Nematodes of food legumes in the Mediterranean Basin1

Several endoparasitic nematodes have been reported on leguminous plants in the Mediterranean area. The most widespread are the root-lesion nematodes Pratylenchus mediterraneus, P. penetrans and P. thornei. Symptoms induced by these nematodes usually are not very impressive, but 50% yield loss of chickpea may occur. Among root-knot nematodes, Meloidogyne artiellia is associated with severe yield losses of chickpea in Italy, Spain and especially Syria. Tolerance limits of 0.14 and 0.02 of this nematode per ml soil are reported for winter and spring-sown chickpea, respectively. Meloidogyne incognita and M. javanica can be noxious to French bean and cowpea in sandy soil. The cyst nematode Heterodera goettingiana reduces yields of pea, broad bean and vetch when its population densities exceed 0.5, 1, and 2.1 eggs per g of soil, respectively. Heterodera ciceri occurs in northern Syria and Turkey and is responsible for economic yield losses of chickpea and lentil in fields infested with more than 1 or 2.5 eggs per g of soil, respectively. Pea and grass pea also suffer from infestation of this nematode. The stem and bulb nematode Ditylenchus dipsaci causes severe decline of broad bean, pea and probably lentil during wet seasons. Other nematodes, although present in moderate numbers, appear to have little importance.     

Control methods for potato nematodes in Ukraine1

Control of Globodera rostochiensis in Ukraine depends on the use of resistant potato cultivars. In the last 2 years, the proportion of resistant entries in the official Ukrainian list has increased from 27% to 45%, and the number of Ukrainian-bred resistant cultivars has increased from 3 to 12. It is now suggested that resistant cultivars are classified into the categories‘resistant and tolerant’ and ‘resistant but only relatively tolerant’. The choice of these cultivars should depend on the nematode population of the soil. Control of Ditylenchus destructor is also considered, on the basis of prophylactive and agrotechnical measures.     

Potato cyst nematodes in the Canary Islands: an epidemiologic model for the Mediterranean region1

This work describes studies done on the Canary Islands in order to support the elaboration of quarantine and control legislation for potato cyst nematodes which take into account the special agroecological characteristics of the Mediterranean region. The interest of the islands for epidemiological studies is based on the occurrence of the oldest potato crops in the Old World and the use of several local cultivars and traditional management cropping systems. Also, the environmental conditions allow field experiments to be performed throughout the year. The phytonematological problems of the potato crop on the Canary Islands is reported and the absence of Ditylenchus destructor, D. dipsaci, Nacobbus aberrans, Rotylenchulus reniformis and trichodorids pointed out. The cyst nematodes, Globodera rostochiensis and G. pallida were found to cause severe damage to the crop and were studied in detail by field trials at Tenerife. Continuous growing of the cv. Cara, with the H1 gene conferring resistance to G. rostochiensis (pathotypes Ro1 and Ro4), exerted selection pressure for G. pallida. Under the edaphic and climatic conditions of Tenerife, nematicide application was found to be inefficient for controlling potato cyst nematodes. Alternative control techniques based on traditional management systems and on the use of environmentally adverse conditions were investigated.     

Control of root-knot nematodes (Meloidogyne spp.) in Hungary1

Under Hungarian climatic conditions, root-knot nematodes, and other phytoparasitic nematodes, generally cause damage in certain plant growing areas. These pests are present in glasshouses throughout the country. In the field the nematodes occur in sandy soil in the vegetable-growing areas of southern and central Hungary. The following species of root-knot nematodes have so far been reported to occur in Hungary: Meloidogyne incognita, M. arenaria, M. hapla, M. javanica, M. incognita acrita, M. thamesi and M. naasi. There are 10 specific nematicides registered for nematode control in the country. These chemicals are mainly applied in glasshouses where their use produces most economic return. Nematoderesistant cultivars are only available in the case of tomato. The nematodes cause the heaviest damage on glasshouse cucumber.     

