have left agriculture, herbicides have been adopted. It is inevitable that herbicide use will increase in sub‐Saharan Africa, not only because millions of people are leaving rural areas, creating shortages of hand weeders, but also because of the need to increase crop yields. Hand weeding has never been a very efficient method of weed control—often performed too late and not frequently enough. Uncontrolled weeds have been a major cause of low crop yields in sub‐Saharan Africa for a long time. In many parts of the world, herbicides are being increasingly used to replace tillage in order to improve environmental conditions. In comparison with tillage, herbicide use reduces erosion, fuel use, greenhouse gas emissions and nutrient run‐off and conserves water. © 2013 Society of Chemical Industry     

甘蔗重要病害分子检测技术

快速有效地对甘蔗重要病害病原进行诊断检测,明确监测病害的病原是科学有效防控甘蔗病害的基础和关键。云南省农业科学院甘蔗研究所通过探索研究、改进创新、优化建立了甘蔗黑穗病、锈病、白条病、宿根矮化病、赤条病、花叶病、斐济病、黄叶病、杆状病毒病和白叶病等10种重要病害13种病原的分子快速检测技术,为甘蔗病害的有效诊断和防控、脱毒健康种苗检测及引种检疫提供了技术支撑。     

Of mushrooms and chocolate trees: aetiology and phylogeny of witches' broom and frosty pod diseases of cacao

The troubled history of the two major diseases of the chocolate tree (Theobroma cacao) in South America, witches' broom and frosty pod, is reviewed, concentrating on critical aspects of the aetiology as well as the phylogeny of the causal agents. Both diseases are caused by sister species within the genus Moniliophthora, belonging to the Marasmiaceae family of mushrooms. The witches' broom pathogen, Moniliophthora perniciosa, evolved on the Amazonian side of the Andes and induces brooms not only in cacao and its relatives in the genera Theobroma and Herrania (Malvaceae), but also in species in the plant families Bignoniaceae, Malpighiaceae and Solanaceae, on which the mushrooms (basidiomata) are produced. Moniliophthora roreri, the type species of the genus, evolved as a pod pathogen on endemic Theobroma species on the western side of the northern Andean Cordillera. Because Moniliophthora was described originally as the asexual form of an unknown basidiomycete, the generic diagnosis is amended here to accommodate species with agaricoid basidiomata. In addition, the new variety M. roreri var. gileri is designated for the morphotype occurring on Theobroma gileri, in northwest Ecuador. Cytology studies indicate that the supposed conidia of M. roreri are, in fact, sexual spores (meiospores) and it is posited that the fruiting structure represents a much‐modified mushroom. Finally, based on preliminary data from pathogenicity testing, it is hypothesized that the true causal agent of both diseases is an as yet unidentified infectious agent vectored into the host by the fungus.     

西瓜重要种传病害研究进展

本文围绕目前我国西瓜生产中西瓜蔓枯病、细菌性果斑病、黄瓜绿斑驳病毒病等重要的种传病害,阐述了其发生与危害;讨论了国内外在病原物种子传带机制方面的研究进展;分析比较种子健康传统检测技术与现代分子检测技术的优点与局限性;总结现有的种子处理方法,最后提出了尚未明确和亟须研究的问题,为西瓜种传病害的防控提供参考。     

值得重视的两种柑橘真菌性病害

柑橘是我国第二大水果,是我国农业支柱产业之一。甜橙疮痂病(sweet orange scab)和壳针孢斑点病(septoria spot)是我国可能尚未发生,但面临较大入侵风险的两种柑橘真菌性病害。本文详细介绍了这两种病害的危害性、分布范围、症状、寄主范围、病原性质和发生规律,并分析了这些病害经繁殖材料和果品贸易入侵我国的风险,以期加深相关部门和从业人员对这两种病害的认识。     

Cacao resistance to Phytophthora: Effect of pathogen species, inoculation depths and pod maturity

Two species of Phytophthora (P. palmivora and P. capsici) and inoculations at two depths (3 mm and 9 mm) were tested each on 10 clones of Theobroma cacao to determine their effects on pod resistance. Ripe and unripe pods were also assessed to determine the influence of physiological status of the pod on the expression of resistance. The two pathogens tested (P. palmivora and P. capsici) differed significantly in their reactions on pods, with P. palmivora being more aggressive than P. capsici. However, the lack of interaction between clones and pathogen species and the similarity in the ranking of clones based on lesion size suggested that selection for resistant clones can be based on one of the two pathogens, preferably the more aggressive one. Pod reactions differed between inoculation depths (3 mm and 9 mm), and between pod maturity stages (ripe and unripe pods) with relatively larger lesions being recorded at 9 mm depth and on unripe pods as compared to those observed at 3 mm depth and on unripe pods, respectively. The magnitude of increase in lesion sizes, however, varied with genotypes, indicating that inoculation depth and pod maturity stage should be standardized in screening cacao germplasm for resistance to Phytophthora.     

