Thirty-nine field populations of Frankliniella occidentalis (Pergande) were collected from different crops (sweet pepper, tomato, lettuce, artichoke, melon, cucumber, carnation, broad bean, peach and plum) in Murcia (south-east Spain). All populations were reared separately in the laboratory to obtain enough individuals for bioassays. Female thrips were bioassayed, using a standard topical application method, against methiocarb, methamidophos, acrinathrin, endosulfan, deltamethrin and formetanate. Methiocarb was the only insecticide that showed a high efficacy against F occidentalis at field dose rates. Acrinathrin and methamidophos were moderately effective, while endosulfan and deltamethrin were ineffective. Only moderate levels of resistance (Resistance Ratios at LC50 of 10-30) were detected for the selective insecticides methiocarb, formetanate and acrinathrin used against F occidentalis in crops where these insecticides are used intensively. This generalized and low level of resistance to these insecticides, coupled with a lack of efficacy for the three broad-spectrum insecticides, was observed even in intensively managed vegetable crops. Implementation of IPM strategies in Murcia has contributed to more successful insecticide anti-resistance management.

Analysis of an RNA-seq strand-specific library revealed a complete ge-nome of Hardenbergia mosaic virus (HarMV) from RNA extracted from a native wiste-ria (Hardenbergia comptoniana) plant from southwest Australia. We compared it with eight other complete HarMV genomes. It most resembled (85.8% nucleotide identity) the genome of HarMV isolate MD4-D. I n July 2016, an apical leaf sample showing obvious mosaic and deformation symptoms was collected from a plant of the indigenous southwest Australian species native wisteria (Hardenbergia comptoniana; family Fabaceae). The plant sampled also exhibited symptoms typical of phytoplasma infection (leaf chlorosis, proliferation of axillary shoots, and stunting). It was growing on a fence line bordering a playing field area in the Victoria Park suburb of Perth in southwest Australia. Hardenbergia mosaic virus (HarMV; genus Potyvirus, family Potyviridae) causes a conspicuous disease in native wisteria plants, is spread nonpersistently by aphids, and, like native wisteria itself, is indigenous to the region (1-5). It invades introduced lupin species (Lupinus spp.) at the interface of the local ancient ecosystem and recent agroecosystem (6, 7). Analysis of polyadenylated transcripts derived from RNAseq-stranded libraries (8-17) prepared from RNA extracted from the collected sample (designated VPK) detected one complete HarMV genome. RNA was extracted from the VPK sample using a ZR Plant RNA MiniPrepTM kit (Zymo Research) and treated with RNase-free DNase (Invitrogen). The extract was subjected to library preparation using a TruSeq-stranded Ribo-Zero plant kit (Illumina, catalog no. RS-122-2401) and was subsequently subjected to quality control (8-17). The library was sent to Macrogen, Inc. (South Korea), where sequencing was done using the HiSeq 2500 platform with a TruSeq SBS version 4 kit (Illumina) with 151 cycles of paired-end reads. Reads were then assembled and genomes annotated using CLC Genomics Workbench version 6.5 (CLC bio) and Geneious version 8.1.7 (Biomatters) (18, 19). The VPK sample yielded 13,609,056 reads and, after trimming, 12,972,958 remained. De novo assembly generated 25 contigs and 622,179 reads mapped to the contig of interest with a coverage of 9,107. The complete genome obtained was named VPK-1. It consisted of 9,621 nucleotides (nt) and coded for 10 proteins, which is similar to other potyviruses (20, 21). There were eight other complete HarMV genomes already in GenBank (3, 7). A BLAST-based search (22) revealed that sequence VPK-1 most resembled the sequence of HarMV isolate MD4-D (KJ152157) with an 85.8% nt identity. In addition, the analysis revealed a partial sequence (6,002 nt in length) named VPK-2,

Nesidiocoris tenuis Reuter (Heteroptera: Miridae) is one of the most controversial dicyphines because of the injuries it causes to tomato (Solanum esculentum) crops. The aim of this study was to quantify the impact of N. tenuis on fruit yield. Tomato plants were exposed to an average of 0.53 +/- 0.26, 3.4 +/- 1.1, 12.0 +/- 1.4, and 35.2 +/- 7.7 N. tenuis per plant for 3 wk. When fruit were exposed to N. tenuis as flowers, the percentage of aborted fruit was higher in compartments infested with N. tenuis, and this was related directly to the cumulative number of N. tenuis (CNN). However, compartments with the highest abortion rates had heavier and bigger fruit and were not significantly different from the controls. The variation in fruit weight was satisfactorily explained with a logistic equation in relation to the proportion of aborted fruit. To estimate the density thresholds, the variation in truss weight was predicted as a function of fruit weight and aborted fruit. The two latter variables were expressed as a function of the CNN. A maximum of 15% truss weight overcompensation was predicted at 15.8% of fruit abortion. Yield reduction was predicted at fruit abortion rates > or = 27.7%, which corresponded to 566 CNN per plant or 32.11 CNN per leaf. N. tenuis may be considered a useful predator of small pests in tomato crops if kept under these thresholds. Mathematical models predict a yield increase and fruit upgrade that overcompensates for the reduction in the number of fruit below the density threshold.

