EFFECT OF USING ORGANIC FERTILIZERS ON THE PRODUCTIVE PARAMETERS OF TOMATOES UNDER FIELD METEOROLOGICAL CONDITIONS

In times of climate changes and increased demand for food purity a significant part of scientific research is directly addressed organic agriculture. The producers are increasingly orienting themselves to bio-production due to its longrun positive consequences both for human and environmental health. The role of organic production is clearly outlined in a number of papers and documents, related to the fight against climatic changes and soil and water contamination. This paper aims at answering the question of whether the biologically grown tomato variety Rugby presents a good alternative to the conventionally produced varieties with respect to their yield. The meteorological conditions during the vegetation period in 2021 have been analyzed in detail and basic productive parameters of the experimentally grown plants (number of standards and non-standard fruits; total weight in kg/da) have been compared for the two methods and three planting dates. At the first harvest in early summer, plants fertilized with mineral fertilizers NPK give better yields than unfertilized and fertilized with Arkobaleno. However, with the intensification of the unfavourable hydrothermal conditions by the end of the summer, the final total yield from the bio-fertilized plants for all the three planting dates already has better parameters not only compared to the unfertilized plants but also compared to the these grown after mineral fertilization. Biologically fertilized tomato plants show better productivity under conditions of over-wetting. Mineral fertilizers have a slight advantage in case of heat stress but the yields are comparable with those, from the plants, fed with the organic fertilizer Arkobaleno.