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1.
A new species,Tamarixia sheebae, is described and illustrated.Tamarixia sheebae differs fromT. bicolor Mercet andT. radiata Waterston in having the apex of gaster tilted upwards. It emerged from leaf galls ofTerminalia arjuna (Roxb.) Wright & Arn. (Combretaceae), a tree with many medicinal properties in addition to its timber value.  相似文献   

2.
In October 2019, unusual damage was observed on Carissa macrocarpa (Apocynaceae) fruit at the ornamental nursery of the Higher Agronomic Institute (ISA CM), Chott Mariem (Sousse, Tunisia). Samples of fruit were collected and brought to the laboratory for observation and rearing. After a few days, adult flies emerged from infested fruit. Zaprionus indianus Gupta, Z. tuberculatus Malloch (Diptera Drosophilidae) and Ceratitis capitata Wiedemann (Diptera, Tephritidae) were identified morphologically. Information on the morphology, distribution and ecology of the two Zaprionus species are provided. This is the first record of Z. indianus and Z. tuberculatus in Tunisia.  相似文献   

3.
The Asian chestnut gall wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera, Cynipidae), is one of the most damaging insect pests on Castanea sativa Miller trees (Fagales, Fagaceae) worldwide. Dryocosmus kuriphilus galls were collected between late May and August 2014 from 11 sites in the Friuli Venezia Giulia region of North‐East Italy, differing in elevation and forest cover composition. The number of parasitoids that emerged was higher than the number of D. kuriphilus specimens that emerged for 5 out of 11 sites considered. The mean number of larval chambers per gall dissected was between 1.5 and 2.8 (for the 11 different sites). There were no fewer than 2–3 specimens of parasitoids emerging per 100 galls, in all sites. The parasitoids identified belonged to five different Chalcidoidea families (Torymidae, Eupelmidae, Eurytomidae, Pteromalidae and Eulophidae). Among them, Torymidae and Eupelmidae represented approximately 90% of the total hymenopteran parasitoids. The most represented species were Torymus flavipes (Walker), Megastigmus dorsalis (Fabricius) and Eupelmus urozonus Dalman, all indigenous parasitoids of species causing oak galls. All identified parasitoids were already known to be associated with D. kuriphilus in Italy. These data support the hypothesis of a high species richness of this parasitoid community.  相似文献   

4.
5.
In August 2013, Phenacoccus madeirensis Green, 1923 (Hemiptera: Pseudococcidae) was identified for the first time in Tunisia, in the region of Akouda (Sousse, coastal area of Tunisia) on Cestrum nocturnum (Solanaceae) during a survey. The infestation was observed on leaves, shoots and also on the collar. This is the first record of P. madeirensis in Tunisia and the first record of this pest in North Africa. Two other mealybugs Peliococcus cycliger and Planococcus citri were also recorded during this survey. They have previously been reported in Tunisia.  相似文献   

6.
During January 2019, mealybugs were observed on branches of olive trees (Olea europaea, L.) for the first time at Nebeur and Charket Saboune (Governorate-Kef, Tunisia). Samples were collected and brought to the laboratory for identification. The mealybug species was identified based on its morphological characteristics as Pollinia pollini (Costa, 1857) (Hemiptera, Asterolecanidae). This is the first report of this species in Tunisia.  相似文献   

7.
M. Ehsine  F. Aoun 《EPPO Bulletin》2020,50(2):304-306
In October 2019, Spoladea recurvalis (Fabricius, 1775) (Lepidoptera: Crambidae) was identified for the first time in Tunisia, in the geothermal site of Saaidan and the geothermal site of El Mansoura (Kebili, south western region of Tunisia). Damage was observed on melon, chard, beet and weeds. This is the first record of S. recurvalis in Tunisia.  相似文献   

