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La Alberca de Záncara, Spain

Mateus C.,Instituto Nacional Of Recursos Biologicos Inrb Inia | Pequito A.,Instituto Nacional Of Recursos Biologicos Inrb Inia | Teixeira S.,Instituto Nacional Of Recursos Biologicos Inrb Inia | Queiros R.,Instituto Nacional Of Recursos Biologicos Inrb Inia | And 5 more authors.
Spanish Journal of Agricultural Research | Year: 2012

A risk map for the Tomato spotted wilt virus (TSWV) was elaborated for the main Portuguese processing tomato producing region, the "Ribatejo e Península de Setúbal" region, where periodically this virus causes severe losses. Forty nine tomato fields were monitored. Risk factors for TSWV infection were identified and quantified according to their relative importance in TSWV incidence. The risk factors considered for each field were: (1) presence of TSWV in tomato plants; (2) presence of TSWV in weeds which are hosts of TSWV vectors; (3) presence of TSWV vector thrips; (4) presence of TSWV host crops previously (in the two years before), namely, tomato, potato and sweet pepper; and (5) presence of greenhouses, urban areas or TSWV host crops next to the field (up to about 100m from its borders). A risk estimator was calculated for each field. Among the thrips (Thysanoptera) identified, belonging to 11 genera, four vector thrips species were detected: Frankliniella occidentalis (Pergande) and Thrips tabaci Lindman, the two most abundant ones, and F. intonsa (Trybom) and F. schultzei (Trybom). Blue sticky traps placed up to about 75 cm above the crop canopy caught F. occidentalis and T. tabaci more efficiently than the beating technique. The weeds Datura stramonium L., Arctotheca calendula (L.), and Conyza bonariensis (L.) were identified as TSWV winter repositories. This study proposes a methodology to be used by field technicians for the annual evaluation of TSWV risk at a regional level, for an improved planning of processing tomato crop in the following season. Source

Gravalos C.,Technical University of Cartagena | Fernandez E.,Technical University of Cartagena | Belando A.,Technical University of Cartagena | Moreno I.,Technical University of Cartagena | And 2 more authors.
Pest Management Science | Year: 2015

BACKGROUND: The whitefly Bemisia tabaci Gennadius is a severe pest in many field and greenhouse crops worldwide and has developed resistance to insecticides from most chemical classes. The ease with which this pest develops resistance makes it essential to incorporate new compounds with different modes of action and no cross-resistance with those previously used into insecticide resistance management strategies. To that end, the systemic effect of the new diamide cyantraniliprole was tested with multiresistant, selected and field populations of Q-biotype B. tabaci from the Mediterranean area. RESULTS: Bioassays with multiresistant and laboratory-selected populations indicated no cross-resistance to cyantraniliprole in the B. tabaci strains exhibiting resistance to other insecticides. The LC50 values for nymphs from 14 field populations varied between 0.011 and 0.116 mg L-1, a 10.5-fold natural variability. The LC50 values for adults from three strains ranged from 0.060 to 0.096 mg L-1. CONCLUSION: These baseline data will be helpful for monitoring future potential shifts in susceptibility to cyantraniliprole in Mediterranean whitefly populations within an IRM programme. Cyantraniliprole may play an important role in mitigating insecticide resistance in B. tabaci because of its high efficacy and its lack of cross-resistance to other insecticides, even in multiresistant Q-biotype populations collected from a highly problematic insecticide resistance area. © 2015 Society of Chemical Industry. Source

Lacasa C.M.,Biotecnologia y Proteccion de Cultivos | Martinez V.,Biotecnologia y Proteccion de Cultivos | Hernandez A.,Biotecnologia y Proteccion de Cultivos | Ros C.,Biotecnologia y Proteccion de Cultivos | And 5 more authors.
Scientia Horticulturae | Year: 2015

