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• Examination of nitrogenous compounds in Hungarian bio-musts

  109-113.

  M. Kállay

  D. Nyitrainé Sárdy

  Views:

  456

  There has not been any research done on the musts from organic grapes. As a result of the special technologies in organic farming we can expect bio-musts to have a different quantitative and qualitative composition of nitrogen compounds from that of traditional musts. In our present essay we deal with the tests of nitrogenous compounds (assimilable nitrogen content, aminoacid, biogenic amine content) in musts from Hungary's bio-wine cellars. Our results show that the change in procedures has resulted in neither quantitative nor qualitative changes in the nitrogenous compounds of bio-musts.

• Field Vegetable Production in Hungary

  81-84.

  E. Kristóf

  I. Terbe

  Views:

  414

  Hungary is a country with excellent ecological potentials and with rich traditions in vegetable production. The total vegetable production area comprises about 100 000 ha and annual production amounts to 1.4-1.8 million tons, 75-80% comes from fields and the rest from forcing. Approximately 40 species are produced, but only 20 of them play a dominant role. The most important ones arc: sweet corn, peas, peppers, watermelon, onions, tomatoes, gherkin, carrots, beans, white cabbage.

  40-45% of the total production is processed, 20-30% sold on the fresh market and 30% exported.

  Vegetable production is based on rural farms of 1-5 ha average acreage. It provides living for about 70-100 000 families. The low number of producers' organisations is a major setback.

  Profitability of vegetable production is rather low. Production costs are high, wholesale prices are depressed.

  Vegetables are produced for the industry by contract. Fresh vegetables are sold through local markets (15-20%), the wholesale market (decreasing importance) and direct marketing (35-40%).

  Against the self-sufficiency of the country there is a seasonal import of vegetables mainly in winter and early springtime.

  Hungarian legal regulations are harmonized with the EU directives, EU standards are accepted and applied, traditionally good market connections and cooperation with several EU countries enable the country to be a partner of EU vegetable growers.

• The comparative economic analysis of Hungarian and German apple production of good standard

  79-85.

  F. Apáti

  Views:

  549

  The profitability of the Hungarian apple production considering firms producing on high standard is not lagged behind significantly from that of German firms, moreover in certain cases it reflects a more positive situation. It is unfavourable, however, that this statement is true only for 8 to 10% of our whole apple plantation surface. The results of the investigations highlighted the fact that in comparison with Germany our farm business advantages manifest in three factors: in 70 to 80% lower wages, in 15 to 30% higher investment and subsidy intensity and in the fact that at present we cannot neglect the ice safety system which is rather expensive. By the increasing wages, the narrowing subsidy opportunities and incidentally the appearing harmful weather phenomenon, these advantages may be continuously ceased. Our definite disadvantage appears in the level of marketing price, considering the fact that producers in Hungary realize 30 to 35% lower marketing price, which is in connection with the probably much lower level of organization among farmers, in the market and in the logistical background.

• Comparison of Xanthomonas arboricola pv. juglandis isolates from walnut trees grown in Romania and Hungary

  65-69.

  A. Bandi

  Views:

  446

  Among diseases that affect walnut, bacterial blight is considered the most important one in all walnut growing areas both from Hungary and Romania. For the determination of susceptibility/resistance of walnut cultivars in our posterior work planned, 61 bacterial isolates were collected from walnuts showing symptoms of blight, with the purpose of isolating Xanthomonas arboricola pv. juglandis (Xaj). The characteristic Xaj colonies, frequently present as saprophytes in the infected plant tissues, were separated from other bacteria according to their morphology, yellow colour, hydrolysis of starch, and oxidation of glucose. All isolates were tested for pathogenicity by hypersensitive reaction on tobacco leaves (Nicotiana tabacum L.), bean pods (Phaseolus vulgaris L) and unripe nuts (Juglans regia L.). Determination of taxonomy of the selected isolates denotes a possible subdivision (races, biotypes) of Xaj occurring in different geographical areas, API 20NE and API 50CH kits were used. Hungarian and Romanian strains showed a high degree of similarity of carbohydrate utilization but slightly differed from the type strain. All were Cu-sensitive.

