Potato Beetle Leptinotarsa Decemlineata Say Research Articles

Potato productivity on the background of the entomopathogenic fungus <i>Metarhizium robertsii</i> application in production trials

For the first time in Western Siberia (Novosibirsk region), two-year production trials of an experimental prototype of a drug based on the entomopathogenic fungus Metarhizium robertsii have been conducted. Strain P-72 isolated from the dead larvae of Colorado potato beetle Leptinotarsa decemlineata Say from the collection of microorganisms of the Institute of Systematics and Ecology of Animals of the Siberian Branch of the Russian Academy of Sciences was used in this work. Species identification of the fungus was performed based on sequencing of the elongation factor gene region EF1α. The ability of the preparation to significantly increase the parameters of potato yield structure elements throughout the whole vegetation period was shown. A reliable increase in the number of surviving sprouts by 1.4 times, the number of stems and tubers by 1.5 times was found. The growth-stimulating effect of using the preparation based on entomopathogenic fungus was manifested in the increase of plant weight by the flowering phase. The average yield increase for two years amounted to 36.0% in the variant with application of M. robertsii significantly exceeding the productivity of potatoes in the control. The level of profitability of potato production with the use of entomopathogenic fungus M. robertsii increased to 92.0% (with 50.0% in the control) due to the increase in gross yield and improved quality of marketable products. Infestation of new harvest tubers with rhizoctoniose significantly decreased in the variant including treatment with entomopathogenic fungus: the number of tubers with sclerotia decreased 2.8 times compared to the control, which eventually led to an increase in the number of healthy tubers and a significant (2.5 times) decrease in the sclerotial index.

RESISTANCE OF PROMISING POTATO VARIETIES TO THE MOST IMPORTANT BEETLE PESTS IN THE CONDITIONS OF THE NORTHWEST OF THE EUROPEAN PART OF RUSSIA AND THE SOUTH OF THE FAR EAST

The article provides the results of evaluation of 10 promising potato varieties for the group resistance to the Colorado potato beetle Leptinotarsa decemlineata Say and to the Potato ladybird Henosepilachna vigintiomaculata Motsch. The researches were performed by field methods with artificial colonization of plants of the studied varieties in 1st instar, in the quantity of 30–100 larvae for each potato variety, and were held: according to the Colorado beetle – on experimental field of the All-Russian Research Institute for Plant Protection (Saint-Petersburg – Pushkin); according to the potato ladybird – on experimental field of the Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaikа (Primorsky Krai, Ussuriysk). Examples of potato varieties from the new assortment confirm the significant similarity (parallelism of developing) of the trophic reactions of both species, which have the same type of nutrition and many similar features of development biology. As the first result, it has shown that the Severnyi and Smak varieties have a group resistance to both phytophages with a survival of 10–20% of larvae before pupation. In other side, the Avgustin and Dalnevostochnyi varieties noted as a favourable for the development of these pests with a survival of 45–75% of larvae.

Breeding the predatory bug Podisus maculiventris Say to protect potatoes from Leptinotarsa decemlineata Say

The predator Podisus maculiventris Say is a representative of the order Hemiptera, family Pentatomidae. This insect is promising in the battle against the Colorado potato beetle Leptinotarsa decemlineata Say. For the successful use of P. maculiventris in the climatic conditions of the Russian Federation and other countries where this predator isn’t found, it is necessary to develop methods of its artificial reproduction. The paper provides information on the selection of food based on the use of phytophagous insects and pests. Among the subjects Galleria mellonella L. caterpillars, Tenebrio molitor L. larvae and pupae, Ephestia kuehniella Zll. caterpillars, as well as Zophobas morio Fabr larvae were used. As a result of the experiment, T. molitor was recognized as the most effective insect prey in terms of biological and economic indicators. When using Tenebrio molitor, the imago yield of P. maculiventris amounted to 81.0-90.5%, which was the best indicator in comparison with other options.