8.
In 2004, bacterial galls were found on the roots of carrots in Shizuoka Prefecture, Japan. Galls were about 0.1–2 cm in diameter, light brown in color and had rough surfaces. In 2005, similar galls were found on the roots of three weeds: henbit (Lamium amplexicaule L.), Persian speedwell (Veronica persica Poir.) and leaf mustard (Brassica juncea L.). A bacterium that forms white, rough colonies was isolated from the carrot and weeds galls. The bacterial isolates had properties identical with Rhizobacter dauci Goto and Kuwata. Phylogenetic analysis based on 16S rDNA sequences showed that the carrot isolate had the highest homology (similarity of 100%) with that of the type strain of R. dauci. Rep-PCR genomic fingerprinting using BOX A1R primer showed that the carrot and weeds isolates were nearly identical. Pathogenicity of the isolates was confirmed by inoculating the roots of carrots and the weeds. After 2–5 weeks, they formed galls on the roots of the original host species and on other plant species tested. The galls were indistinguishable from those formed naturally, and the inoculated bacterium was reisolated. Thus, the causal bacterium of carrot and weeds gall was identified as R. dauci, and the bacterium was found to have a wider host range than previously known. These weed hosts may serve as inoculum sources for carrot bacterial gall disease.  相似文献   

9.
During the summer and autumn of 2014 the mealybugs Maconellicoccus hirsutus (Green, 1908) (Hemiptera: Pseudococcidae) and Phenacoccus peruvianus Granara de Willink, 2007 (Hemiptera: Pseudococcidae) were observed in different localities of Sousse (Tunisia). This is the first record for both of these species in Tunisia and in North Africa. For M. hirsutus, this was also the first record of the species in a Western Mediterranean country. It was observed on Hibiscus rosa‐sinensis (Malvacae). P. peruvianus was collected from Bougainvillea glabra (Nyctaginaceae) and Citharexylum quadrangularis (Verbenacae).  相似文献   

10.
The pomegranate butterfly Deudorix (=Virachola) livia Klug 1834 (Lepidoptera: Lycaenidae) was encountered for the first time infesting dates (Phoenix dactylifera, variety Deglet Nour) in the oasis of Gafsa, Southern Tunisia in September 2011. Larvae of D. livia only caused damage on date fruits at the phenological stages kimiri (green fruits) and khalal (yellow fruits). The average infestation rate of dates was 10%. In addition, 7.1% of the infested fruits dropped to the ground. Damage caused by this insect on dates is described, the current situation in Tunisia is provided and possible control methods in Tunisia are briefly discussed. Although this pest has previously been reported in Tunisia on pomegranate this is the first report of D. livia on dates in the country.  相似文献   

11.
Abstract

Trials were conducted from 1979 to 1983 at Pantnagar on the effect of 2,4‐dichlorophenoxy acetic acid (2,4‐D) (5 to 250 mg/litre), 2,4,5‐trichloroxyphenoxy acetic acid (2,4,5‐T) (5 to 250 mg/litre), 1‐naphthyl acetic acid (NAA) (5 to 500 mg/litre), chlorocholine chloride (CCC) (50,100 mg/litre), naleic hydrazide (MH) (50, 100 mg/litre), abscisic acid (10, 50 mg/litre), gibbrellic acid and Alar (10 and 50 mg/litre) on the gall formation in mango by Apsylla cistellata Guckton. There was no effect on the number of galls formed but abnormal, open, elongated galls were formed in the case of 2,4‐D (100 mg/litre and above) and 2,4,5‐T (150 mg/litre), in which nymphs of A. cistellata could not survive, resulting in control of the pest. No flower panicles emerged on the twigs with no nymphal population.  相似文献   

12.
The occurrence of fungicide resistance in Mycosphaerella graminicola populations from Tunisia was investigated by examining mutations known to be associated with strobilurin and azole resistance. Few mutations associated with fungicide resistance were detected. No evidence for strobilurin resistance was found among 357 Tunisian isolates and only two among 80 sequenced isolates carried mutations associated with azole resistance. A network analysis suggested that these mutations emerged independently from mutations found in previously described European populations. The population genetic structure of M. graminicola in Tunisia was analyzed using variation at 11 microsatellite loci. Populations in Tunisia were characterized by high gene and genotype diversity. All populations were in gametic equilibrium and mating type proportions did not deviate from the 1:1 ratio expected under random mating, consistent with regular cycles of sexual reproduction. In combination with a high degree of gene flow among sampling sites, M. graminicola must be considered a pathogens with high evolutionary potential. Thus, control strategies against Septoria blotch in Tunisia should be optimized to reduce the emergence and spread of resistant isolates.  相似文献   

