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"Push-Pull" is an inexpensive and eminently practical strategy designed for developing countries in order to exploit sound principles of chemical ecology for agricultural pest management. This strategy is specifically suitable for small holder farmers. Their experience can easily be integrated into existing farming practices in their immediate environment. "Push-pull" within one and a half decades became widely established and meanwhile is greatly beneficial to practitioners in East Africa, mainly Kenya. The classical push-pull approach used for applied plant-insect management was pioneered by Khan and Pickett (2000) and subsequent papers of Pickett (2003) and Khan et al. (2006, 2008). Relevant plant species explored so far were maize or sorghum intercropped with other East African plants (Desmodium spp. resp. Melinis minutiflora) possessing natural chemicals repellent resp. attractive for stem borer moths Chilo partellus (Lepidoptera), whereby Desmodium spp. was grown inside the maize rows while M. minutiflora surrounded it. Both simultaneous actions combined resulted in a significant decrease of stem borers in the area to be protected. A benefit to cost ratio of 2.5 was realized. Within a period of 15 years the number of subscribing farmers substantially increased from a few dozen to more than 80,000 in 2014. Two experiments along the paths of chemical ecology were undertaken between Sept 2012 and Feb 2013: One was designed to investigate if the legume D. intortum known to produce repellent volatiles against stem borer moths induces defence in Zea mays varieties. We looked at two open-pollinated farmers' varieties and two commercial hybrid varieties suspecting the farmers' varieties to be responsive rather than the hybrids. However, no defence induction was detected in this study so far. This could be explained by an insufficient production of defence inducing volatiles in leaves of D. intortum whereas flowers might produce a sufficient response. More detailed study is needed. A second approach made use of species-specific insect monitoring traps baited with highly specific female sex pheromones for attracting and monitoring destructive insect pests. The female sex pheromone (8-methyl-decane-2-ol propanoate) of Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) (Western Corn Rootworm) is readily available as bait in the "Metcalf sticky cup trap" for trapping males, an extraordinarily sensitive technique for monitoring the presence or absence of male beetles in a given area. Li et al. (2006) had argued for the likelihood of easy immigration of this cosmopolitan maize pest into East Africa. Our results, however, so far indicate the absence of a local population in the area of Mbita, while not excluding its presence at Nairobi or Mombasa. Both investigations contribute to different aspects of Kenyan economic development and may be seen as two independent but complementary contributions towards livelihood improvement of small holder farmers in Kenya.

Neem plants (Rutales: Meliaceae) are well known for their multitude of human benefits in various fields. Specifically well investigated are the Indian neem tree Azadirachta indica A. Juss., the Thai neem A. siamensis Val., the originally Malaysian/Philippinean neem A. excelsa (Jack) and, as a close relative, the Persian lilac, Melia azedarach. The major and most active natural products are azadirachtin, salannin, nimbin and marrangin from Azadirachta species, and azadirachtin analogues like meliantriol from Melia species. Neem fruits, leaves, bark, and roots have specific virtues. They have been traditionally exploited for a considerable part of human history and are documented in Sanskrit texts. Due to human activity in trade and travel both at land and sea, the plant species has been distributed around the globe and is cultivated in many tropical, and subtropical regions. A multitude of natural products of neem have been isolated, chemically characterized or identified, and investigated for their properties in the management of insects, Acarina, Crustacea, nematodes, bacteria, fungi, viruses and soil fertility (for reviews see Kraus, 2002; Schmutterer, 2002A; Rembold, 2002; Koul, 2004; Schmutterer and Huber, 2005; Kleeberg and Strang, 2009; Hummel et al., 2008, 2011, 2012). Neem products are virtually nontoxic, compatible with beneficial insects, pollinators and bees. They are environmentally benign, sustainable, renewable, and of a price affordable for developed countries. In conclusion, neem is a prime example of a natural resource with many beneficial applications in agriculture, human and veterinary medicine. So far, its use is practically free of resistance problems which are frustratingly prevalent in many areas of synthetic insecticide and drug development. Investigating more neem applications will increase future human welfare and health while being of general ecological benefit to the planet.

