Possibilities of biological soil management in monoculture greenhouse cultivation: cover crops, organic matter replenishment and <i>Trichoderma</i> sp. application to improve soil health

Today, soil degradation processes present severe challenges to farmers. This is even more typical in cultivating vegetables in growing equipment, where the intensive use of chemicals causes physical, chemical, and biological degradation of soils. Therefore, it is essential to find solutions with which we can sustainably slow down these processes in such a way as to minimize crop losses and not increase the costs of growers. One such solution could be the use of cover crops in growing equipment. Our main objective was to find a sustainable cultivation solution to increase soil biological activity, organic matter and nutrient content, thus improving soil health. The research was carried out on sandy soil with low organic matter content in a foil housing experiment. Several soil samples were taken during the experimental period. The labile carbon content (POXC), fluorescein diacetate and phosphatase enzyme activity, nitrate content and yield tests were also determined from the soil samples. Based on our results, we could not detect a significant difference between the cover crop + <i>Trichoderma</i> treatment and the cover crop treatment. However, we found that when using cover crops, the <i>Trichoderma</i> treatment had a positive effect and was significantly different from the other treatments for biological activity (FDA), phosphatase activity, and nitrogen retention. Although there was no difference in yield between the treatments, the positive characteristics mentioned above may help develop a sustainable horticultural production that will improve soil health in the long term. Overall, it can be concluded that using cover crops can be an effective method for increasing the active carbon content of the soil, which microbes can use. Furthermore, with the diversity of its root system, the well-chosen cover plant mixture provides a vast, rich surface and a habitat for soil microbes, increasing biological activity. In addition, the rhizosphere, the scene of important metabolic processes, contributes significantly to increasing the soil's organic matter stock.