title: Understanding trophic interactions of Orius spp. (Hemiptera: Anthocoridae) in lettuce crops by molecular methods.
abstract: BACKGROUND
  The aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) and the thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) are common pests in Mediterranean lettuce crops, where Orius spp. are common generalist predators. Predation by Orius spp. was studied in a lettuce plot by conventional polymerase chain reaction (PCR) and real-time PCR analyses using specific primers of both main pests. Also, high-throughput sequencing was used to have a wider approach of the diet of these predators in natural field conditions.
  
  
  RESULTS
  Molecular analyses indicated a higher predation on N. ribisnigri in spring and on F. occidentalis in summer. Predation on alternative prey, like Collembola, was also found in both seasons. Real-time PCR was more sensitive than conventional PCR in showing the target trophic links, whereas high-throughput sequencing revealed predation on other natural enemies - intraguild predation (IGP), showing other trophic interactions of Orius majusculus within the studied ecosystem.
  
  
  CONCLUSIONS
  This study gives important information about the trophic relationships present in Mediterranean lettuce crops in different periods of the year. The detected predation by Orius spp. on alternative prey, as well as on other natural enemies, should be further investigated to clarify whether it adds or detracts to the biological control of N. ribisnigri and F. occidentalis.
authors: IRTA, Cabrils, Barcelona, Spain.
authors: Priscila
authors: P
authors: Gomez-Polo
authors: IRTA, Cabrils, Barcelona, Spain.
authors: Oscar
authors: O
authors: Alomar
authors: IRTA, Cabrils, Barcelona, Spain.
authors: Cristina
authors: C
authors: Castañé
authors: IRTA, Cabrils, Barcelona, Spain.
authors: Thaïs
authors: T
authors: Aznar-Fernández
authors: USDA-ARS, North Central Agricultural Research Laboratory, Brookings, SD, USA.
authors: Jonathan G
authors: JG
authors: Lundgren
authors: Universitat Autònoma Barcelona, Cerdanyola del Vallès, Barcelona, Spain.|CREAF, Barcelona, Spain.
authors: Josep
authors: J
authors: Piñol
authors: IRTA, Cabrils, Barcelona, Spain.
authors: Nuria
authors: N
authors: Agustí
mesh_terms: D000818:Animals; D001042:Aphids / Q000235:genetics / Q000502:physiology*; D001483:Base Sequence; D018556:Crops, Agricultural; D005260:Female; D020062:Heteroptera / Q000235:genetics / Q000502:physiology*; D059014:High-Throughput Nucleotide Sequencing; D018545:Lactuca / Q000469:parasitology*; D008297:Male; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000469:parasitology*; D060888:Real-Time Polymerase Chain Reaction; D012621:Seasons; D017422:Sequence Analysis, DNA; D061149:Thysanoptera / Q000235:genetics / Q000502:physiology*
keywords: Orius; conventional PCR; gut-content analysis; high-throughput sequencing; real-time PCR; trophic relationships