Cydia pomonella (Lep.: Tortricidae), the codling moth, is an apple, pear, quince and walnut pest with considerable impact on horticultural production systems in many parts of the world. In commercial apple production, it is responsible for a yearly damage level of 40 billion dollars. In response to the need of tight codling moth control there are several options for intervention by pest managers in commercially operated orchards. Spray and count methods have been used for decades with success, but at considerable external costs for the integrity of ecological cycles. Also, problems with pesticide residues and with resistant strains are an issue of concern. For environmental reasons, toxicological means are discounted here. Instead, flight curves based on sex pheromone trapping and monitoring are preferred means towards determining the optimal timing of interventions by biotechnical and biological control methods. Finally, ecological reasons are discussed for vastly different population levels of C. pomonella developing in closely neighboring field sections which operated under different environmental management.

As Wudtke and colleagues predicted and Hummel and colleagues later confirmed, the Western corn rootworm Diabrotica v. virgifera LeConte (Coleoptera: Chrysomelidae) (WCR) had shown the ability to expand northward from South and Eastern into Central Europe. Decades earlier WCR had done the same in North America. Yet, European entomologists erroneously assumed they would be somehow magically protected from such aggressive moves of WCR. Meanwhile we know better: Southern Germany is infested, and also many East European countries are victims of these Northern and also Eastern advances. In Germany, neither speed nor extent of such advances is well defined. Jumping advances similar to earlier spreading episodes may be the rule, but they are not well predictable. In this report, we argue for a persistent northbound trend of WCR.

Pheromone effects discovered some 130 years, but scientifically defined just half a century ago, are a great bonus for basic and applied biology. Specifically, pest management efforts have been advanced in many insect orders, either for purposes or monitoring, mass trapping, or for mating disruption. Finding and applying a new search algorithm, nearly 20,000 entries in the pheromone literature have been counted, a number much higher than originally anticipated. This compilation contains identified and thus synthesizable structures for all major orders of insects. Among them are hundreds of agriculturally significant insect pests whose aggregated damages and costly control measures range in the multibillions of dollars annually. Unfortunately, and despite a lot of effort within the international entomological scene, the number of efficient and cheap engineering solutions for dispensing pheromones under variable field conditions is uncomfortably lagging behind. Some innovative approaches are cited from the relevant literature in an attempt to rectify this situation. Recently, specifically designed electrospun organic nanofibers offer a lot of promise. With their use, the mating communication of vineyard insects like Lobesia botrana (Lep.: Tortricidae) can be disrupted for periods of seven weeks.

Organic nanofibers have a history of technical application in various independent fields, including medical technology, filtration technology, and applications of pharmaceuticals via inhalation into the lungs. Very recently, in a joint effort with polymer chemists, agricultural applications have been added to this list of priorities. The aim is finding novel approaches to insect control. Pheromones, dispensed in a quantifiable way, are being used here in disrupting the mating communication between male and female pest insects, e.g. the European grapevine moth Lobesia botrana (Lepidoptera: Tortricidae), where current dispenser technology does not fully meet the high expectations of growers and environmentalists with respect to longevity of constant release, self decomposition, mechanical distribution, renewability as well as sustainability of resources. The methodology of electrospinning is exhaustively covered by Greiner and Wendorff (2007), with technical details reported by Hellmann et al. (2009), Hein et al. (2011), and Hummel et al. (2010). Wind tunnel studies were run within a tunnel with adjustable laminar flow and 0.5 m/sec air velocity. Mass losses of the electrospun fiber bundles were determined with a sensitive analytical balance 2-3 times per week and recorded as time vs. mass change. CLSA experiments were performed with a self developed glass apparatus (Lindner, 2010) based on various suggestions of previous authors. Microgram quantities of volatile pheromone (E,Z)-7,9-Dodecadienylacetate were absorbed on a filter of rigorously purified charcoal and desorbed by repeated micro extraction with a suitable solvent mixture. Aliquots of the solution were subjected to temperature programmed capillary GLC. Retention times were used for identification, whereas the area covered by the pheromone peak originating from a FID detector signal was integrated and compared with a carefully calibrated standard peak. Since these signals were usually in the low nanogram range, several replications were averaged for statistical improvement. - Thermogravimetric analysis between ambient temperature and 500 degrees C provided a series of degradation curves where the diagram contained information on the evaporation of pheromone alone, polymer fiber alone and pheromone included in the fiber.- Microscopic investigations resulted in pictures of nanofibers from which the overall morphology and the fiber dimensions could be quantified. Organic nanofibers loaded with the grapevine moth pheromone have been well characterized by 5 different lab methods, followed by field bioassays reported elsewhere in these communications volumes (HUMMEL et al., 2011). This comprehensive analytical approach to fiber characterization is new and will be further refined. The federal agency JKI Berlin subjected the pheromone loaded organic fibers to various independent toxicological and ecotoxicological tests and found no adverse side effects.