Modelling land use strategies to optimise crop production and protection of ecologically important weed species

There is a need to develop farming systems that enable both a satisfactory level of crop production and suitable environmental conditions for natural species. Wildlife‐friendly cropping techniques, such as a reduced amount of applied herbicide or a lower crop density, might be adopted in order to maintain populations of weed species of biological interest. An alternative might be to adopt an intensive cropping system in a part of the field and spare the other part as set‐aside or field margins, available for the natural development of plant species. The objective of this study was to present a method to compare two strategies for maintaining a desirable level of abundance of a given species of interest in agricultural areas, specifically (i) a strategy based on a wildlife‐friendly cropping system in a large cultivated area and (ii) a strategy based on a more intensive cropping system in a reduced area of cultivation, i.e. with land‐sparing. The principle is to calculate the ratio of crop production obtained with strategy (i) to the production obtained with strategy (ii) for a given target density of natural species. We show that the value of this ratio, and thus the relative performance of the two strategies, depends on the density of the weed species that can be maintained in an uncultivated ecological area. The method is applied in case studies of two plant species with contrasting ecology and conservation goals. The numerical results show that the strategy based on a wildlife‐friendly cropping system is more profitable in most situations.     

甘肃省马铃薯主要病毒病发生情况调查

2015年-2016年,在甘肃省10个地市24个马铃薯主栽县(区)146个生态区域(乡镇)采集了757份具有典型症状的马铃薯样品,应用DAS-ELISA法进行检测,筛查6种主要病毒(PVX、PVY、PLRV、PVA、PVS和PVM)。结果表明:631份样品检测到病毒,PVS的检出率最高,达47.03%,PVY次之,为33.82%,PVA最低,只有0.63%;发生复合侵染的病毒主要为PVY+PVS,复合侵染率达到10.13%,三种病毒复合侵染主要是PVY+PVS+PVM;病毒种类和感病程度与品种、地域有关。     

Usefulness of the Detached Pod Test for Assessment of Cacao Resistance to Phytophthora Pod Rot

The detached pod test by spray method (DPT-SM) was developed to facilitate the screening of cacao genotypes for resistance to Phytophthora pod rot (PPR) caused by Phytophthora palmivora. The test has been adopted in many cacao research institutes, and it is imperative that its validity be assessed. In this study, 40 genotypes from various cacao groups were selected and screened for resistance to PPR by DPT-SM and field observations. Significant variation was observed in the reactions of the selected accessions based on the disease rating scale for DPT-SM and the percentage pod rot from field observations. A correlation coefficient of 0.68 (P<0.001) was observed between the results of year-1 and year-2 field observations. However, relatively lower correlation values were obtained between year-3 and year-1 (r=0.32; P=0.041) and year-3 and year-2 (r=0.35; P=0.025) field observations. A higher level of susceptibility was observed in the third year of field observations (63%) than in the first (15%) and second (25%) years. This suggests that the predisposing factors for PPR were unstable between the years of field observations. Data obtained from the Trinidad and Tobago Meteorological Services showed that the rainfall in November of the third year was higher than the amounts of rainfall in November of the first 2 years of field observations. This month marks the beginning of the main pod harvest season (November–February) and the high rainfall in November of the third year, and the presence of large number of mature pods may account in part for the increase in PPR in the third year of field observations than in the first 2 years. This shows that absolute reliance could not be placed on a single year of field observations in determining clonal resistance to PPR. A correlation coefficient of 0.59 (P<0.001) was obtained between the result of year-2 field observations and DPT-SM. Relatively lower correlation values were observed between DPT-SM and year-1 (r=0.55; P<0.001) and year-3 (r=0.44; P=0.005) field observations. The result of DPT-SM, however, shows a higher correlation (r=0.66; P<0.001) with the average of years 1–3 field observations. This suggests that a stronger association may exist between the result of DPT-SM and the cumulative data on field observations for a period longer than 3 years. The correlation (r=0.66; P<0.001) observed in this study confirms the usefulness of DPT-SM as an effective method of assessing clonal resistance to PPR and predicting field reaction in the long term. Since field observations are labour intensive and expensive to conduct on a yearly basis, the DPT-SM offers a cheaper and effective means of assessing clonal resistance to PPR. Being a non-destructive inoculation method, the DPT-SM provides a suitable option for cacao collections in genebanks to be assessed. It is also a cost-effective method for use in cacao breeding programmes. Based on its reliability, the DPT-SM has been adopted in the CFC/ICCO/IPGRI cocoa project ‘Cocoa Germplasm Utilization and Conservation: A Global Approach’ for the assessment of cacao resistance to PPR in several cocoa producing countries.     

