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  • Phytoplasma diseases on fruits in Hungary
    24-29
    Views:
    157

    In the last twenty years, three phytoplasma diseases were identified in Hungary, viz. European Stone Fruit Yellows (ESFY) (caused by Candidatus Phytoplasma prunorum), pear decline (caused by Candidatus Phytoplasma pyri), and apple proliferation (caused by Candidatus Phytoplasma mali). Candidatus Phytoplasma prunorum was isolated from apricot, peach, plum and japanese plum. Cacopsylla pruni the vector of ESFY was also isolated and identified. Infection of Candidatus Phytoplasma pyri was diagnosed from pear and Candidatus Phytoplasma mali was found on apple and pear. The three phytoplasmas cause different damages on their host plants. The most economically important phytoplasma disease is the ESFY. It seriously impairs apricot and japanase plum trees. After infection of apricots and japanese plums show yellowing and defoliation, and within a few years die in apoplexy-like symptoms. The disease on japanese plum is so severe that this fruit practically can not be cultivated in Hungary. Pear decline is the most serious problem especially in intensive pear plantations. The vector Cacopsylla pyri, C. pyrisuga and C. pyricola can be found in almost all pear orchards. Because of the regular presence of psyllids in intensive pear orchards the insecticide control is necessary. Apple proliferation is not an important disease in Hungary. All of our isolations of ’Candidatus Phytoplasma mali’ occured in organic orchards and record was not available in Hungary lately.

  • Dieback of apricot plantations caused by 'Ca. Phytoplasma prunorum' in Borsod-Abaúj-Zemplén county (Northern-Hungary)
    34-41
    Views:
    105

    Plant diseases caused by phytoplasmas have increasing importance in all over the world for fruit growers. Lately, phytoplasma diseases occur on many fruit varieties and responsible for serious losses both in quality and quantity of fruit production. In the long-run these diseases cause destruction of fruit trees. The apricot phytoplasma disease (Ca. Phytoplasma prunorum) was first reported in Europe in 1924 from France. In 1992 the disease has also been identified in Hungary. On the base of growers' signals serious damages of "Candidatus Phytoplasma prunorum" Seemüller and Schneider, 2004 (formerly: European stone fruit yellows phytoplasma) could be observed in different stone fruit plantations in the famous apricot-growing area nearby Gönc town, Northern-Hungary. Field examinations have been begun in 2009 in several stone fruit plantations in Borsod-Abaúj-Zemplén County mainly in Gönc region which is one of the most important apricot growing regions in Hungary, named “Gönc Apricot Growing Area”. Our goals were to diagnose the occurrence of Ca. Phytoplasma prunorum on stone fruits (especially on apricot) in the North-Hungarian growing areas by visual diagnostics and confirm data by laboratory PCR-based examinations. All the 28 collected samples were tested in laboratory trials and at 13 samples from apricot, peach, sour cherry and wild plum were confirmed the presence of phytoplasma (ESFY). On the base of observations it seems evident that the notable losses caused by "Ca. Phytoplasma prunorum" is a new plant health problem to manage for fruit growers, especially apricot producers in Hungary. 

  • Distribution of the American grapevine leafhopper (Scaphoideus titanus Ball 1932) in surroundings of Nagyvárad (Oradea, West Romania) and Debrecen (East Hungary)
    39-44
    Views:
    158

    The first European appearance of american grapevine leafhopper (Scaphoideus titanus), which is the vector of Grapevine Flavescence Dorée phytoplasma (‘Ca. Phytoplasma vitis’), were detected in France in 1924. The leafhopper has been distributed since 2006 in Hungary and now it occurs in the whole country, while the first record of the phytoplasma was published in 2013.
    We studied the distribution of the leafhopper in surroundings of Nagyvárad (Oradea, West Romania) in 2015 and surroundings of Debrecen (East Hungary) in 2016. During the studies 17 sites were sampled. The leafhoppers were found in six Romanian places with relatively low abundances while it occurs in all studied Hungarian sites and two of them showed extremely high frequenncy.

  • Phytoplasma infection status survey in plum psyllid (Cacopsylla pruni) population
    45-48
    Views:
    125

    European Stone Fruit Yellows (ESFY) phytoplasma disease causes an increasing amount of damage. This is especially true to the Gönci growing region. The insect vector of the disease, which has been shown to have a vector role during transmission experiments, is the plum psyllid (Cacopsylla pruni). In 2018, during the swarming period of plum psyllid, in 3 different settlements (Boldogkőváralja, Nagyvárad and Bekecs) 265 psyllidswere collected, from which 165 were plum psyllid. Molecular biology studies showed 106 individuals infected with phytoplasma, of which 20 were males and 86 were females.

  • Distribution of the American grapevine leafhopper (Scaphoideus titanus ball 1932) in west Romania
    127-130
    Views:
    154

    The vector of Grapevine Flavescens Dorée phytoplasma, the American grapevine leafhopper (Scaphoideus titanus) has been in Europe since 1924. In Romania, the first populations were detected in 2009 in the central, eastern and southern part of the country. Later, the leafhopper was found also in West Romania in 2014. In 2015 and 2017, altogether, 14 sampling sites were studied in two vine regions of this area. The Scaphoideus titanus could be detected in 10 of them with relatively small abundances. During the studies, the yellow sticky traps proved more effective methods than sweep netting. To prevent vineyards from disease, we should do everything against the vector from prevention to chemical protection.

