Effects of Vermicompost Leachate versus Inorganic Fertilizer on Morphology and Microbial Traits in the Early Development Growth Stage in Mint (Mentha spicata L.) And Rosemary (Rosmarinus officinalis L.) Plants under Closed Hydroponic System

Abstract

The objective of this study was to compare the morphology of M. spicata and R. officinalis plants, and the relative abundance quantification, colony-forming units, ribotypes, and biofilm former bacteria under an inorganic fertilizer and the use of vermicompost leachate in the rhizosphere under a closed hydroponic system. In mint (Mentha spicata) plants treated with the vermicompost leachate, growth increase was determined mainly in root length from an average of 38 cm in plants under inorganic fertilizer to 74 cm under vermicompost leachate. In rosemary (Rosmarinus officinalis), no changes were determined between the two treatments. There were differences in the compositions of microbial communities: For R. officinalis, eight ribotypes were identified, seven for inorganic fertilizer and four for vermicompost leachate. For M. spicata, eight ribotypes were identified, three of them exclusive to vermicompost leachate. However, no changes were observed in microbial communities between the two treatments. Otherwise, some changes were observed in the compositions of these communities over time. In both cases, the main found phylum was Firmicutes, with 60% for R. officinalis and 80% for M. spicata represented by the Bacillus genus. In conclusion, the use of vermicompost leachate under the hydroponic system is a viable alternative to achieve an increase in the production of M. spicata, and for both plants (mint and rosemary), the quality of the product and the microbial communities that inhabited them remained unaltered.

The Impact of Food Waste Compost, Vermicompost, and Chemical Fertilizers on the Growth Measurement of Red Radish (Raphanus sativus): A Sustainability Perspective in the United Arab Emirates

“…A study carried out by Loera-Muro et al (2021) [ 53 ] examined the morphology, precisely root length, and microbial traits during the initial growth stage of mint and rosemary plants. The research aimed to cultivate lettuce using vermicompost and thermophilic compost.…”

Optimising Soilless Culture Systems and Alternative Growing Media to Current Used Materials

“…Moreover, Loera-Muro et al [7] recommended using vermicompost leachate fertiliser as a feasible replacement for inorganic fertiliser in hydroponic systems to achieve sustainable and eco-friendly agricultural production. The use of vermicompost leachate allows the maintenance of rosemary (Rosmarinus officinalis L.) or the increase in the production of mint (Mentha spicata L.) and with neither the modification of the bacterial communities for both plants nor changes to their ability to form biofilms.…”

“…Certification to the USDA organic standards is currently allowed if it is certifying to comply with the NOSB recommendations. However, which hydroponic practices align or do not align with the Organic Foods Production Act and USDA organic regulations is the subject of intense debate [5][6][7].…”

Chemical composition and biological properties in Mentha spicata under conventional and organic fertilization

“…In Iran, fertilization with a combination of 25% urea (23,75kg N ha -1 ) and 75% vermicompost (10,1t ha -1 ) significantly increased the number of leaves and the yield of essential oils in M. arvensis and M. piperitha (Keshavarz et al, 2018). Loera-Muro et al (2021) proposed the substitution of inorganic fertilizers by vermicompost leachates in hydroponic crops of Mentha spicata and Rosmarinus officinalis. Their study demonstrated that such organic fertilizer doubled root biomass production in both species.…”