近年我国重要苹果病害发生概况及研究进展

苹果是我国最重要的经济作物之一,截至2015年我国苹果种植面积达到232万hm~2,总产量超过4 200万t。各种病害仍是困扰我国苹果产业健康发展的限制性因素。腐烂病和枝干轮纹病依然是我国苹果最重要的枝干病害,斑点落叶病和白粉病连年发生,危害加重;霉心病在一些产区成为产业发展的限制性因素。病毒病病原种类还在增加,发生程度不断加重,已经上升为苹果主要病害。随着老果园重建的大范围开展,再植病害已经成为苹果产业可持续发展的障碍;缺素、裂果和冻害等非侵染性病害虽然不具传染性,但近年来发生面积不断扩大,对苹果产量的威胁在某些年份甚至较侵染性病害更为严重。本文系统总结了自2013年以来这些苹果主要病害的发生概况及研究进展,并分析了目前存在的问题,提出了相应的建议。     

Cacao leaf procyanidins increase locally and systemically in response to infection by Moniliophthora perniciosa basidiospores

Flavan-3-ol monomers and oligomers from dimers to decamers were quantitatively determined by HPLC-FLD in leaves of four Theobroma cacao varieties. Cacao flush leaves had higher procyanidin content than mature leaves. Moniliophthora perniciosa basidiospore infection results in an increase in cacao leaf procyanidins in the inoculated leaves, as well as in the uninoculated, adjacent, older leaves on an actively growing branch, resulting in both a local and systemic increase in procyanidin content in response to infection. Procyanidin oligomers increased significantly in leaves of the less susceptible genotype Scavina 6 upon infection, and total procyanidin levels were higher than in Cacao Comum a more disease susceptible genotype. Selection of genotypes with high constitutive and/or inducible content of procyanidins in young flush leaves may be a strategy to develop witches’ broom disease resistant cultivars.     

链格孢引起的病害严重危害农作物生产并危及农产品安全

链格孢属Alternaria Nees真菌是一类在自然环境中广泛分布的真菌,该属的一些种可引起多种重要农作物病害发生,严重危害农作物生产并造成巨大损失。另外,这些链格孢产生的毒素还积聚在农产品中,危及农产品食用安全。为此有必要加强有关链格孢病害的研究和治理。本文介绍了有关链格孢分类研究进展,近些年来链格孢危害农作物的主要种类及危害情况,以及世界范围内链格孢毒素所引发的农产品食用安全问题。在此基础上,也综述了链格孢病害的主要防控策略和治理技术。     

Rapid Screening of Cacao Genotypes for Field Resistance to Phytophthora palmivora Using Leaves, Twigs and Roots

Black pod, caused by Phytophthora spp. is one of the most important diseases of cacao occurring worldwide. Losses due to black pod caused by P. palmivora are still moderate in Côte d'Ivoire but P. megakarya causes high losses in Ghana and other Central African countries. Variation in field attack has been observed between cacao genotypes, but evaluation of pod losses is unsuitable for obtaining rapid progress in breeding. Results of inoculation tests using young detached leaves, twigs and roots, obtained from field and nursery plants, are presented here and compared to field resistance of similar genotypes observed over a 10-year period. Nine different Upper Amazon Forastero genotypes were tested together with progenies obtained by crossing these with the susceptible check IFC5 (Amelonado genotype). Rank correlations between the early screening tests and the level of field attack were positive and mostly significant (r=0.58–0.95). The coefficient of correlation was slightly higher for leaves (r=0.88) and roots (r=0.89) than for twigs (r=0.76). Also, resistance of the different plant organs was correlated (r=0.6–0.9). Resistance of the Upper Amazon parents was well correlated with the resistance of their cross progenies (r=0.7–0.9), suggesting that resistance is highly heritable. Resistance of leaves and twigs from the nursery was better correlated with field resistance than resistance of leaves and twigs from the field, which might result from more uniform growing conditions in the nursery. Inoculation of leaves appears the most suitable early screening method for black pod resistance. Application of this test in breeding more resistant cacao cultivars is discussed.     

安徽省主要农作物重大病虫未来发生趋势及其治理对策

安徽省地处温带和亚热带之间,气候过渡性明显。夏季气温较高,作物生长季较长,且降水偏多,但地域分布不均。全省南北区域跨度广,农业生态     

Transnational European research collaboration to tackle plant health threats: Euphresco and its contribution to the new EU Plant Health Regulation

The new EU Plant Health Regulation published in December 2016 is intended to modernize the EU plant health regime and to address the challenges posed by globalization of trade and climate change, overcoming the limits of the previous Directive. The main weaknesses of the approach taken so far are linked to the discontinuous links between phytosanitary policy (determined at EU level) and research supporting such a policy, implemented at country level. Since 2006 Euphresco has developed a platform for research coordination that supports capacity building and streamlines the delivery and use of research evidence to support plant health policy. The paper provides an opinion on how Euphresco (research) activities could support the implementation of the new EU Plant Health Regulation.