The development time for eggs and nymphs and female fertility were determined for Nesidiocoris tenuis Reuter (Het., Miridae: Dicyphini) at 15, 20, 25, 30, 35 and 40 ± 1°C, using tomato, Solanum esculentum (Miller), as substrate and eggs of Ephestia kuehniella Zeller as substitute prey. At 40°C, N. tenuis was unable to develop and barely reproduced. Egg development ranged from 30.8 days at 15°C to 6.3 days at 35°C. The cumulative thermal requirements for the eggs were 148.6 degree days (°d) and the lower thermal threshold, 10.3°C. The duration of the nymphal instar decreased from 55.9 days at 15°C to 8.6 days at 35°C. The thermal constant for the nymphs was 182.3 °d and the lower thermal threshold 11.7°C. No nymphs survived at 40°C, and the highest mortalities were at extreme temperatures (15 and 35°C). Female and male weights were influenced significantly by temperature. The fertility of N. tenuis females was reduced greatly at 15 and 40°C. The highest fertility during an observation period of 18 days following female emergence (79.5–60.0 nymphs per female) was within the temperature range of 20 to 35°C. Fertility was related directly to female weight and temperature (r2 = 0.932). Based on development, reproduction data and thermal requirements, the optimum temperature range for N. tenuis was established as being between 20 and 30°C. Overall, N. tenuis is the most thermophilous of all dicyphines from vegetable crops in the Mediterranean area studied so far.

Response of western flower thrips, Frankliniella occidentalis (Pergande), to selection for resistance to insecticides commonly used to control this pest in Murcia (south-east Spain) was studied under field and laboratory conditions. In the field, plots within sweet pepper crops in commercial and experimental greenhouses were treated under different selection strategies: insecticide rotation versus formetanate reiteration, formetanate reiteration versus acrinathrin reiteration, and formetanate reiteration versus methiocarb reiteration. Thrips populations were sampled monthly and bioassayed against methiocarb, methamidophos, acrinathrin, endosulfan, deltamethrin and formetanate. In the laboratory, F occidentalis strains were selected against each insecticide for several generations. To evaluate cross-resistance, each selected strain was bioassayed with the other insecticides. Frankliniella occidentalis populations showed a rapid development of acrinathrin resistance, reaching high levels in field and laboratory conditions. Formetanate and methiocarb resistance were also observed, although development was slower and at moderate levels. Cross-resistances between acrinathrin/deltamethrin and acrinathrin/formetanate were detected under field and laboratory conditions. Formetanate/methiocarb cross-resistance was suspected in laboratory selections, but not in field assays. Simultaneous moderate resistance levels to the three specific insecticides against thrips (formetanate, methiocarb and acrinathrin) were shown in laboratory selection strains, indicating a general mechanism of resistance, probably metabolic.

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At the beginning of 2000, a damaging disease developed on protected tomato (Lycopersicon esculentum) crops grown in polyethylene greenhouses in different regions of Spain. Production losses were estimated at 15 to 80%. The tomato plants showed a variety of symptoms. The most common symptoms were leaf distortion, chlorosis, and mosaic. Some plants showed a dark green mosaic and bubbling of the leaf surface. Green striations were also observed on the stem and sepals. Most of the diseased plants had discolored fruits. Symptoms decreased as environmental temperature increased. The involvement of Pepino mosaic virus (PepMV) was suspected. To identify the etiological agent, ≈500 symptomatic tomato plants were collected from several locations in Alicante, Murcia, Almeria and the Canary Islands. Flexuous viral particles 510 nm long were observed by transmission electron microscopy, suggesting the presence of a potexvirus in the tissue extracts analyzed. All samples were tested by ELISA (enzyme-linked immunosorbent assay), using polyclonal antibodies to Narcissus mosaic virus (Adgen, Auchincriuve, Scotland), a virus serologically related to PepMV, and two antisera specific to PepMV (Adgen, Scotland and DMSZ, Braunschweig, Germany). PepMV was detected in 35% of the samples. Like PepMV, the virus infected (as confirmed by ELISA) greenhouse-grown Datura stramonium, Nicandra physalodes, Nicotiana benthamiana, N. clevelandii, Solanum tuberosum, and Vigna sinensis and did not infect Capsicum anuum, Cucumis sativus, Chenopodium amaranticolor, C. quinoa, Petunia × hybrida, Phaseolus vulgaris, Physalis floridana, N. glutinosa, N. rustica, or N. tabacum. The virus did infect Gomphrena globosa, which normally is not infected by PepMV. The first report of PepMV was on pepino (Solanum muricatum) in Peru in 1974 (1), but this virus has been recently reported in the Netherlands, England, Germany, and France on protected tomato crops (2). To our knowledge, this is the first report of PepMV in Spain, including the Canary Islands. References: (1) R. A. C. Jones et al. Ann. Appl. Biol. 94:61, 1980. (2) European and Mediterranean Plant Protection Organisation (EPPO). Alert List Viruses. On-line publication/2000/003.