Projects / Programmes
Can global climate changes influence the settlement of tropic plant parasitic species new to Slovenia, the example of Meloidogyne ethiopica?
| Code |
Science |
Field |
Subfield |
| 4.03.00 |
Biotechnical sciences |
Plant production |
|
| Code |
Science |
Field |
| B390 |
Biomedical sciences |
Phytotechny, horticulture, crop protection, phytopathology |
plant parasitic nematodes, root knot nematodes, Meloidogyne ethiopica, bionomics, virulence, genetic characterization, global climate change
Researchers (9)
Organisations (2)
Abstract
Root-knot nematodes Meloidogyne spp. are obligatory pests of several mono- and dicotyledons. They are able to induce swellings (root galls) on the host roots on which they develop and propagate. Meloidogyne spp. belong to the economically important harmful organisms. The extent of harm caused depends on the host type and the root-knot nematode species. More than eighty nominal species have been described worldwide while 21 species have been detected in Europe so far. Until now only four species: M. hapla, M. incognita, M. arenaria in M. ethiopica have been detected in Slovenia. According to possible economic influence of M. ethiopica, lack of information about its spreading and especially lack of information concerning its influence on the quality and quantity of crop production in Slovenia, we intend to study this group of plant parasites more intensively. We will focus in particular on the species M. ethiopica which was first described in Africa and for the first time encountered in Slovenia in 2003. This was also its first find in Europe. In this research project the presence of individual species of this genus and geographic spread of individual species in Slovenia will be studied more systematically. In the frame of the study of M. ethiopica we will try to determine the host plants which can be parasitised by M. ethiopica using the pot-experiments. We will focus on the host plants typical for the Primorska region of Slovenia. The capability of surviving of M. ethiopica in the Slovene climate conditions and the length of one whole generation of M. ethiopica with regard to various temperatures will be determined. Various scenarios of climate changes occurring in Slovenia will be analysed, their influence on development abilities of the species M. ethiopica will be studied and an analysis of risk of settlement and spreading of this species in Slovenia will be made. We will study the genetic variability of individual populations of M. ethiopica and define the presence of virulent and avirulent genes in M. ethiopica. We will also define the virulence of M. ethiopica according to the presence of Mi resistance gene in the most frequently used Slovene cultivars of tomato plants.
Significance for science
The present study has contributed to new knowledge on survival and reproduction of the tropical root-knot species M. ethiopica. Biotests on different host plants were performed to determine host range of the species. Twenty two new host plants for M. ethiopica were established in our tests. The pest can multiply on dicotyledonous as well as on monocotyledonous plants.
The relationship between the morphological changes of Meloidogyne ethiopica-infested roots and the physiological responses of tomato plants were also examined.
It was proven for the first time in Europe that M. ethiopica could survive the open field winter conditions at continental climate that is characterised by hot summers and cold winters, as well as in a sub-Mediterranean climate characterised by hot summers and mild winters.
Furthermore, the influence of temperature on the reproduction cycle of M. ethiopica was investigated. The data obtained from these experiments were used to develop a correlation between temperature and the time needed for M. ethiopica to complete a reproduction cycle using a mathematical equation. The reproduction curve determined from our results represents a useful tool for further applied research on the biology of this pest species as well as for predicting of its incidence.
The data obtained in this project represent groundwork for more intensive studies needed for a thorough pest risk analyses (PRA) to determine the threat this pest poses to agricultural production in Europe. On the basis of our research the process in which M. ethiopica was listed on Alert list of harmful organisms was initiated within the European and Mediterranean Plant Protection Organization (EPPO).
The sequences of M. ethiopica populations from Slovenia and Brazil showed a 99.7% of sequence similarity score and clustered together with high bootstrap support.
In addition, it was demonstrated that the resistance Mi gen is also effective against M. etiopica. This will help in examinig options for control strategies agains M. ethiopica.
Significance for the country
The most commonly found root-knot nematodes in Slovenia are M. incognita (isolated mainly from host plants growing in greenhouses) and M. hapla, isolated from the roots of host plants grown in the open fields. M. ethiopica was isolated from heavily infested roots of tomato plants grown in a greenhouse situated in the village Dornberk in 2003 only once. All other samples, analysed on the presence of M. ethiopica have been negative.
Based on our studies, twenty two new host plants for M. ethiopica were established. The results obtained in our studies are very worrying because this tropical species is very polyphagous and can multiply on dicotyledonous as well as on monocotyledonous plants. Based on results related to the range of host plants it can be ascertained that production of vegetable crops that are relevant to Slovenian agricultural production could be threatened, especially when their production take place in the open field. Control strategies based on crop rotation considered useless because of the wide range of host plants that can be parasitized by M. ethiopica.
To create and implement an effective pest management strategy against M. ethiopica it was important to determine host plant status of plants that are important for slovenian agriculture production. In terms of host status, tomato and bean were considered as excellent hosts, spinach, mangold and beet were identified as good hosts, while Brassica species were shown to be a poor hosts.
The information that M. ethiopica is able to survive during the winter in open fields in Europe is very important. It was demonstrated that M. ethiopica was able to survive at at regions with sub-Mediterranean and continental European climates and also that it retained its infection ability although temperatures below zero were recorded. The results of this research project represent key information that are required for conducting Pest Risk Analyses (PRA) which are available to the public, Phytosanitary Administration of RS and other experts at Ministry of agriculture, forestry and food.
Most important scientific results
Annual report
2008,
2009,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
2009,
final report,
complete report on dLib.si
