Antioxidant in relation to nutrition, stomata, and yield of lettuce (Lactuca sativa L.) fertilized with seabird guano

Cruz Nietoa D.D.; Castañeda Chirre E.T.; Mamani Salcedo B.L.; De Liendo F.V.P.N.V.; Romero Menacho J.U.; Cabanillas Sulca J.C.; Condori Ramos G.M.; Vilca Arratia P.E.; Castañeda Samanamu M.A.; Torres Calderon A.F.; Alvarez Quinteros C.P.; Luperdi Rios F.V.; Lacherre Rodriguez G.P.; Ramos Vera J.R.; Chirito Laurencio C.A.; Cruz Nieto A.E. · Brazilian Journal of Biology (2026) · DOI: 10.1590/1519-6984.303591

Resumen

Peru faces a complex economic crisis, exacerbated by persistent food and nutritional insecurity as a result of the pandemic, geopolitical tensions, adverse weather conditions, and other relevant factors. For this reason, an investigation was conducted on antioxidants in relation to nutrition, stomata, and the yield of lettuce fertilized with seabird guano (S.G.). The general objective was to determine the antioxidant capacity in relation to nutrition, stomata, and yield of lettuce fertilized with S.G. The methodology is based on applied research with an experimental approach, as the statistical model of the completely randomized block design was employed, consisting of three blocks and five treatments: T1 with 0, T2 with 300, T3 with 600, T4 with 900, and T5 with 1,200 kg ha-1 of S.G. The doses were applied 15 days after transplanting, and the physical characteristics (plant height, plant weight, commercial yield, and plant diameter) were evaluated. Nutrients (nitrogen, potassium, phosphorus, calcium, magnesium, sulfur, molybdenum, iron, manganese, copper, zinc, boron, chlorides, and sodium), antioxidant capacity, and stomatal density in the leaves were determined. Also, total phosphorus and nitrogen uptake and profitability. The results showed that T5 stood out in plant height at 25 cm, plant weight at 618.8 g, commercial yield at 61.501 t ha-1, and diameter at 15.91 cm. In total nitrogen consumption, it stood out with 174.68 kg ha-1, and in total phosphorus consumption with 180.77 kg ha-1. In stomatal density, it stood out with 134 stomata/mm2 and in profitability with 443.5%. In leaf nutrient concentration, T2 stood out with calcium, magnesium, sulfur, molybdenum, boron, and sodium, and T3 excelled in antioxidant capacity with 4,607.8 μmol Trolox/100 g. It is concluded that an adequate antioxidant capacity (4,020.0 μmol Trolox/100 g in T5) was associated with the highest lettuce yield. Therefore, at higher doses of S.G., stomatal density and nutrients such as nitrogen, phosphorus, copper, and chlorides in the leaves increased, which enhanced the efficiency of gas and nutrient exchange. These characteristics optimized physiological processes and modulated antioxidant pathways, thereby improving yield.

Instituciones: Universidad Nacional José Faustino Sánchez Carrión; Universidad Nacional Autónoma de Huanta; Universidad Nacional de Educación Enrique Guzmán y Valle