Control of Colorado beetle (Leptinotarsa decemlineata) in Poland1

Leptinotarsa decemlineata (Colorado beetle) was found in Poland for the first time in 1945 and a great invasion of this pest took place in 1950. It now plays a very important role in Polish plant protection, mainly because the acreage of potato in Poland amounts to about 1.8 million ha. The pest is controlled by repeated insecticide applications to a yearly total of 2 million ha, which is the highest amount of insecticides used in Poland. Research has been carried out in Poland on the following subjects: biology and ecology of Colorado beetle, influence of pest appearance and control on the biocenosis of fields, methods of control, biochemical factors influencing the life cycle, forecasts and warning of appearance, artificial diet, resistance of potato cultivars and reaction of leaf blades of potato to the eggs of Colorado beetle. Research is also carried out on chemical control, modernization of pesticide recommendations and resistance of Colorado beetle to pesticides. The influence of biotic and abiotic factors on the reduction of Colorado beetle numbers has been studied. With a view to possible biological control, predatory bugs (Perillus bioculatus and Podisus maculiventris) were introduced into Poland in 1959 and 1979. Research is also conducted on entomopathogenic fungi, parasitic nematodes, protozoans, spiroplasms and Bacillus thuringiensis.     

Integrated crop management, the basis for environment friendly crop protection of potatoes

Relatively large amounts of pesticides are needed to control diseases and pests in modern, intensive potato production. Integrated crop management offers a way of reducing the need for pesticides. It aims to reduce costs and improve the quality of the product and of the production methods, while maintaining soil fertility and the quality of the environment. The components of integrated crop management are described. Prevention of diseases and pests has high priority. If diseases or pests are present, non-chemical control methods are preferred and chemical control is based on economic criteria and the monitoring of the soil and crops. The contribution of integrated crop management to the control of two important fungal diseases, late blight (Phytophthora infestans), and stem canker (Rhizoctonia solani) and of one pest, potato cyst nematode (Globodera spp..) is described. The prospects for further development of integrated crop protection are discussed.     

Potato cyst nematodes in the Canary Islands: an epidemiologic model for the Mediterranean region1

This work describes studies done on the Canary Islands in order to support the elaboration of quarantine and control legislation for potato cyst nematodes which take into account the special agroecological characteristics of the Mediterranean region. The interest of the islands for epidemiological studies is based on the occurrence of the oldest potato crops in the Old World and the use of several local cultivars and traditional management cropping systems. Also, the environmental conditions allow field experiments to be performed throughout the year. The phytonematological problems of the potato crop on the Canary Islands is reported and the absence of Ditylenchus destructor, D. dipsaci, Nacobbus aberrans, Rotylenchulus reniformis and trichodorids pointed out. The cyst nematodes, Globodera rostochiensis and G. pallida were found to cause severe damage to the crop and were studied in detail by field trials at Tenerife. Continuous growing of the cv. Cara, with the H1 gene conferring resistance to G. rostochiensis (pathotypes Ro1 and Ro4), exerted selection pressure for G. pallida. Under the edaphic and climatic conditions of Tenerife, nematicide application was found to be inefficient for controlling potato cyst nematodes. Alternative control techniques based on traditional management systems and on the use of environmentally adverse conditions were investigated.     

Factors in the Success and Failure of Microbial Insecticides in Vegetable Crops

A search for patterns in the success and failure of microbial insecticides in vegetable crops was conducted through review of four case studies: the use of Bacillus thuringiensis (B.t.) var. tenebrionis for control of the Colorado potato beetle, the use of B.t. var. kurstaki for control of the diamondback moth, the use of various B.t.s for control of lepidopterous pests in tomatoes and celery, and the use of a granulosis virus for control of potato tuber moth. With success defined in terms of achievement of technical goals (efficacy), commercial goals (end-user and insecticide manufacturer satisfaction) and social, or public goals (environmental and health safety), only certain of the case studies could be judged a success. These successes shared a variety of features including: (1) use of the microbial insecticide as a component, rather than as the sole agent, in an integrated crop management program; (2) unavailability of conventional insecticides, due to insecticide resistance, lack of registered products or mandatory IPM programs, provided incentive for the use of microbial insecticides; (3) modification of the expectation that microbial insecticides will perform within the chemical paradigm – fast, lethal and on contact; (4) exploitation of all possible benefits of the microbial insecticide, including safety to natural enemies, as well as efficacy against the target insect, and (5) support from large private and public institutions in the form of research, grower education, scouting programs, subsidized production, and economic and legal incentives to the use of microbial insecticides.     