13.
The pumpkin fly Dacus frontalis is reported in this paper for the first time in Tunisia, where it was found in several locations. It is a pest of cucurbits of economic importance and is common especially in the eastern and southern parts of Africa. D. frontalis was collected from infested cucumber fruits in the region of El‐Jebil (Kairouan) and female bait traps for the Mediterranean fruit fly Ceratitis capitata and the olive fly Bactrocera oleae. Preliminary data from Tunisia suggest that D. frontalis is already established in four regions in which cucurbits are important crops. Brief notes on the diagnostic features for the species, its ecology and geographic distribution are given. Symptoms on cucumber from Tunisia are presented.  相似文献   

14.
During an inventory study of thrips species carried out in the central‐eastern coastal region of Tunisia in 2010 and 2011, Bregmatothrips dimorphus (Priesner, 1919) (Thysanoptera; Thripidae) was found on two host plants; barley (Hordeum vulgare Linnaeus) and sorghum (Sorghum bicolor Moench). This is the first record of B. dimorphus in Tunisia. Its distribution in other parts of the world and taxonomic characteristics are briefly presented.  相似文献   

15.
The occurrence frequency of galls caused by insects and mites on the leaves of Fraxinus excelsior L. was investigated, based on leaf samples collected in the Ojców National Park in 2000–2001. The species composition of galls was identical in two consecutive years. Galls were caused by 5 species a total of 2881 galls. The most numerous species was Dasineura fraxinea (Kieffer) in both years.Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Dasineura fraxinea and Vasates fraxini (Nalepa) in 2000 as well as D. fraxinea and Psyllopsis fraxini (L.) in 2001.  相似文献   

16.
Summary On account of recent records ofDitylenchus radicicola (Greeff, 1872)Filipjev, 1936 in Dutch meadows, a study was made of its biology. Literature data were summarized.The eelworm attacks the roots of Gramineae and causes spiralshaped galls, which may contain up to 60 adults and some thousands of eggs and larvae each. Young larvae may actively hatch in water from whole, undecayed galls at temperatures around 17°C (Graph. 1). Root exudate of host plants did not stimulate the hatching process. The first larval stage is infective and may penetrate young root tips and also young galls (Fig. 1); it can withstand 2 month desiccation and also desinfection in a solution of an organic mercury compound. The host plant influences the number and size of the root galls (Graph. 2). Fig. 2 shows the anatomy of a young gall.The parasite is only found in grasses in this country and damage has not yet been found. Rye, wheat, barley and oats proved to be susceptible in inoculation trials; 17 plant species have been mentioned as natural hosts in different countries now and 3 are only found susceptible in inoculation trials.  相似文献   

17.
Hypocryphalus scabricollis (Eichhoff) (Coleoptera, Curculionidae, Scolytinae) is a new pest on fig trees (Ficus carica L.). The severe damage observed on this host in Tunisia is described and illustrated. This paper describes the morphological identification of the species and gives information on the biology of the pest and initial recommendations for its control. This is a first report for Tunisia.  相似文献   

