Plant growth-promoting bacteria as affected by N availability as a suitable strategy to enhance the nutritional composition of lamb's lettuce affected by global warming

• Published in: Food chemistry 2023-11, Vol.426, p.136559-136559, Article 136559
• Main Authors: Collado-González, Jacinta, Carmen Piñero, María, Otalora, Ginés, Lopez-Marín, Josefa, del Amor, Francisco M.
• Format: Article
• Language: English
• Subjects: Bacteria - genetics; Bacteria - metabolism; Bioactive compounds; Climate change; Global Warming; Heat-Shock Response; Humans; Lamb’s lettuce; Nitrates - metabolism; Nitrogen levels; Plant growth promoting bacteria; Reduction of nitrate; Valerianella
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2023.136559

•Healthier Lamb’s lettuces by the application of this novel practice.•The adequate supply of nitrogen increases the amino acids content.•A significant increase in the content of health-promoting compounds in Lamb’s lettuce with this novel practice.•A lower content of nitrates in Lamb’s lettuce after using this sustainable practice. Heat and nutritional stresses have a significantly effect on the accumulation of bioactive and other compounds harmful to human health, like nitrates, in green leafy vegetables like lamb’s lettuce. Plant growth-promoting bacteria (PGPB) have shown to confer beneficial biochemical changes to various crops under different stresses. The hypothesis proposed here is that the combination of optimal N level (2.5 Mm, 12 mM or 20 mM of N) with the inoculation of PGPB in plants exposed to heat shock (43 °C) may be a good strategy to obtain healthier lamb’s lettuce with a higher yield. Results showed that a dose of 20 mM N can be considered as overfertilization. Moreover, the inoculation of plants fed with fertilizers with reduced N and under heat stress, resulted in higher productivity and content of sugars (60 %), amino acids (94 %), nitrogen (21 %), and total phenolic compounds (30 %), and a reduced content of nitrates (27 %).