Phytophthora capsici and Phytophthora nicotianae are the main soil-borne pathogens of greenhouse sweet pepper in Southeast (Murcia) and Pnicotianae of open field paprika pepper crops in West (Extremadura) of SpainBoth oomycete cause plant root rotThe effects of green manure amendment (Brassica carinata, Brassica nigra, Sinapis alba, non-amended as control), transparent plastic tarp (non-tarped=biofumigation, tarped=biosolarization) and depth (15cm, 30cm) were assessed for the survival of Pcapsici oospores and Pnicotianae chlamydospores in two consecutive yearsIn Murcia, biosolarization for six weeks significantly reduced the viability of oospores (values for the two soil depths ranged from 4.0-12.2% viables in biosolarized soil to 21.2-26.0% in non-treated soil in 2010 and from 6.9-31.1% to 52.4-54.9% in 2011) and the infectivity of oospores (values for the two soil depths and the two years ranged from 0.0-11.1% of diseased plants in biosolarized soil to 8.3-44.4% in non-treated soil) and chlamydospores (0.0% to 0.0-11.1%)The reduction of inoculum viability was greater with Salba and Bnigra (6.6 and 5.7% of viable oospores) than with Bcarinata (18.9%) and higher than in the non-treated soil (21.2%)Despite the low soil temperatures in Extremadura (15-29°C), Salba further reduced chlamydospore infectivity when compared to Bnigra or non-amended soil in the second year (29.2, 52.1 and 45.9% of diseased plants respectively)Biosolarization with brassicas can be recognized as an effective method to reduce Phytophthora survival in soils of greenhouse pepper crops of Murcia and with better effects on infectivity of inoculum of Pnicotianae (0.0% diseased plants) than on Pcapsici (0.0-11.1% diseased plants)Conversely, the results in Extremadura were not sufficiently consistent in the two year experiment thus, this procedure cannot be recommended for Phytophthora control in Extremadura open field. © 2015 Elsevier B.V.. Source

Larregla S.,Tecnalia | Nunez-Zofio M.,Tecnalia | Fernandez-Molina P.,Servicio de Formacion y Transferencia | Martinez-Alarcon V.,Biotecnologia y Proteccion de Cultivos | And 2 more authors.
Acta Horticulturae | Year: 2014

Phytophthora capsici is a soil fungus causing root rot in greenhouse pepper crops in southeastern Spain (Murcia and Alicante). Several factors determine soil biosolarization effectiveness to reduce pathogen inoculum in soil. The purpose of this study was to establish the effect uniquely attributable to gases released during biosolarization with fresh manure on P. capsici oospores viability. Oospores were incubated in laboratory at 20°C inside vacutainer tubes that previously were put under vacuum and refilled with gases sampled from biosolarized field plots at different time intervals during the biosolarization period. The treatments consisted of different combinations of sampling time intervals (0-2-3-4-7-9-11-14-16- 21-28 days, succession of days 9-11-14-21-28 and succession of all sampling days) and exposure times (6 to 34 days). The plots located within greenhouses were biosolarized with fresh sheep manure (7 kg m-2) during September and the length of the biosolarization period was 28 days. Oospores viability was determined with the plasmolysis method. Neither treatment completely eradicated the inoculum. Exposure to succession of gases collected during all sampling days was the most effective treatment in reducing inoculum viability, and significantly differed from control treatment (hermetic tubes with only air). The applied amendment dose and the soil temperature at 15 cm depth (daily maximum/minimum=36-45/33-40°C) were effective to achieve the critical threshold which is required for generating a sufficient amount of volatiles that reduced the pathogen inoculum viability in the conditions of the experiment. Source

Guerrero-Diaz M.M.,Biotecnologia y Proteccion de Cultivos | Lacasa-Martinez C.M.,Biotecnologia y Proteccion de Cultivos | Hernandez A.,Biotecnologia y Proteccion de Cultivos | Martinez V.,Biotecnologia y Proteccion de Cultivos | And 3 more authors.
Acta Horticulturae | Year: 2014

In two pepper greenhouses contaminated by Phytophthora and Meloidogyne incognita located in the Region of Murcia (Southeast Spain) the effect of biosolarization (solarization with organic amendments) was evaluated, with sugar beet vinasse (SBV), rapeseed milling (RM) and beer bagasse (BB) plus fresh sheep manure (FSM) for the control of soilborne pathogens, plant height, and yield. The biosolarization was initiated in August and treatments were carried out for 6 weeks. Treatments were randomized in complete block design with three replicates. Fresh sheep manure was considered as reference treatments. Viability of Phytophthora capsici, buried prior to treatments at 15 and 30 cm depth was lower in treatments with fresh sheep manure than other amendments, in one greenhouse. Control of Phytophthora sp. root rot and root-knot nematode M. incognita was good in both greenhouses. No differences between treatments in the percentage of dead root rot plants and damage from Meloidogyne sp. were observed. There were no differences among treatments for plant height and yield. No phytotoxic effects were observed for agroindustrial byproducts. Source

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