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Agricultural Biodiversity and Plant Defense: The Potential of Varietal Mixtures for Insect Pest Management

November 23rd, 2014 | Source: Eleni Kapsomenou 1*, Joop J.A. van Loon 1 & Devra I. Jarvis 2

Photo 15-11-14 09 59 49  Crop monocultures-the challenge:

a prevailing global change of the 20st Century
advantage: uniformity in harvest maturity & mechanization of agricultural operations
disadvantage: uniform susceptibility to insect pests and plant pathogens

Hypothetically in a varietal mixture:
Stronger attraction and higher diversity of natural enemies
Enhanced pest suppression by natural enemies
Stronger direct repulsion of pests by plants
Increased crop productivity
Promising but limited research evidence:
Significant differences (qualitative and quantitative) were found in volatile emission between varieties in many crops e.g. cucumber, rice, cotton and apple.
Mixture of barley varieties was preferred by predatory ladybird beetle over pure stands and showed increased aphid control
Primary parasitoids were more diverse in mixtures of common perennial grass varieties which led to enhanced aphid control. See the poster for more details ELLS Poster_Eleni Kapsomenou