Current situation and prospects of potato production in Ukraine1

Total potato production has been maintained in Ukraine, but the share of production on private plots has recently increased from 65% to 97% and the efficiency of production has declined. Protection of the potato crop from pests has suffered particularly. Scientific institutions continue to breed new cultivars (particularly with resistance to wart and cyst nematodes), and the seed-potato production system is being maintained and improved. However, these systems were designed for large-scale production on collective and state farms and have to be adapted to the realities of private production.     

A biotechnological strategy involving monoclonal antibodies for improvement of potato farming by identification and quantification of potato cyst nematodes in soil samples1

The two closely related nematode species Globodera rostochiensis and G. pallida are one of the major problems encountered in potato cultivation. There is a spectrum of potato plant genes known, which confer resistance to these species and their pathotypes. Potato growing in The Netherlands has to follow strict rules to control spread of the pests. Since distinction between the two nematode species is difficult, a rapid and reliable identification method is needed to allow better use of existing and forthcoming resistant potato cultivars. The aims of this project were: (1) identification and partial purification of species-specific proteins from the nematodes, (2) production of species-specific monoclonal antibodies, and (3) development of a screening test for qualitative and quantitative determination of Globodera spp. in soil samples.     

Resistance as a Means of Control of the Potato Root Eelworm

A survey of the resistance of wild potatoes to the potato root eelworm and the use made of this property in potato-breeding is presented. Several biotypes of this parasite have been found to exist. The use of resistant varieties in the control of the potato root eelworm, in connection with other methods of control (crop rotation and soil disinfestation), is discussed.     

The Basis of Predictive Modelling for Estimating Yield Loss and Planning Potato Cyst Nematode Management

The basis of modelling yield loss and population dynamics relations of potato cyst nematodes is that both are strongly density-dependent. Potato cyst nematodes (PCN; Globodera pallida and G. rostochiensis) are particularly suitable for analysing such relationships because they have only one generation per year, potato is their only field host, the juvenile nematodes within the egg are very durable (up to 20 years persistence), and they hatch mainly in response to specific chemicals exuded from host roots. Small populations increase the most, up to 50-fold, when a potato crop is grown. Multiplication rates decrease as the population density increases because damage decreases root system size and increases competition so that very large populations may actually be decreased when potatoes are grown. The newly formed eggs have a ‘half-life’ of c.two years when non-host, rotational crops are being grown. Control is achieved largely by the use of rotation, the application of nematicidal chemicals, and growing resistant cultivars. As rotations are shortened, so PCN populations will be increased, and crop damage becomes more likely. Thresholds for damage vary with both soil type (greatest on sandy soils) and potato cultivar. Cultivars differ in their tolerance of PCN damage depending on how vigorously they grow, on their root sensitivity to damage from the PCN juveniles which invade close to root tips, on cultivar resistance which decreases the parasitic effect by reducing the numbers of developing PCN females, and on various environmental factors such as the amounts of fertiliser applied. The dependence of the yield-loss relationship on population density, soil type and cultivar effects has been described in a simple equation and assessed using field-trial data. Effects on yield are described in proportion to the PCN-free yield but the addition of information on expected yield (in tonnes ha⁻¹) in the absence of PCN renders this equation predictive. Nematicides are widely applied to infestations of potato cyst nematodes, both to prevent the crop from being damaged and to prevent population increase which could hazard the next potato crop in the rotation, but they are generally more effective at preventing the former than the latter. A complex equation has also been developed to model the population dynamics of PCN. This equation incorporates a factor for host-crop growth and tolerance (from the yield-loss equation) and also the effects of host resistance. This latter is particularly relevant to G. pallida, where all the resistance currently available is determined by minor genes and hence is ‘quantitative’ or ‘partial’. Effects of rotation and of nematicides can also be incorporated into this model. To provide a realistic prediction also requires accurate information on PCN population densities, species composition and distributions, and rates of PCN population decline between potato crops.     