• The development and reproduction of grape phylloxera (Daktulosphaira vitifoliae Fitch) strains of Hungarian vine-districts in root-bioassays

  67-71.

  H. L. Tóth

  L. Horváthné Baracsi

  L. Kocsis

  Views:

  253

  The root bioassay method allows for 4-6 week continuous observation of grape phylloxera feeding on the grape root. 10 Hungarian phylloxera strains were compared on susceptible Vitis vinifera cv. Chardonnay and the resistant rootstocks of V. berlandieri x V. riparia Teleki 5C and V. berlandieri x V. rupestris Georgikon 121 in in vitro observations. The strains originated from Villany and Eger (Figure 3) had higher reproduction on the root of V. berlandieri x V. riparia Teleki 5C (201 and 119 eggs) and were more aggressive than the others (average production 10 eggs). The continuous high level of survival, development and reproduction of the Eger strain on Teleki 5C (V. berlandieri x V. ripuria) until day 46 may be due to adaptation.

• Economic figures of sour cherry production at national level of Hungary

  107-109.

  J. Felföldi

  Views:

  373

  After the political changes of 1989, economical processes impaired heavily the Hungarian fruit growing branch, more particularly production of sour cherry. Paralleling with the increasing mass of production, producer’s prices dwindled drastically. At present, Hungarian growers cannot cover the costs of production, nay, hardly raise income. My purpose was to analyse the cost and income relations of the sour cherry branch during the period of 2002-2009 years in order to find out what are the decisive features, which reveal the trends to be considered. The data presented in the paper are means of a heterogeneous population of values, which cannot be utilised for immediate use in management, but they may reveal the challenges and tendencies of economics of the branch.

• Greeting of Sándor Balázs, Member of the Hungarian Academy of Science on the occasion of his 80th birthday

  7-8.

  F. Zatykó

  Views:

  189

  Greeting of Sándor Balázs, Member of the Hungarian Academy of Science on the occasion of his 80^th birthday

• The necessity and possibilities of irrigation in fruit growing under conditions of Hungary

  93-94.

  J. Kovács

  J. Nyéki

  Z. Szabó

  F. Ligetvári

  M. Soltész

  Views:

  771

  Climatic and soil conditions are highly suitable for most temperate fruit species and promise profitable yields with good quality. An accurate choice of the growing site is, however, decisive because of the wide range agro-climatic variation an soils within the country. One of the most important factors is the annual precipitation which does not exceed, in general, 700 mm. The aims of irrigation practices are, succinctly speaking, the improvement of quantity and security of yields and the guarantee of quality. The relative importance of those criteria changes according to the fruit species. In up to date apple, pear and cherry production, micro-irrigation systems are mainly considered. According to recent experiences, the micro-jet type of water distribution should be preferred to the dripping system. In cherries, the choice of the method is motivated by the need to prevent fruit cracking. Most of the peach and apricot plantations are located on the dry and moderately dry regions of the country. Because of the late freezes, the improvement of security is crucial. There the investment of irrigation systems should concentrate to the possibility of anti-freeze sprays. High water requirements of plums are met in Hungary by irrigation where the method should be decided at the plantation and adapted to the harvesting procedure which could be mechanised or (in high density plantations) picked by hand. Sour cherries are perhaps the less dependent on watering under Hungarian conditions. Yields in small fruits: currents, gooseberries, raspberries and strawberries could be increased by irrigation to 40-50 % and may improve quality too. In those cultures the system of moving flexible wing tubes are considered to be the best irrigation technique.

• Fruit drying traditions in Hungary

  7-10.

