Alyssum flowers promote biological control of collard pests
Collard greens Brassica oleracea (L.) are often attacked by various pests including whiteflies, aphids and diamondback moth. Hitherto, the main method used to manage these pests in Brazil has been the application of a limited number of registered insecticides. The search for more sustainable pest management strategies is therefore warranted. In this context, the conservation biological control stands out as an appealing alternative. Conservation biological control is achieved, at least in part, by strip-cultivating and/or conserving flowering plants within the agroecosystem. The present study investigates how alyssum flowers Lobularia maritima (L.) could contribute to the attraction of natural enemies and to the management of collard pests. Two field experiments were conducted in different years. Each experiment consisted of two treatments and three replicates, which were set up in a completely randomized design. The treatments were (1) collards alone, and (2) collards + alyssum. We evaluated weekly the population density of natural enemies and pests on both treatments. The results show that the alyssum flowers attractiveness contributed to increase the abundance of generalist predators during both experiments, which in turn translated into a significant reduction of collards pests, especially aphids. Some of the main predators attracted/harbored by alyssum flowers were spiders, coccinellids, syrphids and Orius sp. Finally, strip intercropping alyssum with collards can be an important strategy to manage brassica pests and cope with the limited availability of insecticides registered for this vegetable crop.
KeywordsConservation biological control Lobularia maritima Brassicas Intercropping
We would like to thank Ênio Basilio, Lucas Ferreira Neto, Marta Ribeiro and Robson da Silva for helping with the experiment setup and some of the data collection.
- Chaney WE (1998) Biological control of aphids in lettuce using in-field insectaries. In: Pickett CH, Bugg RL (eds) Enhancing biological control: habitat management to promote natural enemies of arthropod pests. University of California Press, Berkeley, pp 73–83Google Scholar
- Firake DM, Lytan D, Behere GT (2012) Bio-diversity and seasonal activity of arthropod fauna in brassicaceous crop ecosystems of Meghalaya, north east India. Mol Entomol 3(4):18–22Google Scholar
- Gontijo LM (2011) Integrated biological control of woolly apple aphid in Washington State. PhD dissertation, Washington State University, Pullman, USAGoogle Scholar
- Gurr G, Wratten SD, Alteri MA (2004) Ecological engineering for pest management: advances in habitat manipulation for arthropods. CSIRO Publishing, CanberraGoogle Scholar
- Patt JM, Hamilton GC, Lashomb JH (1997) Impact of strip-insectary intercropping with flowers on conservation biological control of the Colorado potato beetle. Adv Hortic Sci 11:175–181Google Scholar