Beginning fifty years ago, the search for suitable dispensers containing insect pheromones grew with the availability of these synthetic biotechnical tools. Many economic entomologists and application engineers dearly wish they had the "smart, intelligent and ideal dispenser". More or less suitable approximations are available commercially, but none so far meets all demands. Under economic strictures, novel inexpensive systems would be advantageous with release characteristics tailored to the specific life histories of pest insects, the plants considered and the numerous requirements of growers alike. Simultaneously, their field distribution should be mechanizable and be accomplished by one (or very few) application runs. The dispensers should be biodegradable, biocompatible, sustainably applicable, and they should be based on renewable resources. This report presents first results of a novel organic, electrospun nanofiber dispenser with dimensions in the upper nanometer range. Its load of pheromone can be adjusted to be sufficient for 7 weeks of constant disruptive action in vineyards and can be directed against the European Grape Vine Moth Lobesia botrana (Lepidoptera: Tortricidae) which here serves as a readily available model. Mating disruption in L. botrana and the related Eupoecilia ambiguella is a well studied and developed engineering process. Equally, nanofiber production by electrospinning (for a comprehensive review see Greiner and Wendorff, 2007A, B) is well known and already has numerous applications in filtration technology, air conditioning, and medical wound dressing. Our goal was to bring together and successfully mate these (partly incompatible) technologies via technical tricks of a proprietary nature. Even though the lifetime and effectiveness of currently available nanofibers still must be doubled, the rather complicated system of their production and analysis is known well enough to identify the parameters that need future adjustment. Another challenge is the mechanical distribution of the fibers in the vineyards by suitable machinery. Also, in this respect, certain technical leads are available for future development.

Diabrotica virgifero virgifera (Col.: Chrysomelidae) (western corn rootworm, WCR) unfortunately is now a firmly established European maize pest without indigenous natural enemies. Twenty years after its first introduction into Europe by traffic and trade, eradication is wishful thinking and not longer a viable option. Instead, European legislation calls for toxicological emergency measures on a case by case basis where and when new infestations occur either by new invasions from the native Americas or by introductions from other European countries. It is unclear at which point in time such treatment systems will break down because of development of resistant strains or by other complications of this seemingly unstable situation. Rather than proceeding as usual, sustainable biological, biotechnical and cultural methods should be practiced. Prominent among them are trapping and survey with attractants in conjunction with traditional crop rotation and phytosanitation.

Ergographic analysis is a new approach for qualitative assessment and quantitative depiction of publication records of prolific authors. For proving the merits of ergographic analysis, the method is applied to the work of 3 scientists who are well known for their individual contributions to basic and applied entomology, insect toxicology, insect biochemistry, and chemical ecology including integrated pest management. Authors thus considered are R.L. Metcalf (1916-1998), H. Schmutterer (born 1926) and P. Karlson (1918-2001). Ergograms obtained through ergographic analysis are graphic presentations of when, which, and how many papers appeared within the author's lifetime (two-dimensional ergogram), and how parallel or subsequent strands of distinct thematic interests and subject areas intertwine or follow each other over time (three-dimensional ergograms). Unlike conventional printed bibliographies which have a tendency to be SUMMARY, rather unwieldy and boring, ergograms provide easy graphic access to information. They can be understood and interpreted at first glance and with a conceptual clarity so far unknown from conventionally printed reference lists.