Fungicide modes of action and resistance in downy mildews

Among oomycetes, Plasmopara viticola on grape and Phytophthora infestans on potato are agronomically the most important pathogens requiring control measures to avoid crop losses. Several chemical classes of fungicides are available with different properties in systemicity, specificity, duration of activity and risk of resistance. The major site-specific fungicides are the Quinone outside inhibitors (QoIs; e.g. azoxystrobin), phenylamides (e.g. mefenoxam), carboxylic acid amides (CAAs; e.g. dimethomorph, mandipropamid) and cyano-acetamide oximes (cymoxanil). In addition, multi-site fungicides such as mancozeb, folpet, chlorothalonil and copper formulations are important for disease control especially in mixtures or in alternation with site-specific fungicides. QoIs inhibit mitochondrial respiration, phenylamides the polymerization of r-RNA, whereas the mode of action of the other two site-specific classes is unknown but not multi-site. The use of site-specific fungicides has in many cases selected for resistant pathogen populations. QoIs are known to follow maternal, largely monogenic inheritance of resistance; they bear a high resistance risk for many but not all oomycetes. For phenylamides, inheritance of resistance is based on nuclear, probably monogenic mechanisms involving one or two semi-dominant genes; resistance risk is high for all oomycetes. The molecular mechanism of resistance to QoIs is mostly based on the G143A mutation in the cytochrome b gene; for phenylamides it is largely unknown. Resistance risk for CAA fungicides is considered as low to moderate depending on the pathogen species. Resistance to CAAs is controlled by two nuclear, recessive genes; the molecular mechanism is unknown. For QoIs and CAAs, resistance in field populations of P. viticola may gradually decline when applications are stopped.     

The Red Queen in a potato field: integrated pest management versus chemical dependency in Colorado potato beetle control

Originally designed to reconcile insecticide applications with biological control, the concept of integrated pest management (IPM) developed into the systems‐based judicious and coordinated use of multiple control techniques aimed at reducing pest damage to economically tolerable levels. Chemical control, with scheduled treatments, was the starting point for most management systems in the 1950s. Although chemical control is philosophically compatible with IPM practices as a whole, reduction in pesticide use has been historically one of the main goals of IPM practitioners. In the absence of IPM, excessive reliance on pesticides has led to repeated control failures due to the evolution of resistance by pest populations. This creates the need for constant replacement of failed chemicals with new compounds, known as the ‘insecticide treadmill’. In evolutionary biology, a similar phenomenon is known as the Red Queen principle – continuing change is needed for a population to persevere because its competitors undergo constant evolutionary adaptation. The Colorado potato beetle, Leptinotarsa decemlineata (Say), is an insect defoliator of potatoes that is notorious for its ability to develop insecticide resistance. In the present article, a review is given of four case studies from across the United States to demonstrate the importance of using IPM for sustainable management of a highly adaptable insect pest. Excessive reliance on often indiscriminate insecticide applications and inadequate use of alternative control methods, such as crop rotation, appear to expedite evolution of insecticide resistance in its populations. Resistance to IPM would involve synchronized adaptations to multiple unfavorable factors, requiring statistically unlikely genetic changes. Therefore, integrating different techniques is likely to reduce the need for constant replacement of failed chemicals with new ones. © 2014 Society of Chemical Industry     

Degeneration in sweetpotato due to viruses,virus‐cleaned planting material and reversion: a review

This review examines viral degeneration in sweetpotato in different regions of the World, particularly that caused by Sweet potato chlorotic stunt virus (SPCSV) and Sweet potato feathery mottle virus (SPFMV), comparing impacts on yield in single and complex infections of all the major viruses affecting the crop. How cultivars are generated and virus resistance are also covered, especially for Africa. The synergistic (SPCSV + SPFMV) sweet potato virus disease (SPVD) is amongst the most dramatic diseases of sweetpotato but its overall yield impacts may not be as high as is generally assumed. It is constrained by resistance, roguing and selection of symptomless planting material. Instead, the cumulative impact of individual and combinations of symptomless viruses may be globally greater. These include sweepoviruses and various potyviruses, of which the commonest is SPFMV. A number of aspects of virus‐cleaned planting stocks are identified, including reinfection rates, that need investigating before their use is considered as sustainable in developing countries. Popular East African cultivars appear to sustain their long‐term survival by reverting from symptomless infection. The likely biochemistry of this is discussed, and parallels are drawn with other crops. It is concluded that breeding for this attribute will be the best strategy for achieving long‐term control of most sweetpotato viruses.     

Control of blackleg and tuber soft rot of potato caused by Pectobacterium and Dickeya species: a review

This paper briefly reviews research on the causative agents of blackleg and soft rot diseases of potato, namely Pectobacterium and Dickeya species, and the disease syndrome, including epidemiological and aetiological aspects. It critically evaluates control methods used in practice based on the avoidance of the contamination of plants, in particular the use of seed testing programmes and the application of hygienic procedures during crop production. It considers the perspective of breeding and genetic modification to introduce resistance. It also evaluates the application of physical and chemical tuber treatments to reduce inoculum load and examines the possibility of biocontrol using antagonistic bacteria and bacteriophages.     