SPREADING OF COLORADO POTATO BEETLE RESISTANCE TO CHEMICAL INSECTICIDES IN SIBERIA AND HISTORY OF ITS SETTLING IN THE SECONDARY AREA

Data obtained from toxicological analysis of sensitivity to insecticides in Colorado potato beetle Leptinotarsa decemlineata Say (Coleoptera, Chrysomelidae) in Novosibirsk region evidenced presence of multiresistance to organophosphorus compounds (OPC), neonicotinoids and nereistoxins. High level of sensibility to pyrethroids and phenylpyrazoles is a peculiarity of Novosibirsk population of Colorado beetle. These data as well as high phenotypical similarity of adults from Novosibirsk region and Kazakhstan suggest that population complex of Colorado beetle in Kazakhstan had formed from part of the “settling wave” which did not fall under wide-scale pyrethroids application in the middle zone of Russia in 1980th. Probably,further spreading of this part of Kazakhstan population northwards led to formationof new zones of species naturalization in Siberia.

Potential of Colorado Potato Beetle (Coleoptera: Chrysomelidae) to Adapt to Alternative Host Plants.

Twelve selected cultivated or wild solanaceae (Solanum dulcamara, Solanum nigrum, Solanum villosum, Solanum lycopersicum, Solanum muricatum, Solanum melongena, Datura innoxia, Datura metel, Physalis spp., Capsicum annuum, Nicotiana alata, and Petunia spp.) (all species Solanales: Solanaceae) were tested as potential alternative host plants against Solanum tuberosum for a local population of the Colorado potato beetle Leptinotarsa decemlineata Say (CPB) in Estonia. Some CPB populations in America and southern Europe accept most of these plants. However, geographically isolated populations of beetles can differ in their acceptance of new host plants. Migrants from the southern Europe supplement Estonian beetle population regularly, so individuals may differ in their host plant preferences. S. melongena and S. dulcamara were well accepted by the beetles, Lycopersicum spp. (Solanales: Solanaceae) and N. alata were intermediate, and S. villosum and S. nigrum were least accepted. The beetles rejected S. muricatum, Physalis spp., C. annuum, Petunia spp., and D. metel. First-instar larvae completed a full life cycle only on S. dulcamara, N. alata, S. lycopesicum, S. melongena, although their development rate was slower, mortality was higher and emerging adults were underweight relative to those that fed on S. tuberosum. The fourth-instar larvae were less sensitive in relation to food. We found that S. dulcamara as a native plant could provide resources for CPB during early and late season. At the same time, the cultivated S. melongena would be suitable plant species for further testing as dead-end crop for integrated pest management.

Defense Responses and Changes in Symbiotic Gut Microflora in the Colorado Potato Beetle Leptinotarsa decemlineata under the Effect of Endophytic Bacteria from the Genus Bacillus

Phytophagous insects and host plants have a complex of microsymbionts and make up a united co-evolving system with them. Microsymbiotic complexes are actively involved in stress responses of macrosymbionts. We established that a treatment of potato plants with endophytic bacterial strains Bacillus thuringiensis var. thuringiensis-5689, B. th. var. kurstaki-5351, and Bacillus subtilis 26D decreased the survival rate of the plant feeder, Colorado potato beetle Leptinotarsa decemlineata Say. The B. th. strains suppressed phenoloxidase and acetylcholinesterase activities in the beetle hemolymph. An antagonistic relationship was found between endophytic bacteria B. subtilis 26D and beetle symbiotic bacteria from the genera Acinetobacter and Enterobacter, with the former being able to suppress the growth of endophytic colonies. The recombinant B. subtilis strain 26D Cry, containing the B. th. var. kurstaki δ-endotoxin cry1Ia gene, combined the ability of the original B. subtilis 26D strain to suppress the development of beetle symbionts and immune responses with a production of the Cry toxin, thus leading to a high mortality of the phytophage.

Phenology and overwintering of the Colorado potato beetle Leptinotarsa decemlineata Say in 2008–2015 in Estonia

ABSTRACTBefore its establishment in Estonia at the beginning of the twenty-first century, the Colorado potato beetle Leptinotarsa decemlineata Say was a notifiable quarantine pest for many years. In high-latitude environments it encounters strong evolutionary pressure to adapt to low temperatures due to high overwintering mortality and periodic influx of new individuals from more southern populations. Our study focused on gathering evidence for such a range shift leading to the formation of a permanent local population. The phenology and overwintering success of beetles was investigated from 2008 to 2015. Depending on weather conditions in the different years, the overwintered beetles emerged from the soil from the beginning of May to mid-June. Over 700 degree days accumulated in 2010, 2011, 2013 and 2014 exceeding the limit needed for development of two generations. However, food supply and temperature distribution in the growing period enabled development of the second complete generation only in 2010 and 2013. Survival of overwintering beetles in field conditions varied between 18% and 47% in the different years. Winter mortality was not associated with low air temperature in any year as snow cover provided the necessary protection and winter soil temperatures at the depth of 30 cm remained at around 0°C for the duration of the whole observation period, with only some records as low as −3.5°C. The survival of overwintering beetles is more likely defined by factors other than low temperature. As a result of periodic invasions of beetles with naturally lower cold resistance originating from southern regions, the structure of the overwintering population in Nordic temperate conditions is not homogeneous. Moreover, this may also be derived from cultural practices, as commercial producers regularly apply agrochemicals while organic growers avoid them.