PCR-RFLP identification ofBemisia tabaci biotypes in the Mediterranean Basin

At least 20 genetic biotypes, with varying degrees of biological characterization, are currently recognized within theBemisia tabaci (Hemiptera: Aleyrodidae) species complex. Their identification relies on a set of different molecular techniques. However, none of the available markers is completely adequate, due to technical difficulties or lack of reproducibility. We therefore developed a method for rapid biotyping ofB. tabaci populations. The five biotypes (B, Q, M, S and T) reported until now in the Mediterranean Basin have been tested by PCR amplification of the cytochrome oxidase I mitochondrial gene followed by restriction with the enzymeTru9I. The digestion patterns produced by this enzyme were able to identify the five biotypes clearly. Digestion with another enzyme,TaqI, discriminated only between biotypes B and Q. The newly developed method enables rapid biotyping and can be applied in studies aimed at assessing biotype distribution and competition at least in the Mediterranean area. http://www.phytoparasitica.org May 14, 2006.     

The occurrence and distribution of nepoviruses and their associated vector Longidorus and Xiphinema nematodes in Europe and the Mediterranean basin1

Six nepoviruses are transmitted by five Longidorus and three Xiphinema species in Europe. The virus and vector associations are: L. apulus and L. fasciatus with artichoke Italian latent nepovirus, L. attenuatus and L. elongatus with tomato black ring nepovirus, L. elongatus and L. macrosoma with raspberry ringspot nepovirus, X. diversicaudatum with arabis mosaic and strawberry latent ringspot nepoviruses and X. index and X. italiae with grapevine fanleaf nepovirus. The distributions of the viruses and their vectors in Europe and the Mediterranean basin are described. The following points are commented: presence of non-indigenous nematode-transmitted nepoviruses in Europe; occurrence of vector nematodes in European countries in the absence of their associated nepoviruses; the possible vectors of serologically distinct strains of grapevine fanleaf nepovirus.     

Emerging invasive alien plants for the Mediterranean Basin

A major step in tackling invasive alien plants consists of identifying those species that represent a future threat to managed and unmanaged habitats. The European and Mediterranean Plant Protection Organization reviews and organizes data on alien plants in order to build an early warning system. A prioritization system is being developed to select species that represent emerging threats and require the most urgent pest risk analysis to implement preventive measures and to perform eradication and management measures. Attention has been drawn to the Mediterranean Basin which is particularly vulnerable because its climatic conditions potentially allow the establishment of sub‐tropical and tropical species. Surveys and rapid assessments of spread and impact have allowed identification of emerging invasive alien plants for Mediterranean countries: Alternanthera philoxeroides (Amaranthaceae), Ambrosia artemisiifolia (Asteraceae), Baccharis halimifolia (Asteraceae), Cortaderia selloana (Poaceae), Eichhornia crassipes (Pontederiaceae), Fallopia baldschuanica (Polygonaceae), Hakea sericea (Proteaceae), Humulus japonicus (Cannabaceae), Ludwigia grandiflora and L. peploides (Onagraceae), Hydrilla verticillata (Hydrocharitaceae), Microstegium vimineum (Poaceae), Myriophyllum heterophyllum (Haloragaceae), Pennisetum setaceum (Poaceae), Pistia stratiotes (Araceae), Salvinia molesta (Salviniaceae), Solanum elaeagnifolium (Solanaceae). These species represent priorities for action. Some other species are placed on the observation list, as available information does not allow them to be counted among the worst threats: Akebia quinata (Lardizabalaceae), Araujia sericifera (Apocynaceae), Delairea odorata (Asteraceae), Cabomba caroliniana (Cabombaceae), Nassella neesiana, N. tenuissima and N. trichotoma (Poaceae), Sesbania punicea (Fabaceae), and Verbesina encelioides (Asteraceae).     

