Ownership rights do not provide the owner with full freedom of use over the owned thing anymore, especially when it comes to such valuable resources as agricultural land. Ownership rigths are privilegia odiosa these days. Highest legal acts of several countries, as well as decisions of the Court of Justice of the European Union, stress the fact that it is not absolute and that it has a particular social function. The owner is obliged to use the land, and to do so in a conventional manner. Conventional should, with respect to logical reasoning, relate only to what has been accepted, by a broader community, as useful and reasonable. However, that is not always the case in modern world. Agriculture is considered conventional when it is directed towards intensive plant production, while making use of artificial fertilizers, growth hormones, pesticides, fungicides, insecticides, and other chemical products. In USA and some other countries, production of plants which have a DNA modified by use of techniques of genetic engineering (GMO), are treated under the same legal regime. On the other hand, traditional, organic agriculture is treated as an exception, and special, more restrictive rules are applied to it. Civilization obviously found itself in an absurd situation. Something for which it is undoubtedly clear that it is bad in many aspects, and long term unsustainable (conventional agriculture) is considered normal, something for which it is not known whether and to which extent it is harmful (GMO agriculture) is being tolerated, and something for which we confidently know that it is not harmful, or at least not as nearly as harmful as the previously mentioned is considered an exception (organic agriculture). The difference between GMO immissions and emissions from a certain property being allowed or prohibited, i.e. whether the owner of a particular property will be held responsible for disturbance and possible damage, as a result of contamination of the environment, is determined by the way the GM plant production is being treated (as conventional or not). Therefore, the first part of this paper is dedicated to determining what is considered conventional use, in comparative law. The second part is dedicated to immissions of genetically modified organisms. In certain countries, special rules on coexistence of different types of agricultural production have been created, in order to prevent immissions, or bring them to a minimum. In Serbia, production of GM plants is prohibited. However, contamination of environment can come as a result of act with disrespect to the prohibition, by an owner or user of agricultural land. That opens an array of questions, to which traditional institutes of civil law are not capable of giving complete and precise answers.