Assortative mating and intrapopulation polymorphism maintenance in natural populations and laboratory lines of insects

Speciation is a microevolutionary process that starts with intraspecies differentiation, followed by the establishment of reproductive isolation. One of the intrinsic isolating factors causing physiological isolation is assortative mating. As a result of many years of observations of the natural populations on the territory of the South Urals (the Bashkortostan Republic) and long-term laboratory experiments, we revealed assortative mating in populations of the potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae). The assortativity of mating manifested itself as a statistically significant deviation from the normal distribution of the frequencies of imago pairs belonging to three morphological types, which are defined by the degree of integument pattern melanization, namely, the achromists (A), melanists (M), and intermediate type (I). In copulo, we have not detected mating between achromist males (A) and melanist females (M), with the active choice in this case belonging to males. Under the laboratory conditions, with a sampling of 40 artificially formed pairs, we revealed statistical differences in the longevity and breeding performance of imagoes belonging to different morphological types. Achromists and melanists were characterized by a statistically higher longevity, almost two times higher than that in individuals of the intermediate type. Females of the intermediate type showed statistically higher fecundity in the homonomous crosses than achromists and melanists. It was demonstrated that the viability of the progeny also differed statistically in different pairs. The highest viability was detected for the progeny obtained from the type A and type I females. The observed differences indicated the existence of different reproductive strategies in studied species populations. In the S laboratory line of the common house fly Musca domestica L. (Diptera: Muscidae), we detected individuals with different reproductive strategies associated with longevity. The maximum longevity in two inbred lines, Sh28 (short-living) and L2 line (long-living), isolated from the S line showed a statistical, almost twofold difference. Mass reproduction time is confined to the first or second week of the imago stage in the short-living fly line; it is shifted to the third or fourth week in long-living flies. In reciprocal crosses between the lines, we detected a dramatic decrease in the fecundity of the females and a decrease in the viability of the hybrid females. The results confirm the essential role of assortative mating and frequency-dependent selection in the maintenance of the intrapopulation diversity.

The influence of climatic changes on range expansion and phenology of the Colorado potato beetle (Leptinotarsa decemlineata, Coleoptera, Chrysomelidae) in the territory of Russia

Analysis of expansion of the potential range of the Colorado potato beetle Leptinotarsa decemlineata Say and shifts of the zones with different number of generations per season was carried out using cartographic modeling. The shifts were caused by the climate changes in Russia observed in recent decades. The annual sum of effective mean daily air temperatures was selected as the main criterion which determines both the suitability of the area for the Colorado potato beetle and the number of generations that can be produced in one season. The main range expansion was observed in the east direction, and the greatest changes took place during expanding of the zones with the possible development of one or two generations. The boundaries of the zone where development of three generations is possible changed to a lesser degree.

Estimation of the role of predatory epigeic beetles (Coleoptera: Carabidae, Staphylinidae) in regulation of pest population density in agroecosystems

Epigeic polyphagous predatory beetles can regulate the pest abundance. The range of population densities at which regulation is possible is specific to each predator-prey subsystem and can be determined experimentally. In the subsystem of ground and rove beetles (Carabidae and Staphylinidae) and the cabbage maggot Delia brassicae Bouche and in that of Carabus hampei Kust. and the Colorado potato beetle Leptinotarsa decemlineata Say, regulation occurs at low pest densities: in the former subsystem, at oviposition rates not exceeding 3 eggs per day per plant, and in the latter, at the pest density varying from 1 to 36 eggs per potato plant. Within these density ranges, both the absolute and relative number of pest individuals eliminated by the predatory beetles increase. The maximum fraction of the pests destroyed by these entomophages is observed at medium prey population densities, which corresponds to functional response of type III (Holling, 1965).