  D. Surányi

  Views:

  623

  Since the early eras of human history, the gathered products (roots, shoots, crops, fruits etc.), the environmental conditions of the preservation of the animals caught and the fishes; and accidental observations have been born new methods. Under cold and moderate climates, the effect of permanent frost, the use of ice as a means of curing as in dry, desert areas is the drying or exsiccation and the dehydration of salt. For convenience reasons, some of these methods have been forgotten, but the resurfacing of different fruits seems to resume. The short review gives an overview of the methods of drying used in the Carpathian Basin, especially among the Hungarian ethnic groups, which by the Hungarian ethnology thoroughly explored. The author attaches outstanding importance to the fruit-drying industry, because dried-ups at industrial scale are not equivalent to traditional low-fat lime scales. Excellent drying products are much better in terms of eating habits, with modern methods and small-scale production relatively easy to produce.

• Exploring and preserving old apple cultivars of the Carpathian basin

  9-13.

  M. Tóth

  Views:

  318

  In a few scattered orchards of the Carpathian basin one can still find our most common historical apple cultivars and certain traces of traditional cultivation. We consider it an important part of the Department's breeding work to explore old apple cultivars which can be used as parent partners and sources of resistance, to identify them pomologically as well as to examine the production and marketing value of old cultivars recommended for cultivation in ecological production and in gardens. This paper documents the results of expedition and collecting work carried out in three regions of the Carpathian basin (foot of the Carpathian Mountains, Transylvania, Aggtelek karst area), and also the saving of old Hungarian apple cultivars preserved until present in the English National Fruit Collection. A total of more than 100 old apple cultivars and variations, as well as 13 valuable genotypes were collected during our explorations in the above mentioned four areas. A further aim of our work is to contribute to the protection of still savable archaic fruit production relict= areas and to the preservation of cultivars in the certain regions, and also to promote the recognition of the aesthetic landscape value of old apple trees and endemic orchards of old cultivars. Our good co-operating partners in this work are Aggtelek National Park, Farmer Club of Visk and the consultation centre of Hungarian horticulturist training beyond the border in Nyárádszereda.

• The hungarian raspberry today and outlooks of its development (Review)

  7-11.

  J. Z. Papp

  L. Kiss

  J. Nyéki

  Views:

  784

  The hungarian raspberry today and outlooks of its development (Review)

• Old Hungarian grapevine cultivars and their relations characterized with microsatellite markers

  27-31.

  P. Bodor

  Zs. Varga

  T. Deák

  A. Pedryc

  Gy. D. Bisztray

  Views:

  508

  Thirty-one old Hungarian grapevine (Vitis vinifera L.) cultivars were investigated on 7 microsatellite loci to characterize them, to separate the cultivars from synonym names, and to confirm parent-offspring connections. Conculta (group of cultivars or bud sports) members, such as `Goher' and Tajor' representatives, were studied to find a suitable locus for the separation. Synonyms, conculta members, subcultivars and clones of Turmine, which was the most important cultivar of Tokaj, were also analyzed to separate the members of the different taxonomic levels. Pedigree of 'Kiralyleanyka' was examined to find the missing ancestor, because the parent-offspring connection between the natural hybrid and `Koverszolo' is questionable.

• Virus susceptibility and resistance of Hungarian pepper varieties

  68-73.

  J. Horváth

  G. Kazinczi

  A. Takács

  D. Pribék

  G. Bese

  R. Gáborjányi

  Kadlicskó S.

  Views:

  306

  The aim of our study was to examine susceptibility or resistance of 18 pepper varieties to four viruses [tobacco mosaic

  tobamovirus (TMV), sowbane mosaic sobemovirus (SoMV), NTN strain of potato Y potyvirus  (PVYNTN) and cucumber mosaic cucumovirus (CMV). Out of the 18 varieties, 13 were resistant to CMV infection. Thirteen varieties were susceptible to TMV, while five ones (Dabora Fl, Brill Fl, Feherozon Synthetic, Ciklon Fl, Cecil Fl) showed only local hypersensitive reaction. All of the tested pepper varieties showed resistance to SoMV. Eight varieties (Tuba, Fehérözön Synthetic, Boni, Alba Regia, Korona, Édesalma, Cecil Fl, Star) were found to be resistant to PVY^NTN. Out of the examined varieties five (Boni, Alba Regia, Korona, Édesalma, Star) were resistant to three viruses (SoMV, CMV and PVYNTN). Only one (Cecil F1) displayed complex, extreme resistance to SoMV, PVYNTN, CMV and hypersensitive reaction to TMV, therefore this hybrid is very important in pepper breeding and growing for virus resistance.

