Gas exchange and post-harvest quality of ‘Kent’ mango subjected to controlled water deficit in semi-arid region

ABSTRACT Brazil is the seventh largest producer of mangoes in the world, and the São Francisco Valley is the main producing region, with ‘Kent’ as one of the main cultivars. Considering that irrigation management affects physiological events, production and fruit quality, the objective of this work was to evaluate the gas exchange in the leaves and fruit quality of ‘Kent’ mango subjected to controlled water deficit in the semi-arid region. The experiment was carried out in Petrolina-PE, semi-arid region of the São Francisco Valley. The experimental design used was randomized blocks, in a triple factorial scheme, with four irrigation depths (40, 60, 80 and 100% of crop evapotranspiration - ETc), three phenological stages (F1 - flowering, F2 - fruit growth, F3 - fruit maturation) and two production cycles (2018 and 2019), with four replicates. During the phenological stages, the physiological parameters of gas exchange were evaluated. After harvesting, the following parameters were evaluated: soluble solids content, titratable acidity, pH, firmness and peel color. Irrigation with a depth between 79.5 and 83.6% ETc during the evaluated stages promoted greater gas exchange in the leaves, greater firmness and acidity in the fruits. The reduction in irrigation depth in F1 and F3 reduced the soluble solids content, while in F2 the highest soluble solids content was obtained with irrigation between 68.24 and 74.5% ETc. The most suitable irrigation depth for ‘Kent’ mango cultivation depends on the purpose of the producer and on the phenological stage of the crop.

摘要 巴西为全球第七大芒果生产国，圣弗朗西斯科河谷（São Francisco Valley）是其核心芒果产区，‘肯特’（Kent）芒果为主要栽培品种之一。鉴于灌溉管理可影响作物生理活动、产量与果实品质，本研究旨在评估半干旱地区‘肯特’芒果在受控水分亏缺条件下的叶片气体交换与果实品质。本试验于圣弗朗西斯科河谷半干旱区域的佩特罗利纳-佩（Petrolina-PE）开展，采用随机区组设计（randomized blocks），设置三因子试验方案（triple factorial scheme），包含4个灌溉梯度（分别为作物蒸发蒸腾量（crop evapotranspiration, ETc）的40%、60%、80%、100%）、3个物候期（F1：开花期，F2：果实生长期，F3：果实成熟期）以及2个生产周期（2018年与2019年），各处理设置4次重复。试验期间，在各物候期内测定叶片气体交换相关生理参数；采收后，依次测定可溶性固形物含量、可滴定酸度、pH值、果实硬度及果皮色泽等指标。试验结果表明，在各测定物候期内采用79.5%~83.6% ETc的灌溉梯度，可显著提升叶片气体交换效率，同时改善果实硬度与酸度水平。在F1与F3期降低灌溉梯度会降低果实可溶性固形物含量，而在F2期采用68.24%~74.5% ETc的灌溉梯度时，可获得最高的可溶性固形物含量。综上，‘肯特’芒果栽培的适宜灌溉梯度取决于种植者的生产目标与作物所处的物候阶段。