Wounding, insect chewing and phloem sap feeding differentially alter the leaf proteome of potato, Solanum tuberosum L.

BackgroundVarious factors shape the response of plants to herbivorous insects, including wounding patterns, specific chemical effectors and feeding habits of the attacking herbivore. Here we performed a comparative proteomic analysis of the plant's response to wounding and herbivory, using as a model potato plants (Solanum tuberosum L.) subjected to mechanical wounding, defoliation by the Colorado potato beetle Leptinotarsa decemlineata Say, or phloem sap feeding by the potato aphid Macrosiphum euphorbiae Thomas.ResultsOut of ~500 leaf proteins monitored by two-dimensional gel electrophoresis (2-DE), 31 were up- or downregulated by at least one stress treatment compared to healthy control plants. Of these proteins, 29 were regulated by beetle chewing, 8 by wounding and 8 by aphid feeding. Some proteins were up- or downregulated by two different treatments, while others showed diverging expression patterns in response to different treatments. A number of modulated proteins identified by mass spectrometry were typical defense proteins, including wound-inducible protease inhibitors and pathogenesis-related proteins. Proteins involved in photosynthesis were also modulated, notably by potato beetle feeding inducing a strong decrease of some photosystem I proteins. Quantitative RT PCR assays were performed with nucleotide primers for photosynthesis-related proteins to assess the impact of wounding and herbivory at the gene level. Whereas different, sometimes divergent, responses were observed at the proteome level in response to wounding and potato beetle feeding, downregulating effects were systematically observed for both treatments at the transcriptional level.ConclusionsThese observations illustrate the differential impacts of wounding and insect herbivory on defense- and photosynthesis-related components of the potato leaf proteome, likely associated with the perception of distinct physical and chemical cues in planta.

Change in the polymorphism level in populations of the Colorado potato beetle

Data on changes in the phenetical structure of populations of the Colorado potato beetle Leptinotarsa decemlineata Say in the Southern Urals (territory of the Republic of Bashkortostan) are presented. A decrease in the level of phenetical polymorphism between 1994 and 2002 was registered. The results of laboratory experiments give us good grounds to believe that the selective effect of insecticides is the main reason for the decrease in the level of intrapopulation polymorphism.

Phenotypic variability of environmental isolates of the entomopathogenic fungus Beauveria bassiana

A total of 35 isolates of Beauveria bassiana (Bals.) Vuill. isolates obtained from various insects of Novosibirsk oblast were investigated. The fungal morphotypes were found to include cultures of high, medium, and low virulence. Low correlation (r 0. 74) was revealed between the virulence of the isolates to the potato beetle Leptinotarsa decemlineata Say and the locusts Calliptamus barbarus Costa and Locusta migratoria L. Isolates obtained from insects of the same species in the same site may differ significantly in virulence.

Leaf surface compounds of the potato (Solanum tuberosum) and their influence on Colorado potato beetle (Leptinotarsa decemlineata) feeding

The sampling behavior of the Colorado potato beetle Leptinotarsa decemlineata Say (CPB) involves examination of the surface of potato leaves. It has been suggested that leaf surface compounds (volatiles and cuticular waxes) may be involved in host-plant recognition, acceptance or discrimination. Here we report on the effect of leaf surface extracts of six Polish commercial potato varieties on CPB feeding. We tested the influence of potato leaf surface extracts on CPB adult and larval feeding, then separated the extracts with HPLC, and finally tested the effect of the HPLC-separated fractions on CPB feeding. The bioassays were performed using potato leaf discs deprived of their original surface compounds. Applied to test discs at concentrations ten times higher than natural (10 leaf area equivalent), the extracts deterred CPB adults and larvae from feeding. HPLC-separated fractions composed of alkanes, sesquiterpene hydrocarbons, wax esters, benzoic acid esters, fatty acid methyl, ethyl, isopropyl and phenylethyl esters, aldehydes, ketones, methyl ketones, fatty acids, primary alcohols, β-amyrin and sterols did not affect adult CPB feeding. Similarly, alkanes, sesquiterpene hydrocarbons, wax esters, methyl ketones, sesquiterpene alcohols and secondary alcohols had no effect on larval CPB feeding. The sterol fraction (cholesterol, β-sitosterol and stigmasterol) acted as a phagostimulant to CPB larvae. We isolated a fraction demonstrating a phagodeterrent effect on CPB adults and larvae. The qualitative composition of the deterrent fraction was quite similar in all potato extracts, but there were quantitative differences between the varieties. Much further work is needed to identify the compounds that can produce the deterrent effect.