• Farm economic evaluation of raspberry production

  53-56.

  F. Apáti

  Views:

  634

  Hungary was considered as one of the most significant raspberry producers in the 1980’ies. The acreage and the produced quantity, however, reflected a decreasing tendency during the past two decades: the 7 000 hectares existing in the year of 1990 reduced to 1 500 hectares, the current territory does not reach the 500 hectares. The annual yield is only 1 to 3 thousand tons. The level of domestic fresh consumption is very low, due to the fact that it is a relatively expensive fruit for Hungarian consumers. The requirement of the processing industry is satisfied by raspberries from mainly Polish and Serbian import. These two countries belong to the biggest raspberry producing countries in the world by producing raspberries of more than 50 thousand tons. Comparing to the Hungarian production costs and yields they are able to transport their products here at a very low price, consequently they hold the prices at a low level. The profitability of the domestic raspberry production is rather unfavourable, production often shows a deficit even in orchards of good standard; furthermore the lack of labour causes an extremely great difficulty, which is an important component of the decline of the production independently from cost conditions.

• Association of varieties in stone fruit plantations

  29-33.

  J. Nyéki

  Z. Szabó

  M. Soltész

  Views:

  789

  In the majority of Hungarian orchards of stone fruits, the planting distance is 6-7 m x 4-5 m. As many of the current varieties are self-incompatible, planting designs are applied to provide for adequate pollinisers. As long as differences in blooming time are small, i.e. 3-5 days at most, overlaps of blooming of the associated varieties are sufficient for fruit set.

  In sour cherry, one leading variety, Pándy, is self-incompatible and requires two polliniser varieties at least (Ciganyneggy or some sweet cherry varieties). Pándy is, moreover, cross-incompatible with the varieties Debreceni bőtermő, Kántorjánosi and Újfehértói fürtös being all of them self-fertile as most of new varieties recommended, by the way, for being planted to monovarietal blocks.

  Among European plums there are varieties registered as male sterile, self-incompatible, parially self-fertile and self-fertile, respectively. For the purpose of cross pollination, the choice of two varieties, at least, to be associated to any variety belonging to the first three groups, is recommended. The number of rows in blocks planted to self incompatible or male-sterile varieties should not be higher than 2-(4). Inter-incompatibility has been observed within the currently recommended assortment, between the varieties Cacanska najbolja and Stanley, only. Chinese-Japanese plums are scarcely represented in Hungarian plantations. Variation of blooming time in varieties is somewhat more pronounced, i.e. 5-8 days. There is but a weak tendency to self-fertility, thus practically, all varieties are considered as self-incompatible, thus the planting of two-row blocks for each of three varieties, at least, are recommended to be associated.

  Self-incompatibility and partially self-fertile apricot varieties are recommended to be combined with two polliniser varieties, at least, each planted to two-row blocks. The varieties Ceglédi óriás, Ligeti óriás, Nagykőrösi óriás and Szegedi Mammut are mutually inter-incompatible. Most of the peach varieties grown in Hungary are self-fertile, thus they are planted to large blocks, each. On sites threatened by late spring frost, it is recommended to plant (monovarietal) blocks of 4-6 rows at most. Cross-pollination may increase fruit set even in self-fertile varieties.

   

• Investment analysis of Hungarian apple-orchard and fruit storage projects

  157-162.