Roots of Stemona tuberoso have been extracted by using fixed-bed contacting method with serial and parallel technique. In order to extract secondary metabolites from roots of Stemona sp., various organic solvents with different polarities were employed. Optimal solvents for the extraction of effective ingredients from root were determined. The results showed that in most cases the yields of crude extract were highest by using parallel technique rather than serial technique. The highest yields of crude extract by using both techniques were obtained with acetone, followed by water, ethanol, methanol, dichloromethane and hexane, respectively. Furthermore it was found that the L-a-b value and the total soluble solid (TSS) value in terms of degree Brix of crude extracts were different depending on choice of organic solvents. In particular, dichloromethane extracted more total soluble solid from plant material with both techniques, followed by hexane, ethanol, acetone, water and methanol, respectively. The biological activities of different crude extracts from S. tuberosa against Spodoptera exigua were experimentally determined. It was observed that the crude extract with highest toxicity to Larvae was obtained with high polarity solvents such as water, methanol and ethanol. The results suggested that water extract tested under high concentration could promote higher mortality. On the other hand, hexane extract caused approximately 30 % mortality with highest concentration at 15% w/w. Dichloromethane and acetone extract could be considered of similar efficiency.

Ever since the western corn rootworm (WCR) (Diabrotica virgifera virgifera), an alien invasive species from North America, has been introduced into Europe on at least 3 separate occasions, it spread within 15 years over the entire area of south-eastern and central Europe (except Denmark). Until quite recently, Zea mays L. was the only known host plant whereas in North America WCR also attacks members of the plant family Cucurbitaceae. In August of 2006, we were able to validate these findings also in the Old World by observing WCR visiting blossoms of oil pumpkin (Cucurbita pepo L.). Beside this first report of WCR on this regionally and economically important crop, a population increase in Gaberje near Lendava, Eastern Slovenia, was observed. Some future consequences of multiple hosts for integrated pest management (IPM) of WCR are being discussed.

Diabrotica v. virgifera (WCR) is one of the most successful invasive insect species and owes this success to its close association with mankind, to worldwide trade and commerce connections, and to widely practiced, monoculturally oriented production patterns which are characteristic for contemporary agriculture in several parts of the world. Without a drastic change in attitudes and approaches of a globalizing agriculture, WCR will in the foreseeable future have invaded all maize growing areas. WCR is continuing its spreading within Europe with its first documented appearance in Germany 2007, where two major and three minor sites of invasion are identified. Unfortunately, WCR already has secondary hosts and, through accelerated microevolution, soon may acquire more of them. The beetle may be seen as a clever follower in the footsteps of Homo sapiens and may thrive on worldwide ecological imbalances. Without major new paradigms in control and management approaches, WCR will be one of the big winners of globalization and mercilessly occupy the niches opening up. Some biotechnical and cultural alternatives are discussed which, in combination with biocontrol, may assist in evironmentally compatible management of WCR.

Monitoring of insects by trapping is one of the prime tools of field entomologists. The leaf beetle Diabrotica virgifera virgifera LeConte (Coleoptera:Chrysomelidae) is no exception. Since its numbers (and consequently its mass) in a field population can be enormous, tools must be adapted to hold this many insects for later counting, sexing, biomass determinations, and additional investigations to follow. Since counting the high numbers during the flight peak may not be feasible at all, weighing and extrapolating to numbers by the correlation factor 1g = 160 to 170 beetles of mixed female and male sex was the method of choice. Around the perimeter of a hybrid maize (Z. mays) field of 0.6 ha, 16 high capacity traps were established at elevations ranging from 0 to 2 m above ground level. Optimal trapping is possible between 0.5 to 2m which field entomologists intuitively knew from experience and tradition. Below and above that level, the number of beetles is not zero but significantly below the optimum. High capacity traps can be left in the field with one loading of lure for four to seven days. Lures were the D. v. virgifera beetle sex pheromone 8-methyl-decane-2-ol propanoate (0.1 mg, collecting mainly male beetles) and the plant kairomone 4-methoxy-trans-cinnamaldehyde (10 mg, collecting both male and female beetles). The specific kairomone action (being much weaker than the pheromone) can be increased by simultaneously offering a feeding arrestant powder (e.g. prepared from ground Cucurbita texana or C. okeechobeensis) which keeps the beetles attracted by the kairomone lure close to the trapping site. There they can be immobilized and knocked down by a tiny source of carbaryl or dichlorvos fixed inside or at the surface of a plastic pellet or sheet. The high capacity traps are commercially available and can be reused for several flight seasons.