18.
In the context of an epidemiological study on Potato virus Y (PVY) in potato crops, Solanum elaeagnifolium Cav. was included in the weeds prospected. Surveys were carried out in four seed potato areas: Cap Bon, Manouba, Jendouba and Kairouan. S. elaeagnifolium was found in all areas, except Cap Bon. Virus‐like symptoms were observed on some S. elaeagnifolium plants in the field, i.e. leaf mottling and curling. Aphids were collected on these plants and were identified as Myzus persicae and Aphis fabae, both known to colonize potatoes and to transmit the standard PVYN isolate with transmission efficiencies of 95% and 43%, respectively. Forty‐seven plant samples were tested with ELISA for the presence of PVY. Positive reactions were obtained from 2/6, 5/18, 8/23 samples collected in Manouba, Jendouba and Kairouan, respectively. Virus transmission was carried out using M. persicae as vector from two samples of each region onto plantlets of Nicotiana tabacum cv Xanthi. All inoculated plantlets displayed typical symptoms of the PVYN strain group, confirmed by serological testing using specific antibodies. This is the first report of a PVY natural infection on S. elaeagnifolium in Tunisia. The abundance of this weed, its over‐wintering status and the high rate of PVY‐infected plants (31.9%) allow us to deduce that S. elaeagnifolium must be considered a reservoir species of PVY under natural conditions in Tunisia and probably in other Mediterranean countries. The presence of efficient aphid vectors of PVY on this weed in crops is additional evidence that S. elaeagnifolium may become a problem by acting as a source plant for PVY spread in potato crops.  相似文献   

19.
Agrobacterium tumefaciens (AT) is the causal agent of crown gall, a major problem in the family Rosaceae and particularly for Prunus spp. Crown gall symptoms result from the bacterial infection of the cells damaged mechanically at the collar or by root parasitic nematodes. Myrobalan plum (P. cerasifera) is susceptible to AT and is not a host for the root-knot nematode (RKN), M. hapla. Some clones of this plum carry single Ma resistance genes that control M. arenaria, M. incognita and M. javanica. The four above mentioned RKN and Myrobalan progenies segregating for Ma were used in experiments aimed at obtaining a better knowledge of the interaction between AT and RKN in relation to the RKN resistance genes. Prunus rooted cuttings, naturally infected with the bacterium were repotted, grown and inoculated individually with RKN. In a first experiment, Prunus plants were (i) either inoculated with 10,000 juveniles (J2s) of M. arenaria to provide a short inoculum pressure (SIP) or (ii) inoculated by association with one M. arenaria-galled tomato root system that produced a high and durable inoculum pressure of the same nematode species. Four months after RKN inoculation, plants were rated for nematode and bacterial root galling symptoms. RKN and AT galls were more numerous and more homogenous under DIP than under SIP. Nevertheless, for both inoculum regimes, AT galls were present in the RKN-susceptible clones (= carrying none of the Ma genes) and absent in the RKN-resistant clones. Subsequent experiments, conducted under DIP with M. arenaria, M. incognita, M. javanica and M. hapla, also showed, for the three first species, the presence of AT galls only in RKN-susceptible clones whereas Prunus plants inoculated with M. hapla and nematode-free controls were free of AT galls. Consequently RKN act as a wound agent in the AT infection process of Myrobalan plum only when the plant develops a compatible reaction (i.e. when it lacks the Ma resistance genes). Considering that J2s do penetrate the roots of resistant plants, the absence of crown gall symptoms on this material even under durable inoculum pressure strengthens the hypothesis that this nematode stage has a very weak effect on plant cells during the infection process. This is the first evidence of the protective effect of a RKN resistance gene against the expression of root crown gall consecutive to RKN infection. The protective effect of Ma and presumably of other RKN resistance genes against AT is a strong argument for their introgression into Prunus and other Rosaceae or bacterium-susceptible crops.  相似文献   

20.
Three hawthorn and related rust diseases caused by Gymnosporangium confusum on Crataegus monogyna, Gymnosporangium clavariiforme on Crataegus orientalis and Gymnosporangium sabinae on Pyrus communis were detected in Hatay province, Turkey. G. confusum was also found causing telial galls on Juniperus communis. G. confusum and G. clavariiforme produced aecial horns on overwintered galls on hawthorn twigs from May to June. The production of galls caused by Gymnosporangium on the secondary host is unusual. Portions of the nuclear ITS and LSU rDNA were sequenced for all three species of Gymnosporangium for use as a species barcode; sequences were deposited in GenBank. Sequence data from G. clavariiforme and G. sabinae matched those in GenBank; however, this is the first study to deposit sequence data from G. confusum to GenBank. The life cycles of G. confusum and G. clavariiforme are discussed along with implications for disease control.  相似文献   

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