  F. Apáti

  Z. Lakner

  Views:

  598

  There are profound, long-term changes in world apple production and trade. The former hegemony of Europe in apple production doest not exists any more, among the most important apple exporters the emerging economies have a growing importance. The globalising apple market means new challenges of traditional producers. This is especially true for Hungary, which has been the most important apple exporter in terms of quantity thirty years ago, but now its production hardly covers the domestic demand. A necessary precondition of the modernisation is the re-construction of plantations and the cold-storage system. Analysing the economic effi ciency of apple production and cold storage, it is obvious, that a necessary precondition for the modern, competitive apple production is the availability of cold-storage facilities. Neither the apple-production, nor the cold-storage can not evaluated separately from each other. Under current Hungarian conditions there is a need for active state support for the establishment of cold-storage facilities.

• Flower microphenology of Hungarian sour cherry cultivars in Iran climatical conditions

  99-101.

  H. G. Davarynejad

  Z. Szabó

  J. Nyéki

  M. Ansari

  Views:

  1080

  Determination of flower microphenology for selecting the suitable pollinizer for sour cherry cultivars is of significant importance. In order to study the flower microphenology of Hungarian sour cherry (Bőtermő, Érdi jubileum and Cigány) cultivars in Mashhad climatic conditions, an experiment was conducted in I998. 1999, 2005 and 2006, using a completely randomized design with ten replications. The phenological stages were determined from before opening up to browning phase of stigma. Duration of pollen shedding, stigma receptivity and climatic factors were measured. The relative time of flowering between cultivars varied from year to year. The data indicate, the thermal variation strongly contributes to significant differences in duration of stigma viability, although there wasn't a significant difference between cultivars in anther dehiscence period. Phenological stages of flowers are highly affected by meteorological factors in various years.

• Comparative analysis of the production risk of major fruit species

  119-122.

  Sz. Persely

  Views:

  311

  Hungary possesses excellent agri-ecological potentials even in an international comparison. Despite their decreasing economic weight, agriculture and food production are of great significance, since the supply of the population with high quality and inexpensive food is a fundamental social demand and one of the essentials of the quality of life. The development of vegetable and food production is of great importance both from the aspect of healthy nutrition and comparative advantages (cheap workforce, professional expertise, traditions of production, climate favourable for quality). Within the Hungarian fruit production apple and sour cherry are essential branches in virtue of their significance. It is widely known, that – though to a different extent in the case of certain fruit varieties – satisfaction of the need for appropriate habitat is one of the important conditions of a decent quality and secure production. In my research, I analyse the territorial distribution, production standard and production risk of the Hungarian apple and sour cherry branches. I did not have the opportunity – because of the imperfections of the database – to compare long time series, therefore I examine the random effects affecting production by using the data of 3 years (they have the same content). I ranked and assessed each habitat and the production risks of certain fruit species compared to each other on the basis of indexes of relative deviation.

• Fruit production and research in Hungary - An overview

  7-11.

  J. Papp

  J. Nyéki

  M. Soltész

  Views:

  1241

  Hungary is traditionally a food producer country. 63% of its total land area can be cultivated. Horticulture is one of the fundamental agricultural branches. The country has a moderate continental climate, with a mean temperature of 10 °C. The average hours of sunshine ranges 1,700 to 2,100 hours. Under the geographical condition in the Carpathian Basin the chemical composition of the fruits has a good harmony. The total fruit acreage is 97,000 ha with a crop of 800,000 to 900,000 tons yearly. In 1982 1,934,000 tons of fruit crop were produced since then it has decreased. The most important fruits are apple, European plum, sour cherry and raspberry. The percentage of apple reaches almost up to 60%. In the new plantings sour cherry, apple and black elderberry is popular. The most important fruit-producing region is situated at the North-eastern part of the country. More than 40% of Hungary's fruit production is concentrated there. In ranking the 2^nd place is taken by fruit growing area in the middle of Hungary, where the production of stone fruits and small fruits has a considerable proportion.

  In the 70s and 80s of last century there was a developed research structure and wide range of research activity in Hungary. From that time the research capacity has considerably decreased first of all in the field of technological development. The main research area is fruit breeding and variety evaluation.

