Productivity of lettuce in greenhouse as affected by humic and fulvic acids application in association to mineral fertilizer

Ana Cristina Lüdtke,Vicente Kraemer,Luiza Morosino,Deborah P Dick

doi:10.1590/s0102-0536-20210414

Ana Cristina Lüdtke, Vicente Kraemer + Show 2 more

Open Access

https://doi.org/10.1590/s0102-0536-20210414

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Abstract

ABSTRACT Humic substances (HS) have proved to be effective in improving the productivity of vegetable crops. We examined the effect of commercial biostimulants rich in humic (HA) and fulvic acids (FA) obtained from leonardite on agronomic efficiency and nutrient content in the leaves of lettuce (Lactuca sativa). A greenhouse experiment was carried out employing 2.5-L pots containing Ultisol samples that were supplied with commercial biostimulants rich in HA and FA, alone and in combination with NPK mineral fertilizer. The application of HS biostimulants associated to mineral fertilization to the lettuce plants provided the greatest values of the studied variables, namely: plant height and diameter, leaf number per plant and root length. The combination of FA biostimulants and mineral fertilization increased the lettuce productivity relative to the inorganic fertilizer alone. The combined application of rich biostimulants FA and HA with NPK fertilizes influenced K and Fe uptake by the plants, and their accumulation in the aerial portion. Our results suggest that HS products potentialize the nutritional effect of the mineral fertilizer, when applied in combination.

Highlights

Produtividade da alface em resposta à aplicação de ácidos fúlvicos e ácidos húmicos associado a fertilizante mineral em casa de vegetação
We examined the influence of Humic substances (HS)-based biostimulants alone and in combination with a mineral fertilizer, applied directly to soil, on the productivity and nutrient content in the leaves of lettuce cultivated in greenhouse
For both number of leaves and plant diameter the values decreased in the order: Fulvic acids (FA)+NPK > NPK = Humic acids (HA)+NPK = HA=FA > Control

Summary

Introduction

Produtividade da alface em resposta à aplicação de ácidos fúlvicos e ácidos húmicos associado a fertilizante mineral em casa de vegetação. New strategies and technologies have been studied in order to improve the sustainability of agricultural ecosystems such as the application of HS-based products, called HS-biostimulants (García et al, 2018; Nardi et al, 2021), which can prevent and/or reduce the negative effects caused by excessive and continuous use of mineral fertilizer (Turan et al, 2021).

Results

Conclusion