Potential for classical biocontrol of silverleaf nightshade in the Mediterranean Basin

Unlike biocontrol of insect pests, biocontrol of invasive weeds is not largely studied in Eurasia, but remains an ecologically sound approach to invasive species management. The case study of silverleaf nightshade ( Solanum elaeagnifolium ) is a good example of a New World weed which has been introduced and is spreading over the Mediterranean Basin. S. elaeagnifolium economically impacts agricultural areas by competing with cereal crops, damaging pastures, and infesting meadows and roadsides. This paper deals with classical biological control of S. elaeagnifolium in the Mediterranean basin with natural enemies from the region of origin of the target plant, using studies conducted on other continents. Natural enemies are listed and their capability to attack and control the target plant is discussed. Special attention is devoted to Leptinotarsa texana and L. deflecta , chrysomelid beetles already released with success against S. elaeagnifolium in South Africa, one of the five Mediterranean-type regions of the world.     

Review of the current situation for Solanum elaeagnifolium in the Mediterranean Basin

Silverleaf nightshade (Solanum elaeagnifolium, Cav.) is one of the important invasive plant species in Mediterranean Basin countries. Over the last 60 years, this plant has gone from a few accidental introductions to near monospecific populations in many areas of the Mediterranean Basin (in particular Greece and Morocco). Recent findings from Lebanon show that the invasion is ongoing. Solanum elaeagnifolium has a negative impact on crops, causing up to 75% yield loss, as well as an indirect impact by harbouring plant pests and diseases. Solanum elaeagnifolium is toxic to livestock and has a negative affect on the quality of life for humans. Losses of potential resource or revenue caused by its invasion include: decreased forage quality on grazing lands; decreased cropping land and amenity values of public space; increased water loss; increased water conveyancing costs; and increased forest restoration costs. Available control techniques need to be strengthened to reduce the impact of S. elaeagnifolium and prevent its spread. More attention needs to be devoted to biological control, which could provide regional management of this invasive alien plant. Sustainable management of S. elaeagnifolium will require coordination, education and support across the affected countries. Governments must have the means to detect, manage and control S. elaeagnifolium.     

Plant-parasitic nematodes of Croatia1

Investigations on the distribution of nematodes were carried out mostly in the northern and eastern parts of Croatia up to 1991. Sampling was performed in the following crops: maize, wheat, barley, sugarbeet, soybean, sunflower, rape, tobacco, potato, alfalfa, blackberry, onion, carrot, cucumber, lettuce, tomato, capsicum, oak, chrysanthemum, tulip, rose, grapevine, peach, apple, plum, pear, cherry, poplar, willow, clover, nettle, grass, meadow, woodland, many species of weeds, various glasshouse crops and vegetation in a nature reserve. 63 genera of nematodes with 81 species were detected. The most numerous representatives of plant parasitic nematodes were: Anguina, Aphelenchoides, Aphelenchus, Criconemoides, Ditylenchus, Gracilacus, Helicotylenchus, Hemicycliophora, Heterodera, Longidorus, Macroposthonia, Meloidogyne, Paratylenchus, Pratylenchus, Rotylenchulus, Rotylenchus, Trichodorus, Tylenchorhynchus, Tylenchus and Xiphinema.     

不同土壤处理剂对设施蔬菜黄瓜根结线虫防治技术研究

为了筛选蔬菜根结线虫的防治技术,在赤峰市进行了7种不同土壤处理药剂对黄瓜根结线虫的防治效果田间试验,结果表明,应用7种不同土壤处理药剂进行土壤处理,揭膜放气5d后定植黄瓜,对黄瓜生长无不良影响,而且对根结线虫均有较好的抑制作用,其中98.1％1,3-二氯丙烯-氯化苦复配胶囊16 kg/667 m2、95％1,3-二氯丙烯液剂65 kg/667m2及10％液体石灰氮65 kg/667m2对黄瓜根结线虫的防治效果达90％左右,优于目前生产中常用药剂42％威百亩水剂6 kg/667m2和10％噻唑磷颗粒剂2 kg/667m2的防治效果,并且可以显著地提高黄瓜产量,适于在设施蔬菜生产上推广使用.     