  Fruit scientists and fruit grower specialists are held together by the Hungarian. Society for Horticultural Sciences which has a membership in ISHS. Fruit researches and scientists having academic degree are belonged to the Horticultural Board of Hungarian Academy of Sciences.

• Xanthomonas resistance in Hungarian 4 spice pepper varieties

  73-77.

  F. Márkus

  J. Kapitány

  G. Csilléry

  J. Szarka

  Views:

  299

  With a view to further enhance the reputation of Hungarian spice pepper it was necessary to improve resistance to the bacterium Xanthomonas campestris pv.vesicatoria, the most dangerous pathogen of pepper varieties. From among the familiar resistance genes in Hungary only the gene Bs-2 could provide sufficient protection against the aggressiveness spectrum of the bacterium species X.c.pv. vesicatoria. The first results of the resistance breeding are the spice pepper varieties Kaldom and Kalorez. In addition to the Bs-2 gene attempts are also being made at building in a gds gene into pepper, a gene creating a general defense system, a different strategy towards Xanthomonas campestris pv. vesicatoria.

   

• Testing the virulence of some Hungarian Erwinia amylovora strains on in vitro cultured apple rootstocks

  52-55.

  M. Hevesi

  J. Papp

  E. Jámbor-Benczúr

  K. Kaszáné Csizmár

  I. Pozsgai

  Gy. Gazdag

  I. Balla

  Views:

  535

  A useful method was improved to test and to evaluate the susceptibility of plants to fire blight and the virulence of E. amylovora strains. Six Hungarian strains from different host plants were tested on in vitro cultured apple rootstocks. Disease rating was used for the characterization of the process of disease development. The different strains had different capacity to cause disease, mainly in the first period of incubation. There were significant differences between the virulence of the strains.

• The Hungarian pear germplasm as source of genetic variability for breeding programmes

  7-13.

  T. Szabó

  I. F. Labuschagne

  S. Musacchi

  J. Nyéki

  J. Tornyai

  M. Soltész

  Z. Szabó

  Views:

  805

  TheHungarian pear collection (Pyrus communis L.) consists of 423 genotypes distributed over seven genebanks inHungary. This is one of themost extensive collections of native and cultivated pears found in Eastern Europe and includes a wide range of genotypes with small size fruit (referred to as “Miniature pears”). Based on the in situ and ex situ measures taken by governmental and other institutions for fruit tree conservation in Hungary, an overview is given on some activities regarding areas of Pyrus collection and genebanks where pears are collected and grown. Descriptions of traits of miniature pears found in Hungarian genebanks for the interest of genetic characterization and breeding are presented.

• Selection of the chance seedlings of `Mézes körte' (Pyrus communis L.) from the gene bank of Keszthely

  21-27.

  J. Varga

  J. Iváncsics

  G. Kocsisné Molnár

  J. Nyéki

  Views:

  719

  We have concluded the selection tests of the `Mézes körte' seedlings planted in the spring of 2006, with special emphasis on the cotyledonary, foliage leaf and the height of plant. Out of the 75 seeds planted in rows, there were 40-45 pieces growing out, so during the first cotyledonary test we had to calculate with almost 40% decay. On 12th April 2006, we recorded some of the important characteristics of the seedlings in their cotyledonary stage which characteristics were important from the point of view of selection (cotyledonary form, cotyledonary length, cotyledonary thickness, cotyledonary colour, cotyledonary petiole length, cotyledonary petiole thickness, cotyledonary petiole colour). The above morphological characteristics are shown in Table No. 1-6. We have also tested the seedling in foliage leaf state, paying special attention on the development stage of the plants (colour of foliage leaf , height of plant). We have completed statistical calculations of the two above mentioned characteristics. The result of that is summarised in Table No. 8-9. The variation coefficient show smaller value in the case of the foliage leaf number (15-32%), while the wider range of spread of the data referring to the height of the plant is shown by the 33-61% CV values. On charts No 4-9. we present the relationship between the height of the plant and the number of foliage leaf, as well as the differences between the two graphs. Based on the above charts and graphs it can be defined that the 40% destruction of the developing seedlings during the period till the next measurement reached 70-80% level. In spite of this however some seedlings showed strong and balanced growth (A₄₄, B₄₂, C₂₅, D₁₆, E₅, E₃₉, F₃₈), the further testing and selection of those is to be completed in the future.