     

  • Ideas on the European stone fruit yellows – as an entomologist can see them
    30-34
    Views:
    172

    The European stone fruit yellows (ESFY) is an important endemic disease in Europe which causes in both, the Mediterranean countries and Central Europe serious damage. Its pathogen is the ‘Candidatus Phytoplasma prunorum’. The treatment and healing of the diseased trees and plantations with chemicals do not promise success. Thus, prevention may be the only solution. The transmission and spread of the pathogen happen by infected propagation material (grafting) or a vector (the psyllid, Cacopsylla pruni). Mechanism of the pathogen’s transmission and population dynamics of the vector have been extensively investigated in several European countries, which may allow by the control of C. pruni even to hold back the disease. Diseased stone fruit trees and wild Prunus spp. as main host species play an important role in maintaining and spreading the pathogen. C. pruni collects the pathogen by feeding on these plants and it carries persistently ‘Ca. P prunorum’. Researchers in Hungary have been characterized the disease only in terms of plant pathology, but neither the significance of the vector nor the role of wild Prunus spp. have been studied. This summary intends to give clues to these researches, that not only axe and saw should be the instruments of national control, but knowing the role and population dynamics of the vector the stone fruit production should be more successful.

  • Examination of the plum psyllid (Cacopsylla pruni Scopoli), a vector of European Stone Fruit Yellows (ESFY) phytoplasma in the countryside of Boldogkőváralja (Hungary)
    5-11
    Views:
    211

    European Stone Fruit Yellows(ESFY) phytoplasma disease on apricot was identified by molecular methods for the first time in 1992 in Hungary. Currently, the pathogen is known as’ Ca. Phytoplasma prunorum’. Since, the pathogen become wide-spreaded and manyof the apricot-plantations had to be eliminated. In 2009 and 2010 in the countryside of Boldogkőváralja the infection of the apricot-plantations was about 77%. As the disease spreading and causing large damages, we studied the roleo fpossible vector,the plum psyllid (Cacopsylla pruni Scopoli) in the areas of Boldogkőváralja, North-East-Hungary. Studies were done in the year of 2016, monitoring the behaviour of the psyllids in four different areas, and caught 41 them for further examination. We collected plant samples from those apricot trees, on which the plum psyllids were caught.

  • Examination of the American grapevine leafhopper (Scaphoideus titanus Ball) in Debrecen and Micske (Misca, West Romania)
    77-81
    Views:
    130

    Grapevine flavescence dorée (FD) was detected first in Hungary in 2013 in Zala County (South-West-Hungary). The disease is a serious danger for grapevine growing and grapevine propagating production. In 2014, the pathogen has been found in several new places in Hungary, viz. in Vas and Fejér Counties, and it was also detected in the former location in Zala County. The american grapevine leafhopper (Scaphoideus titanus) is the main vector of the disease. This pest was detected first in Hungary in 2006 and then it has spread all over the country. Since we have not detailed distribution data of this pest in surroundings of Debrecen, therefore we made observations in this region in 2014. The presence of the pest was confirmed by yellow sticky cards in two locations in Debrecen and another site in West Romania near to Hungarian border. We found that S. titanus is present in each sampled sites that cause serious potential danger for the appearance and spread of Grapevine flavescence dorée (FD) in this region.

  • Review of the biology of plant psyllid (Cacopsylla pruni, Scopoli 1763), and its role in the spreading of European stone fruit yellows, ESFY-phytoplasma with Hungarian data
    25-33
    Views:
    295

    The European stone fruit yellows (ESFY) phytoplasma disease caused by pathogen ’Ca. Phytoplasma prunorum’ induces serious damages in cherry, sour cherry, peach, and apricot orchards mostly in Europe. Its known vector is the plum psyllid (Cacopsylla pruni). Many articles report on the biology (morphology, taxonomy, life cycle etc.) and the method of transmission of the pathogen by the vector, and the possibilities of their control. This paper reviews our knowledge about the vector, and summarises the results of an inland research carried out in a northeastern Hungarian apricot orchards. Our goal was to show some important data for the farmers or anyone who is interested in this disease and its vector. And give some known method that we can protect our orchards against them to prevent the appearance of the disease. As the psyllid that became infected with the pathogen can hold its infectionous capacity during their lifetime, it is very important to have enough knowledge about their lifecycle, that we can determine the right time and method to control them. We also have to know how to identify them; therefore, this paper lists several important data which can be helpful. The most important keys of identification are their wing color, which dark borwn in the apex and brown is in the remaining part of the forewing. The length of the antennae is also an important factor, since other genuse’s species have longer antennae than twice the width of the head. C. pruni has as long antennae as twice the width of the head. They return to Prunus species in early spring and we have to protect our orhards in this period against them. We have to use preparations with a knock down effect on them to prevent the inoculation of the pathogen into the trees in our orchards.