The first invasion of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) into Slovenia was recorded in 2003. A few beetles were found in the western province of Slovenia near Italy. More beetles were detected in the eastern district of Prekmurje bordering Austria, Hungary and Croatia. While the western population remained the same in 2005, the eastern population increased considerably. By means of the very sensitive Metcalf sticky trap baited with the female sex pheromone, early infestations could be recorded. At corn fields, Zea mays L., near the villages of Dolina, Gornji Lakos and Pince, Diabrotica flights were observed in 2005 which had their maxima during the first week of August and yielded, respectively, 57, 112, and 45 beetles/trap per 3-4 day trapping interval. The increase from 2004 to 2005 in this eastern most district of Slovenia is noteworthy. Generally in the western and central part of Slovenia, most maize is grown in rotation, typically every second year. It is estimated that about 10 % of the surface of maize is grown as monoculture, typically on farms with intensive cattle production. In eastern Slovenia, a higher proportion of maize is grown in monoculture (about 30 % in the 3-year period from 2002-2004); this percentage decreased in 2005 due to official requirements by the Slovenian Phytosanitarian Administration.

The western corn rootworm Diabrotica v.virgifera (D.v.v.) (Coleoptera:Chrysomelidae) is endemic to the New World. On at least 3 occasions, it invaded Europe (Miller et al. 2005). The first of these invasions took place in or before 1992 (Baca 1993) to Belgrade, Serbia, and gave rise to a rapidly expanding beetle population in SE Europe. Its larvae are causing economic damage to Zea mays for the last ten years, with increasing severity both in acreage and density. Meanwhile Germany is still without proven infestations as of 2005, but is surrounded by countries invaded by D.v.v. It will be a matter of time and careful search efforts with efficient traps to detect D.v.v. on German territory as well. Three main terrestrial routes of future introduction are likely (Wudtke et al. 2005, Hummel et al. 2005 a and b; Baufeld and Enzian, 2005), one of them leading from Northern Italy through Southern and Northern Switzerland to Southwestern and Southern Germany.

The American Chrysomelid beetle Diabrotica virgifera virgifera LeConte (D.v.v.), also called the western corn rootworm, spread from the location of its original introduction into Europe, Belgrade airport (BACA 1993), in all directions. Within a decade it occupied almost all countries of South-eastern and Central Europe. However, it reached Slovenia as late as 2003: Only 19 specimen were found in maize fields of the eastern and also western provinces. Already in the summer of 2004, their number had risen to 386 which were mainly found in the eastern provinces near the borders to Croatia, Austria and Hungary. For their monitoring, a simple trap is being described which can be acquired in high numbers at a very low price and can guaranty a most sensitive detection of beetles. The Metcalf cup trap which in Slovenia so far has been unknown performed the task of monitoring quite well at five locations. It will also facilitate the future search for new and increasing infestations. Comparing 2004 with the year 2003, D.v.v. expanded its range in eastern Slovenia by about 15 km. These new infestations will include territories in which fields of the regionally Important oil seed pumpkin Cucurbita pepo are located. With important traffic connections between South-eastern and Central Europe, Slovenia will occupy a bridgehead function in the preventive protection of maize from D.v.v. spreading into more northerly European regions including western Austria and southern Germany.