• Microsporogenesis of peach (Prunus persica L. Batsch) varieties

  7-10.

  L. Szalay

  B. Timon

  Z. Szabó

  J. Papp

  Views:

  1068

  Bud dormancy during winter is a critical factor in peach production in Hungary. The yield is determined basically by the survival rate of flower buds during winter frosts and by their ability to develop normal floral organs. It is important to investigate the genetic basis of slow floral development during dormancy for the purpose of breeding peach varieties with better winter hardiness. The aim of the present research was to examine microsporogenesis in 14 peach varieties during three successive winters in a Hungarian germplasm collection and to study the effectiveness of this method in variety evaluation. There were significant differences in the dynamics of microsporogenesis both between the varieties and between the years. Of the varieties, ‘Mayfire', bred in California, possessed the quickest pollen development rate. The microsporogenesis of `Piroska', a Hungarian local variety, was the slowest. Rapid floral bud development was observed in `Aranycsillag', `Springcrest' and 'Venus'. A medium developmental rate was characteristic of `Babygold 6', Fairlane', `Michelini' and `Red June', while development was slow in 'Champion', 'Early Redhaven', `Redhaven', `Harko' and `Mariska'. Based on these results, the study of microsporogenesis represents a reliable method for the phenological description of peach varieties during dormancy. The application of this method makes it possible to identify varieties and landraces with slow flower bud development, suggesting better winter hardiness.

• Chemical communication with volatile semiochemicals in Phyllotreta species (Coleoptera, Chrysomelidae): a minireview

  93-100.

  É. Csonka

  M. Tóth

  Views:

  555

  Phyllotreta species (Coleoptera, Chrysomelidae, Halticinae) rank among the most important horticultural pests in the Northern Hemisphere. Leaf damage caused by flea beetles upsets the water balance, blocks plant growth and sometimes causes a high level of mortality of seedlings. Several species are known to act as vectors of numerous pathogens as well. Chemical communication plays an important role in the host finding, feeding and oviposition behaviour of flea beetles. In the first phase volatile mustard oils (isothiocyanates and thiocyanates) are released from the host plants through the decomposition of non-volatile glucosinolates (chemicals specific to Cruciferae) by myrosinase, and beetles are attracted to the source of release from a distance. Among the isothiocyanates, allyl isothiocyanate is the longest known and widespread compound utilized in the host-plant location of Phyllotreta species, but some species may have a stronger preference to other isothiocyanates or thiocyanates. The attractive effect of the plant volatiles is enhanced by the emission of a male-produced aggregation pheromone. The presence of such a pheromone was first demonstrated in Phyllotreta cruciferae Goeze. In this species R5R,5aS)-1,1,5,8-tetramethy1-1,2,3,4,5,6,5a-heptahydrobenzo[1,2-a][7]annulene] was found to be the main pheromone component. Significant attraction by the pheromone was recorded only in the presence of ALLYL ITCN. The biological activity of the pheromone compound was connected to the plus (+) chirality. The same component seems to be occurring also in the pheromones of several other Phyllotreta spp. as well, suggesting a wider occurence in the genus. Once attracted by the joint effect of plant volatiles and aggregation pheromone, the presence of the non-volatile glucosinolates in the plant tissues is necessary for continuous feeding. Aggregations of flea beetles on suitable host plants, which result from the joint effects of plant-derived and pheromonal chemical cues detailed above may also be good rendez-vous occasions, increasing the probability of encounters with the opposite sex and mating in the vicinity of the optimal oviposition site. Due to the horticultural importance of Phyllotreta spp., deciphering details of their chemical communication has considerable significance in the development of new methods of integrated control.