Influence of organic matter management on the activity and structure of soil microbial community in intensive tomato (Solanum lycopersicum L.) greenhouse farming

Aim of study: Intensive agriculture impacts physical, chemical, and biological characteristics of soil; therefore, the addition of organic matter (OM) to soil can have significant implications for crop production. This study investigated the impact of three crop management systems on tomato production and soil microbial communities in intensive greenhouse farming. Area of study: Province of Almería (Spain). Material and methods: The three crop management systems included: (1) conventional management, using synthetic chemical fertilizers without OM application (CM); (2) conventional management, using synthetic chemical fertilizers with at least one OM application in the last three years (CMOM); and (3) fully organic management, featuring yearly OM applications and no use of synthetic chemical fertilizers (ORG). Main results: Compared to CM soils, OM addition in CMOM and ORG led to higher soil NO3- and NH4+ content, which in turn increased nitrogen (N) availability, leading to an increase in soil respiration. The addition of OM also altered the composition of prokaryotic and fungal soil communities. Besides, the addition of OM reduced the presence and abundance of potential fungal pathogenic organisms, like Sclerotinia sp. and Plectosphaerella cucumerina. OM addition to conventionally managed greenhouses (CMOM) led to higher crop yields compared to CM greenhouses, resulting in an overall increase of 880 g m-2. Production under fully organic management (ORG) was lowest, possibly due to the nutrient and pest management practices used. Research highlights: Our data show the importance of organic matter management in shaping microbial communities in intensive greenhouse systems, which can be a key factor in developing a more sustainable agriculture to feed a growing human population.