Evaluation of Organic Substrates and Microorganisms as Bio-Fertilisation Tool in Container Crop Production

Abstract

Microorganisms are only effective when adequate conditions for their survival and development are provided. Among the factors that influence its effectiveness includes the type of soil or culture substrate, which works as an energy source reserve. Therefore, a tomato and a melon crop were established in different cycles to assess the effect of the physicochemical properties of organic substrates based on coconut fibre and vermicompost in three proportions, 0:100, 40:60 and 60:40 (% v:v), on the microbial activity in the rhizosphere when the bacteria Azotobacter vinelandii, Bacillus megaterium and Frateuria aurantia were applied. Concentrations of NO3−, H2PO4−, K+ and Ca2+ in the petiole cellular extract (PCE) were quantified at 60, 90 and 120 days after transplantation (DAT) for tomato and 45 and 65 DAT for melon. We analysed dehydrogenase activity (DHA), acid phosphatase activity (FTA) and β-glucosidase activity (β-GLU). In order to maintain optimal volumetric moisture for the survival of microorganisms, automatic control was used to manage the irrigation frequency between 22%–28%. The results showed that physicochemical substrate properties, by incorporating 40% vermicompost into the coconut fibre mixture, increased enzymatic activity. Plants that were inoculated with Azotobacter vinelandii and Frateuria aurantia showed an improvement in NO3− and K+ assimilation achieving highest yields.

Different Organic Fertilisation Systems Modify Tomato Quality: An Opportunity for Circular Fertilisation in Intensive Horticulture

“…Except for lycopene, the higher presence of antioxidant compounds found in tomatoes treated with the highest dose of vermicompost (V9), with respect to the tomatoes treated with a 3 kg m −1 dose (V3), may be explained by the higher presence of microorganisms and an improvement in enzymatic activity when a higher dose of vermicompost is applied [56]. However, the differences in microbial activity are not completely related to the concentration of macronutrients in soil recorded in this study, and biological activity should be analysed [56] to understand the differences in results. PO 4 2− , N Kjeldahl, Mg 2+ and O.M.…”

“…Furthermore, vermicompost has the largest fraction of degraded organic matter compared with the other organic amendments, resulting in higher nutrient availability. The application of vermicompost can also enhance microbial activity in the soil, thus improving the N availability for plants [55,56]. However, a study by Mejia et al [28] in a soilless experiment demonstrated that higher doses of vermicompost lead to higher microbial activity, but the N concentration in the substrate does not increase.…”

Evaluation of substrates and additives to Trichoderma harzianum development by qPCR

“…The presence of cornmeal served Coniothyrium as a source of carbohydrates for optimal growth without affecting the development of the plant. In another study, substrates with high levels of organic matter as vermicompost or coconut fiber showed greater enzymatic activity of plant growth‐promoting bacteria present in them, such as Frateuria aurantia , among others (Ruiz et al., 2019).…”

“…The promoter effect of beneficial microorganism must be to an integral part of the biological cycle of nutrients, facilitating their availability for plants. It is necessary to characterize substrates to determine their ability to influence microbial activity which is a fundamental factor in maintaining sustainability and productivity (Fu et al., 2017; Ruiz, del, & Salas, 2019).…”

Bioinoculants—Natural Biological Resources for Sustainable Plant Production

“…[38]. Frateuria aurantia is another important KSB [131]. KSB dissolve silicate and release Kand these can be effective bioinoculants for the future.…”