Microevolutionary processes in a population of the Colorado potato beetle (Leptinotarsa decemlineata Say.) at feeding by various cultivars of the potato

In regions of the Ukraine, nine phenetic forms of the Colorado potato beetle Leptinotarsa decemlineata Say. of various resistance to varieties, species and the genetically modified cultivars of the genus Solanum have been discovered. In the beetle populations, groups of preadapted individuals have been revealed. Their presence is considered as point events, indicating the beginning of the microevolutionary processes of the formation of the resistant beetle populations. As launching mechanisms of these processes, the new vectors of directional selection can serve, in particular, the genetically modified varieties of the potato composing a new trophical niche of the pest.

Response to host plant odors and aggregation pheromone by larvae of the Colorado potato beetle on a servosphere

Using a servosphere (locomotion compensator), locomotory behavior of Colorado potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) larvae was measured in detail in response to pulsed and non-pulsed odors of hostplant and conspecific pheromone. Second instars showed decreased straightness of movement, and all larvae showed decreased speed, in response to potato odor. Change in straightness by 2nd instars was also significantly affected by the interaction of pheromone and pulsing treatments. Fourth instars showed increased positive anemotaxis in response to the combined hostplant and pheromone odors. To our knowledge, this is the first demonstration of larval behavioral responses to adult pheromone in a holometabolous insect.

Evaluation of the effects of two Beauveria bassiana (Balsamo) Vuillemin strains on the development of Coleomegilla maculata lengi Timberlake (Col., Coccinellidae)

Abstract: The effect of the fungus Beauveria bassiana (Balsamo) Vuillemin, strains ATCC 44860 and ARSEF 2991, on the development of the spotted ladybird beetle Coleomegilla maculata lengi Timberlake larvae and pupae was evaluated at concentrations of 102, 104, 106 and 108 blastospores/ml. Duration of development of C. maculata was measured when fed on contaminated pollen or when allowed to prey on first and second instars Colorado potato beetle Leptinotarsa decemlineata Say (Col., Chrysomelidae) larvae treated by pulverization. The two B. bassiana strains exhibited different effects on the duration of development of C. maculata. Pollen or Colorado potato beetle larvae treated with B. bassiana strain ATCC 44860 increased the C. maculata development time, whereas Colorado potato beetle larvae treated with strain ARSEF 2991 reduced development time but pollen treated with the same strain had no effect.

Heterogeneity of twoBeauveria bassiana strains revealed by biochemical tests, protein profiles and bio-assays ofLeptinotarsa decemlineata (Col.: Chrysomelidae) andColeomegilla macultata lengi (Col.: Coccinellidae) larvae

Biochemical profiles on API Rapid CH* strips and protein profiles on polyacrylamide gels in the presence of sodium dodecyl sulfate were used to distinguish two strains of the entomopathogenic fungusBeauveria bassiana (Balsamo) Vuillemin, ARSEF 2991 and ATCC 44860. Next, the toxicity of these two strains was determined at concentrations of 102, 104, 106 and 108 blastospores/ml on larvae of the Colorado potato beetleLeptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) and of its predator, the spotted ladybird beetle,Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae).

Some properties of hemolymph esterases from [formula omitted] Say

Hemolymph JH esterases, capable of hydrolyzing C-18 and C-16 juvenile hormones (JH I and JH III respectively), are present in the hemolymph of the Colorado potato beetle Leptinotarsa decemlineata Say. Similar kinetics of degradation were found for JH I and JH III. The apparent Km value for JH III esterase was determined. Two JH analogues, an ethylester without the 10, 11-epoxide group (ZR512) and an isopropylester (ZR515) were not hydrolyzed by hemolymph esterases. JH-esterases were found to be insensitive to 10 −3M diisopropylfluorophosphate (DFP), while general carboxy-esterases were totaly inhibited. Triton X-100 (0.1%) appeared to have the opposite effect. An electrophoretic study of the esterases showed that a number of JH-specific esterases exist in the hemolymph. JH-specific hemolymph esterases occur during all the stages tested, but show characteristic changes in activity during development.