Glyphosate-resistant crops: adoption, use and future considerations

BACKGROUND: Glyphosate-resistant crops (GRCs) were first introduced in the United States in soybeans in 1996. Adoption has been very rapid in soybeans and cotton since introduction and has grown significantly in maize in recent years. GRCs have grown to over 74 million hectares in five crop species in 13 countries. The intent of this paper is to update the hectares planted and the use patterns of GRC globally, and to discuss briefly future applications and uses of the technology. RESULTS: The largest land areas of GRCs are occupied by soybean (54.2 million ha), maize (13.2 million ha), cotton (5.1 million ha), canola (2.3 million ha) and alfalfa (0.1 million ha). Currently, the USA, Argentina, Brazil and Canada have the largest plantings of GRCs. Herbicide use patterns would indicate that over 50% of glyphosate-resistant (GR) maize hectares and 70% of GR cotton hectares receive alternative mode-of-action treatments, while approximately 25% of GR soybeans receive such a treatment in the USA. Alternative herbicide use is likely driven by both agronomic need and herbicide resistance limitations in certain GR crops such as current GR cotton. Tillage practices in the USA indicate that > 65% of GR maize hectares, 70% of GR cotton hectares and 50% of GR soybean hectares received some tillage in the production system. Tillage was likely used for multiple purposes ranging from seed-bed preparation to weed management. CONCLUSION: GRCs represent one of the more rapidly adopted weed management technologies in recent history. Current use patterns would indicate that GRCs will likely continue to be a popular weed management choice that may also include the use of other herbicides to complement glyphosate. Stacking with other biotechnology traits will also give farmers the benefits and convenience of multiple pest control and quality trait technologies within a single seed.     

Seed-potato production of cultivars resistant to Globodera rostochiensis in Poland1

Changes in the production of Polish seed potatoes of cultivars that are resistant to potato cyst nematodes have been followed. Over the period from 1972 to 1998, 35 cultivars resistant to Globodera rostochiensis (pathotype RO₁) were introduced. Among them, one (Drop) was also resistant to Globodera pallida (PA₃) and a number had multiple resistance to diseases and nematodes. Planting of seed potatoes of these resistant cultivars concerned only 0.4% of the total potato area. Against a background of much reduced seed-potato production, the area planted with resistant cultivars fell by 47% over the years 1989/1997). However, the share of resistant cultivars in the total seed-potato area increased from 16% in 1989 to 47% in 1997, the most important cultivars being Lawina, Orlik, Ibis and Irga. In 1992/1993, resistant cultivars occupied only 6–8% of the total potato area.     

苏云金芽胞杆菌在马铃薯甲虫防治上的研究进展

马铃薯甲虫是重要的入侵害虫,严重威胁着我国粮食作物马铃薯的生产。苏云金芽胞杆菌是重要的农业害虫生防细菌,对马铃薯甲虫有良好的防治效果。本文围绕苏云金芽胞杆菌在马铃薯甲虫防治上的研究进展与应用进行综述。主要从马铃薯甲虫的入侵与防治手段、苏云金芽胞杆菌的晶体蛋白结构与杀虫机制、对马铃薯甲虫有活性的Bt毒蛋白研究进展、Bt毒蛋白对马铃薯甲虫的作用机制以及马铃薯甲虫对Bt毒蛋白的抗性机制等方面进行了综述。最后,从Bt新基因的挖掘和杀虫机理方面对苏云金芽胞杆菌在马铃薯甲虫防治上的研究进行了展望。     

Economic use of pesticides in the Ukraine

The total value of agricultural production in the Ukraine amounts to $30 billion, equivalent to 30% of the Gross Domestic Product (GDP). The annual cost of pesticide inputs is estimated to be $200–225 million. Herbicides and insecticides account for approximately 50% and 30% of pesticide use, respectively. The government has introduced a National Programme for the development of agricultural production over the next five to eight years. The programme envisages an expansion in agricultural production and pesticide use and a continuation of the move towards a free‐market economy. Improvements in crop yield and quality will benefit both the individual grower and the national economy. In the transition to the free‐market economy, growers require a clear understanding of present pesticide technology and crop production systems. A major change of attitude is required by all those people involved in providing and using pesticides to ensure that they are used both economically and safely. To address this issue, a Regional Academic Programme (REAP), involving Writtle College and Bila Tserkva State Agrarian University, has been initiated. © 2000 Society of Chemical Industry     

Bibliography of plant resistance to arthropods in vegetables, 1977–1991

This bibliography includes literature on plant resistance to insects and mites in vegetables from 1977 to 1991. It is arranged by plant family and crop plant, and has references to onions, garlic, cabbage and other crucifers, carrot, parsnip, celery, sweet potato, tomato, potato, eggplant, peppers, cucumber, melons, other cucurbits, spinach, lettuce, and various peas and beans. There is an index by arthropod species, a review of the literature, and tables listing references by subject area within plant resistance: screening; mechanisms; plant characteristics correlated with resistance; inheritance and traditional breeding programs; use of biotechnology; releases of resistant germplasm; comparisons of marketable yield; stability of resistance over different locations and insect populations; interactions with cultural methods and plant phenology, insecticide efficacy, and biological control; and effect on plant disease vectored by insects.     

