Biostimulant alleviates abiotic stress of mango grown in semiarid environment/Bioestimulante alivia o estresse abiotico da mangueira cultivada em ambiente semiarido

The shoot maturation phase is important for growing mango tree because it precedes the floral induction, when plants are under stress caused by high temperatures and low water availability, that could be reduced by using plant biostimulant. Thus, the current study aimed to use a plant biostimulant containing yeast extract and amino acids to alleviate abiotic stress in mango plants, cv. Tommy Atkins, grown in semiarid environment. The experimental design consisted of randomized blocks with five treatments, five repetitions and five plants per plot. Treatments consisted of: T1) two foliar sprays with [biostimulant + KC1] + two foliar sprays with [K.sub.2]S[O.sub.4]; T2) No biostimulant and four foliar sprays with [K.sub.2]S[O.sub.4]; T3) three individual foliar sprays with biostimulant and one foliar spray with [K.sub.2]S[O.sub.4]; T4) two foliar sprays with biostimulant and two foliar sprays with [K.sub.2]S[O.sub.4]; and T5) two foliar sprays with [biostimulant + [K.sub.2]S[O.sub.4]] + one foliar spray with [K.sub.2]S[O.sub.4]. The variables evaluated were: i) leaf concentrations of soluble carbohydrates, starch, amino acids and proline; and ii) enzymatic activity of catalase and ascorbate peroxidase. The foliar spray with biostimulant during the branch maturation phase of mango trees grown in tropical semiarid environment alleviated plant abiotic stress. Three foliar biostimulant sprays and one [K.sub.2]S[O.sub.4] spray are recommended to alleviate mango plant abiotic stress in semiarid environment. Key words: Mangifera indica L., amino acids, enzyme activity, soluble carbohydrates, yeast extract A fase de maturacao de ramos e importante no cultivo de mangueira porque precede a inducao floral, quando as plantas estao sob estresse causado por elevadas temperaturas e baixa disponibilidade hidrica, que poderia ser amenizado pelo uso de bioestimulante. Assim, o presente estudo teve como objetivo utilizar um bioestimulante de plantas contendo extrato de levedura e aminoacidos na atenuacao do estresse abiotico em plantas de manga, cv. Tommy Atkins, em ambiente semiarido. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos, cinco repeticoes e cinco plantas por parcela. Os tratamentos consistiram de: T1) duas pulverizacoes foliares com [bioestimulante + KC1] + duas pulverizacoes foliares com [K.sub.2]S[O.sub.4]; T2) sem bioestimulante e quatro pulverizacoes foliares com [K.sub.2]S[O.sub.4]; T3) tres pulverizacoes foliares individuals com bioe