Chapter 1. Soil samples: strategies for sample collection, handling and storage

SAMPIETRO, D.A.; SOBERÓN , J.R.; SGARIGILA, M.A.; VATTUONE, M.A.

Soil Allelochemicals

Studium Press LLC

Lugar: Houston; Año: 2011; p. 3 - 24

Chemical interactions among organisms are central to understand any ecosystem. These interactions involve compounds named secondary metabolites, which are not strictly needed for the survival and reproduction of their producers (Harborne and Daey 1997). Allelochemicals are a group of secondary metabolites which participate in chemical interactions among organisms. In plant-plant interactions, these compounds are released from a donor plant, inhibiting or stimulating the growth and/or development of a neighboring one (Sampietro and Vattuone, 2006). Most allelochemicals are released into the soil environment. They are incorporated by leaching from aerial parts of donor plants, decomposition of their dead residues or root exudation. Despite the essential role of soil allelochemicals in allelopathy, the vast majority of publications devoted to them have been oriented to structural elucidation, at best accompanied by bioassays often providing little or absent knowledge about their real function in nature (Dayan and Duke, 2009). In fact, several phytotoxins are suspected allelochemicals, but in few cases the allelochemical role has been confirmed. This situation is due to the lack in comprenhension of the qualitative and quantitative dynamics of allelochemicals in the edaphic environment, specially in the rhizospheres of both donor and receptor plants (Weidenhamer, 2005). Sampling soil allelochemicals is an important step in this regard. It consists of obtaining representative samples of these compounds using adequate sampling techniques, as per sample nature and the purpose of chemical analysis (Moldoveanu and David, 2002). In this chapter, we provide general protocols and criteria applied to sampling, collection and storage of soil allelochemicals.