Activation of defence responses to Phytophthora infestans in potato by BABA

Late blight caused by Phytophthora infestans is one of the most devastating diseases of the potato crop. Resistance breeding and current fungicides are unable to control the rapidly evolving P. infestans and new control strategies are urgently needed. This study examined mechanisms of dl ‐β‐aminobutyric acid (BABA)‐induced resistance (IR) in the potato–P. infestans system. Leaves from two cultivars that differ in their degree of resistance, Bintje and Ovatio, were analysed after foliar treatment with BABA. Rapid activation of various defence responses and a significant reduction in P. infestans growth were observed in leaves treated with BABA. In the more resistant cultivar, Ovatio, the activation was both faster and stronger than in Bintje. Microscopic analysis of leaves treated with BABA revealed induction of small hypersensitive response (HR)‐like lesions surrounded by callose, as well as production of hydrogen peroxide (H₂O₂). Molecular and chemical analyses revealed soluble phenols such as arbutin and chlorogenic acid and activation of PR‐1. These results show a direct activation of defence responses in potato, rather than priming as reported for other plant species. They also show that the efficiency of BABA‐IR differs between cultivars, which highlights the importance of taking all aspects into consideration when establishing new methods for disease management.     

The threat of root‐knot nematodes (Meloidogyne spp.) in Africa: a review

Meloidogyne species pose a significant threat to crop production in Africa due to the losses they cause in a wide range of agricultural crops. The direct and indirect damage caused by various Meloidogyne species results in delayed maturity, toppling, reduced yields and quality of crop produce, high costs of production and therefore loss of income. In addition, emergence of resistance‐breaking Meloidogyne species has partly rendered various pest management programmes already in place ineffective, therefore putting food security of the continent at risk. It is likely that more losses may be experienced in the future due to the on‐going withdrawal of nematicides. To adequately address the threat of Meloidogyne species in Africa, an accurate assessment and understanding of the species present, genetic diversity, population structure, parasitism mechanisms and how each of these factors contribute to the overall threat posed by Meloidogyne species is important. Thus, the ability to accurately characterize and identify Meloidogyne species is crucial if the threat of Meloidogyne species to crop production in Africa is to be effectively tackled. This review discusses the use of traditional versus molecular‐based identification methods of Meloidogyne species and how accurate identification using a polyphasic approach can negate the eminent threat of root knot nematodes in crop production. The potential threat to Africa posed by highly damaging and resistance‐breaking populations of ‘emerging’ Meloidogyne species is also examined.     

Dickeya species: an emerging problem for potato production in Europe

Dickeya species (formerly Erwinia chrysanthemi) cause diseases on numerous crop and ornamental plants world‐wide. Dickeya spp. (probably D. dianthicola) were first reported on potato in the Netherlands in the 1970s and have since been detected in many other European countries. However, since 2004–5 a new pathogen, with the proposed name ‘D. solani’, has been spreading across Europe via trade in seed tubers and is causing increasing economic losses. Although disease symptoms are often indistinguishable from those of the more established blackleg pathogen Pectobacterium spp., Dickeya spp. can initiate disease from lower inoculum levels, have a greater ability to spread through the plant’s vascular tissue, are considerably more aggressive, and have higher optimal temperatures for disease development (the latter potentially leading to increased disease problems as Europe’s climate warms). However, they also appear to be less hardy than Pectobacterium spp. in soil and other environments outside the plant. Scotland is currently the only country in Europe to enforce zero tolerance for Dickeya spp. in its potato crop in an attempt to keep its seed tuber industry free from disease. However, there are a number of other ways to control the disease, including seed tuber certification, on‐farm methods and the use of diagnostics. For diagnostics, new genomics‐based approaches are now being employed to develop D. dianthicola‐ and ‘D. solani’‐specific PCR‐based tests for rapid detection and identification. It is hoped that these diagnostics, together with other aspects of ongoing research, will provide invaluable tools and information for controlling this serious threat to potato production.