The properties of rice hull in soilless agriculture technique and the effect of plant development parameters in lettuce (Lactuca sativa var. crispa) cultivation

Abstract

The properties of media used in soilless agriculture technique in plant production affect plant development directly. Media have different properties in order to provide support for the plant in the root part, and also are influential on root development, as well as its water and nutrients intake. Peat, coco-peat and perlite media are the most commonly used materials in the world. However, the high cost of peat aggregate and the limited peat reserve led to the need for seeking alternative media. Rice hull, which will be one of these alternative media, is a material that comes off during rice processing and poses an environmental problem in the form of waste management. Nowadays, minimizing the rice hull waste management problem on the environmental level gains even more importance especially in sustainable agricultural system. Therefore, the evaluation of rice hull, which is considered a renewable source of energy, in the soilless agriculture system has gained great importance. This material can be used not only without being processed but also in ground and carbonized forms. Available studies on the potential of using rice hull as an aggregate are not adequate. In this study, in addition to using peat, coco-peat and perlite media which are commonly used in soilless agriculture, we used fresh, ground and carbonized rice hull in lettuce cultivation. Bulk density (g cm(‑3)), aeration capacity (%), easily available water (%), water buffering capacity (%), porosity (%), moisture (%), organic matter (%), pH and electrical conductivity values were determined in six different media. In addition to this, by cultivating lettuce in soilless mediums, some vegetal data were also collected. Our results showed that rice hull waste can be used as an aggregate. Therefore further studies are needed to overcome the deficiencies on this subject.