Transmission of tobraviruses by trichodorid nematodes1

Transmission of tobacco rattle tobravirus by Paratrichodorus and Trichodorus has been known since 1961. However many of the studies of these virus-vector associations have been uncritical. Here we describe a system to study acquisition and transmission of individual tobravirus isolates by given species of Paratrichodorus and Trichodorus. Results from initial experiments in which this system was used suggest that different isolates of tobacco rattle tobravirus differ in vector specificity.     

Response of hydrological drought to meteorological drought in the eastern Mediterranean Basin of Turkey

The hydrographic eastern Mediterranean Basin of Turkey is a drought sensitive area. The basin is an important agricultural area and it is necessary to determine the extent of extreme regional climatic changes as they occur in this basin. Pearson's correlation coefficient was used to show the correlation between standardized precipitation index(SPI) and standardized streamflow index(SSI) values on different time scales. Data from five meteorological stations and seven stream gauging stations in four sub-basins of the eastern Mediterranean Basin were analyzed over the period from 1967 to 2017. The correlation between SSI and SPI indicated that in response to meteorological drought, hydrological drought experiences a one-year delay then occurs in the following year. This is more evident at all stations from the mid-1990 s. The main factor causing hydrological drought is prolonged low precipitation or the presence of a particularly dry year. Results showed that over a long period(12 months), hydrological drought is longer and more severe in the upper part than the lower part of the sub-basins. According to SPI-12 values, an uninterrupted drought period is observed from 2002–2003 to 2008–2009. Results indicated that among the drought events, moderate drought is the most common on all timescales in all sub-basins during the past 51 years. Long-term dry periods with moderate and severe droughts are observed for up to 10 years or more since the late 1990 s, especially in the upper part of the sub-basins. As precipitation increases in late autumn and early winter, the stream flow also increases and thus the highest and most positive correlation values(0.26–0.54) are found in January. Correlation values(ranging between –0.11 and –0.01) are weaker and negative in summer and autumn due to low rainfall. This is more evident at all stations in September. The relation between hydrological and meteorological droughts is more evident, with the correlation values above 0.50 on longer timescales(12-and 24-months). The results presented in this study allow an understanding of the characteristics of drought events and are instructive for overcoming drought. This will facilitate the development of strategies for the appropriate management of water resources in the eastern Mediterranean Basin, which has a high agricultural potential.     

Evolution and biogeography of cyst-forming nematodes1

Phylogenetic systematics is based on genealogy, rather than overall similarity, and a cladogram constitutes a potentially falsifiable hypothesis that can bring a new perspective to our understanding of the distribution and biogeography of a group of organisms. Sufficient data now exist for phylogenetic analysis of the Heteroderidae. New data at new levels of analysis comprise potential falsifiers for existing schemes.     

Citrus certification in Mediterranean countries1

Citrus suffers severe losses from virus and similar diseases, which are mainly spread by grafts, stocks and scions. This planting material needs to be made virus-free throughout the Mediterreanean region. The standards published by EPPO in 1980 remain valid for this purpose: they provide techniques for elimination of the viruses and for protecting healthy material from reinfection. The actual situation in individual Mediterranean countries is reviewed, especially with regard to certification programmes (still not started in several cases). Healthy planting material of certain cultivars can be obtained on the international market, but this is not true of local cultivars which also need to be certified. In any case, the import of planting material carries the risk of introducing diseases not yet present in the Mediterranean region, so that strict quarantine procedures are needed.     

