Microbiological contaminants in cabbage (Brassica oleraceae L.) production systems that apply good agricultural practices

Abstract

Cabbage (Brassica oleraceae L.), due to its characteristics, consumption method, and because it is part of the Nicaraguan population's diet, must be free of contaminating microorganisms that pose a risk to human health. The objective of this research is to determine the presence of contaminating microorganisms in the soil, plant tissue, and water sources used for irrigation in production systems that employ good agricultural practices and are in the municipality of Jinotega, in northern Nicaragua. The study period was from December 2024 to January 2025. Ten production systems were selected, where soil, water, and cabbage tissue samples were collected. The samples were transferred to the microbiology laboratory of the National Agrarian University for analysis. Mesophilic aerobes, total coliforms, and fecal coliforms were quantified, as well as the presence of fungi and bacteria, using the Most Probable Number and Colony Forming Units method. The presence of fungi and bacteria was diverse; the presence of Salmonella was found in the cabbage tissue in a single sample (10 % of the farms). Seven genera of bacteria and six genera of fungi were identified in the tissue, of which Bacillus sp and Pseudomonas sp. were predominant, and among the fungi, Fusarium sp. and Colletotrichum sp. The main source of microbiological contamination is associated with the use of water for irrigation, with the presence of total and fecal coliforms, represented by Escherichia coli. Eight production systems were found to have high microbial loads of total and fecal coliforms, so the implementation of good agricultural practices should be reviewed through a risk analysis, designing of an improvement plan and the application of an action plan.