Agronomic biofortification of waterleaf (Talinum triangulare) with zinc applied via root

Abstract Zinc (Zn) deficiency affects one-third of the world’s population, and agronomic biofortification is a good way to fight against this problem. Biofortification of leafy vegetables has been driven by their consumption, and, in this scenario, the waterleaf (Talinum triangulare) demonstrates good potential. Thus, this work aimed to verify the efficiency of agronomic biofortification of waterleaf with Zn applied via root. For the experiment, seedlings obtained with vegetative propagation by cuttings were used and cultivated in a mixture of sand and commercial substrate, initially in the laboratory. After acclimatization, the seedlings were transferred to a plant nursery, where NPK and Zn were applied, in six treatments (source Zinc Sulphate Heptahydrate, ZnSO4.7H2O), T1: control; T2: 12.5 mg kg-1; T3: 25 mg kg-1; T4: 50 mg kg-1; T5: 100 mg kg-1; T6: 400 mg kg-1. The length, number of leaves, shoots, inflorescences, and diameter of the collection were measured. The leaf dry mass (LDM), stem (SDM), root (RDM), root-shoot ratio (R S-1), leaf weight ratio (LWR), Dickson’s Quality Index (DQI), leaf and soil Zn levels, total proteins and soluble sugars (TSS) were analyzed. The dose of 400 mg kg-1 provided toxicity to plants, and the dose of 100 mg kg-1 demonstrated better results in plant growth and development and contents of proteins and zinc, with an increase of 4081% of Zn, indicating which is the most effective dose to be used in the biofortification of this species. Resumo A deficiência de Zinco (Zn) atinge um terço da população mundial, e a biofortificação agronômica é uma forma de combatê-la. A biofortificação de hortaliças folhosas tem sido impulsionada pelo seu consumo e, neste cenário, o cariru (Talinum triangulare) demonstra potencial para esses estudos. Assim, este trabalho teve como objetivo verificar a eficiência da biofortificação agronômica de cariru com Zn aplicado via radicular. Para o experimento, foram utilizadas mudas obtidas com a propagação vegetativa por estaquia, cultivadas em uma mistura de areia e substrato comercial inicialmente em laboratório. Após aclimatação, as mudas foram transferidas para um viveiro, onde foram aplicados NPK e Zn, em seis tratamentos (fonte Sulfato de Zinco Heptahidratado, ZnSO4.7H2O), T1: testemunha; T2: 12.5 mg kg-1; T3: 25 mg kg-1; T4: 50 mg kg-1; T5: 100 mg kg-1; T6: 400 mg kg-1. Foram medidos o comprimento, número de folhas, brotações, inflorescências e diâmetro da coleção. A massa seca da folha (LDM),