Environmentally compatible and sustainable plant protection requires novel approaches to pest management characterized by minimal emphasis on toxicants. Classical toxicants traditionally dominated economic entomology for half a century. But worldwide problems with environmental pollution and with increasing resistance levels in all major pesticide classes and in many key insect species including Diabrotica virgifera virgifera (D.v.v.) strongly advocate a rethinking and a change in management paradigms used. Soft, minimally invasive, biological, biotechnical and cultural approaches should replace hard pesticides which are in favor up to now. Fortunately, pheromones, kairomones, plant attractants, better traps, new plant varieties and cultural methods like crop rotation, in short more sophisticated methods are now available as pressure for finding and exploring novel strategies increases. Facing this situation, a new biotechnical approach of population reduction of D.v.v., called "MSD" technique, is introduced. MSD is characterized as an approach combining mass trapping, shielding and deflecting of adult insects along an invisible odor barrier of synthetic kairomone which diminishes the flux of insects across a high capacity trap line baited with kairomone, thus reducing both the population fluctuation and number and its reproductive success within the shielded area. In the case of D.v.v. in Zea mays fields, effects realized by the MSD technique have been measured simultaneously by a number of independent criteria during the summers of 2003 and 2004 at 2 different locations in Illinois maize fields of up to one half hectare size. Results observed are statistically significant and cannot be explained by mass trapping alone. There is also an additional shielding and deflection, in short "diversion" effect whose basic sensory and behavioral mechanisms call for future exploration.

The western corn rootworm Diabrotica virgifera virgifera LeConte (Col.:Chrysomelidae) (D.v.v.) is one of the most important maize pests in North America. Ever since its invasion into Europe and its detection near Belgrade airport by BACA in 1993 it quickly spread all over southeastern Europe and is now advancing towards central Europe. Up until summer 2004 considered free of D.v.v., Germany is, with the exception of its northern and northeastern borders, surrounded by countries with proven D.v.v. infestations. In addition to simultaneous spot introductions by airplanes, three main routes for terrestrial introduction into Germany are likely: 1. from south to north via Lombardy (Italy) through Switzerland to the State of Baden-Wuerttemberg in the southwest; 2. from south east to northwest via Croatia, Slovenia, Austria into the State of Bavaria; and 3. from Belgium and the Netherlands in southeasterly direction to the state of Northrhine-Westfalia. From these, progress of D.v.v. along route 1 is so far the most advanced. It follows the well established network of road and rail connections through Switzerland and underscores the active role mankind and its technology plays as an active distribution vector for D.v.v. Mandatory crop rotation in the Swiss Canton of Ticino did slow down but could not prevent the northbound advance of D.v.v. in 2004. Considering the recent discovery of D.v.vu near the South German border, its introduction into German territory is only a matter of time and may be ecologically unavoidable. In Slovenla, another relatively small southern transit state, the D.v.v. population density is still much lower than in Switzerland but with significantly increasing trend during 2004 and with special emphasis in its southeastern provinces. Considering its relatively short distance to southeastern Bavaria and the well developed transalpine rail, road and tunnel system, Slovenia as a transit state may provide another access route for D.v.v. of lesser but still significant importance to Germany.

Serbia-Montenegro, formerly the Republic of Yugoslavia, is the first European Country where Diabrotica virgifera virgifera Le Conte (Col.: Chrysomelidae) (D.v.v.) was reported in 1992 as an invasive alien pest species, Baca (1993), Camprag and Baca, (1995): From a focal point near Belgrade airport, the maize pest quickly spread in all directions reaching the economic threshold in a number of surrounding countries around 1995. The field experiments described took place in the Banat region east of Belgrade in July of 2002. The plant kairomone mimic 4-methoxycinnamaldehyde (MCA) dissolved in acetone was slowly volatilized from paper squares. It permeated a maize field of known D.v.v. history of 0.5 ha size 3 km north of the village of Crepaja. With release rates of 266 g/ha, max. orientation disruption levels of 55% were achieved. The total amount of MCA was distributed in two manual applications. Readings of orientation levels were continued for eleven days during the latter part of July and into early August of 2002.