Root-knot nematodes (Meloidogyne spp.) in Hungary1

During a routine survey which was conducted in three successive years, 1990–1992, in southeastern Hungary, it was found that Meloidogyne spp. are common on a wide host range in fields, glasshouses and polythene tunnels, especially in sandy soil between the Danube and Tisza rivers. Meloidogyne incognita, M. incognita acrita and M. arenaria were recorded to be the most important in glasshouses (at Hódmezóvásárhely, Csongrád, Mindszent, Fábiánsebestyén, Kistelek, Balástya, Szatymaz, Bordány, Mórahalom, Szeged, Apátfalva and Szegvár); M. hapla was found to be the most important species in the field (at Hódmezóvásárhely, Makó, Szeged, Szatymaz, Szentes, Domaszék, Mórahalom, Asotthalom, Bordány, Ulés, Zsombó, Balástya, Kistelek, Csanytelek, Forráskút and Rúzsa). M. thamesi was detected in certain cultivated plants and weed hosts (at Kistelek, Balástya, Rúzsa, and Gyula). Besides the cultivated plants, 41 weed plants, belonging to 34 genera in 22 families, were also found to be hosts for root-knot nematodes in fields and glasshouses. Meloidogyne naasi was found for the first time in Hungary on some grass hosts.     

昆虫线虫抑制植物线虫的机理研究进展

斯氏科(Steinernematidae)、异小杆科(Heterorhabditidae)、索科(Mermithidae)和小杆科(Rhabditidae)线虫为几类较有生物防治前景的昆虫线虫。一些昆虫线虫除了能够有效地防治有害昆虫,还具有抑制植物线虫的作用,本课题组研究发现小杆科、小杆属Rhabditis(Oscheius)的某些昆虫线虫品系也有抑制植物线虫的作用。国内在这方面报道很少,国外许多线虫研究者自20世纪80年代以来有过一些研究。本文着重报道昆虫线虫抑制植物线虫的作用机理研究进展、植物线虫的生物防治途径和昆虫线虫的应用范围。     

Plant-parasitic nematodes associated with pine trees in Bulgaria1

Literature data on the nematode fauna of Pinus spp. in Bulgaria are summarized. 48 plant-parasitic nematodes have been reported so far associated with six pine species and a variety of one of these species. In the course of the present study of pine nematode fauna in Rila and Rhodope mountains, Crossonema menzeli, Criconemella xenoplax, Bursaphelenchus sp., Longidorus vineacola, L. leptocephalus, Longidorus sp. and Trichodorus similis were found. Morphological data on some of the species studied are given. The males of L. leptocephalus was more common than the females. L. leptocephalus and Bursaphelenchus sp. are new geographical records. Pinus sylvestris is a new plant host for C. menzeli and L. leptocephalus.     

Plant parasitic nematodes as pests of potatoes in Poland1

Only two plant parasitic nematode species have practical importance in potato crops in Poland. They are Ditylenchus destructor and Globodera rostochiensis pathotype Ro1. Control of D. destructor is done permanently by the elimination of infested seed potatoes and sowing of cereals in the infested fields. Damage to potatoes is observed rather seldom. G. rostochiensis is widely distributed throughout Poland. It is controlled by non-host crops and by resistant potato cultivars. Chemical control of potato nematodes is not put into practice in Poland.     

Integrated pest management in olive in the Mediterranean area1

The FAO Interregional Cooperative Research Network on Olives is working on plant protection with the main objective of setting up an integrated pest management system aimed at controlling the main insect pests attacking Mediterranean olive orchards. The study of the factors controlling populations of both olive pests and their natural parasites and predators has therefore taken a great share of that cooperative effort. This paper reviews the work developed so far, while describing the computerized pest management programme now in use in Spain. This is directed by the national and some regional Plant Protection Services and based on the cooperation of olive growers' associations named Agrupaciones para Tratamientos Integrados (ATRIAs). Each ATRIA provides the meteorological and insect population data needed for plant protection researchers to take decisions about where and when to treat each pest.