The late Professor R.L. Metcalf is being honored as one of the leading entomologists of the 20th century, whose worldwide influence on entomology, insecticide and environmental toxicology, and insect chemical ecology was enormous. His 82-year life span mirrored the transition in entomology from the early descriptive phase of insect and plant and animal interactions to the more detailed integration of the biochemical, physiological, behavioral, ecological, and environmental understanding of nature within the context of societal issues and needs. New techniques, some relatively simple but never-the-less ingenious, paved his way to fame. Metcalf was an enormously productive scientist. His 450+ research publications, numerous books and editorships, patents, internationally oriented staff of students, postdocs and associates, and his contributions to teaching and to public service let him stand out as a challenging role model for those young minds starting their careers at the beginning of the 21st century.

Field studies in corn (Zea mays L.) were conducted to evaluate distribution patterns of 4-methoxy-cinnamaldehyde (MCA) coated corn grits after aerial application with a Dromader fixed wing aircraft. The kairomone mimic MCA is synthetically available and a quite specific and efficient adult attractant for the invasive alien maize pest western corn rootworm (WCR) Diabrotica virgifera virgifera LeConte. Orientation disruptive properties of MCA for WCR when applied at unphysiologically high concentrations are currently under investigation. For successful implementation of the MCA disruption technique, the distribution patterns of MCA coated corn granules ('grits') in the field are important. Grits are degrained corn cobs, shredded to different sizes, coated with MCA and used as a carrier material to disseminate MCA vapors into corn fields. Granules of 10-12 mesh size were aerially applied eight times at rates ranging from 12.4 to 25.0 kg/ha. The goal is to evaluate distribution patterns of corn grits treated with MCA in three fields located at Csanadpalota, Kardoskút and Mezöhegyes in Southern Hungary between 2000 and 2002. Increasing rates reflect our attempts in finding and optimising the most even distribution of granules in the field. Field experiments were evaluated by collecting grits in 30-cm plastic saucers and by counting grits accumulated on corn plant parts. Variation in grit number per unit area and frequency of corn granule number per plant showed some transient technical application problems. Analysis of grits collected in the saucers revealed some statistical difference between the different application dates as well as differences in rates applied. Altogether grits in saucers were more evenly distributed in comparison to the grits collected on plant parts. As the corn plants age, their leaves and whorls present a smaller and smaller surface area where granules can accumulate. Altogether, however, grit distribution patterns indicate that aerial application is a viable tool for disseminating MCA in corn fields.

Maize growers repeatedly are confronted with the need to make predictions and decisions about which of their fields are likely to develop corn rootworm populations above the economic threshold and are in need of treatment. One of the best parameters that can help as a basis for these decisions are corn rootworm egg counts in the soil. The Western corn rootworms have one generation each year. Females oviposit eggs in the soil in corn fields from late July through early September. These eggs overwinter in the soil and almost all hatch the following June. An apparatus is described that utilizes water, MgSO4 solution and differing screen sieves for extracting the rootworm eggs from the soil samples collected from the field after deciding on an acceptable sampling procedure. Samples may be a composite of subsamples or a number of individual samples taken at various locations in a field. The Illinois machine and the final separation of eggs, using flotation in 2 molar MgSO4 solution, are highly efficient, and recoveries of 97% of rootworm eggs manually placed in samples of soil have repeatedly been achieved. Thus, this would be a useful tool in integrated pest management programs that monitor the density of corn rootworm eggs in corn fields.

Diabrotica v. virgifera LeConte (Coleoptera: Chrysomelidae), (in short D.v.v.), with common name western corn rootworm, is endemic to the New World. Originating in the regions from South America to Mexico where it was in biological equilibrium with its natural enemies, predators and pathogens, it moved north with its food plants. Probably due to human agricultural farm practices with preference for monoculture of maize, the insect found open niches for expanding to the midwestern US where LeConte first described the species in Nebraska in 1867. Cyclodiene insecticide resistance, discovered in 1961, accelerated its spread and movement across the Great Plaines to the Atlantic Coast where it arrived around 1980. D.v.v. is a costly adversary to maize, to cucurbit, and, because of recent hostshifts, a threat to soybean production. Booming air travel and shipments of goods by air provided opportunities for D.v.v., without its natural enemies, to invade Europe where the insect was first described by F. Baca in 1993 near Belgrade airport (Baca 1993, Camprag & Baca 1995). From this focal point, D.v.v. expanded its range in all directions. Ten years later, in 2002, most of southeastern Europe has D.v.v. populations, some of them reaching economic damage levels such as those in Serbia, Croatia, and Hungary. New spot infestations in Northern Italy (Veneto, Lombardy, Piemonte) and in the Ticino region of Southern Switzerland, but also in Austria, Slovakia, Czechia, the Ukraine, even France, signal the final arrival of D.v.v. in Central Europe. The Alps, formerlyconsidered a natural barrier, might be circumvented or trespassed via air and road traffic. Model calculations by Baufeld and Enzian (2003) show that climatic and survival conditions are favorable for D.v.v. in all of Central Europe. Yet, in spite of well known annual losses of one billion dollars in the US, an effective and sustainable European strategy for keeping D.v.v. in check is still missing.

A trap is described that uses as a simple natural ingredient a cucurbitacin mixture to capture and carbaryl insecticide to kill northern and western corn rootworm beetles (Diabrotica barberi Smith and Lawrence, and Diabrotica virgifera virgifera LeConte (D.v.v.), respectively). The trap is consistent in numbers of beetles captured per trap per day, and it should be useful in integrated pest management programs to monitor the population density of rootworm beetles in corn fields. Captures between 1981 and 1983 in Illinois showed that western corn rootworm adults that disperse into first-year cornfields were predominantly females. These traps are being utilized today (2003) by many researchers in the New World desiring to know more about rootworm beetle movement and activities. Entomologists in the Old World confronted with the alien invasive pest D.v.v. should profit likewise from increased knowledge and availability of these traps for Diabrotica management.

Field studies in corn (Zea mays L.) were conducted during the summer of 2000 to evaluate distribution patterns of corn grits treated with MCA (4-methoxy cinnamaldehyde). Aerial application was used in a 8 ha corn field situated in south-east Hungary. Corn granules ('grits') of 10-12 mesh size were applied on July 18th, August 1st and August 28th at rates of 18.3, 21.9 and 20.2 kg grits/ha and were covered with 80, 119 and 120 g MCA/ha. Experiments were evaluated by collecting grits in 30-cm plastic saucers and by counting grits accumulated on leaves and in leaf axils on corn plants. Analysis revealed a statistical difference between MCA treated and untreated grit application rates only at the first application date. Variation in grit number per unit area and frequency of corn granule number per plant showed some transient technical application problems. However, altogether, grit distribution patterns indicate that aerial application is a viable tool for disseminating MCA in corn fields. With it, orientation disruption of the introduced maize pest Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) recently introduced into SE Europe will come within reach.

An electroantennographic detector based on the antenna of the Colorado potato beetle (Leptinotarsa decemlineata Say, 1824) was used to investigate volatile organic compounds emitted by injured potato plants (Solanum tuberosum L., 1753). Samples were collected on charcoal traps using the CLSA method. Analyses were performed with a GC-EAD-FID setup as well as a GC-MS system. The experiments revealed that several groups of compounds are perceptible to the Colorado potato beetle. The ability of the Colorado potato beetle to detect green leaf odours (e.g. (Z)-3-hexen-1-ol and (E)-2-hexenal), linalool and some terpenes has been noticed before [Visser et al., J. Chem. Ecol. 5 (1979) 13]. In this work the presence of (Z)-3-hexen-1-ol, (E)-2-hexenal and linalool in the potato odour could be confirmed. Moreover, beta-myrcene, benzeneethanol, and several sesquiterpenes (e.g. caryophyllene and germacrene-D) were identified. The GC-EAD experiments reveal that apart from the green leaf odours and linalool prominent reactions of the Colorado bettle antenna are induced by benzeneethanol and the sesquiterpene fraction.