Growth, yield and gas exchanges of ‘D’Angola’ plantain under different plant densities

ABSTRACT Information about production, crop systems and economic viability for technical grown of plantain are scarce in Brazil. Few technologies developed specifically for plantain are available; thus, there are many adaptations of information on banana crops extrapolated to plantain. The objective of this study was to evaluate the growth, nutritional status, gas exchanges, water use efficiency and yield of ‘D’Angola’ plantain under different plant densities, in the first production cycle. The treatments consisted of six plant densities (1,111; 2,500; 2,777; 3,125; 3,571; and 4,166 plants ha-1), which were evaluated in a randomized block design with four repetitions. Vegetative growth, leaf nutrient concentrations at the flowering stage, gas exchanges (monthly) at two reading times, fruit yield and water use efficiency at harvest were evaluated. The nutritional status is not dependent on plant density. The vegetative growth varied, regardless of the plant density, whereas the leaf area index increased as the plant density was increased. The leaf temperature increased as the plant density was increased. The water use efficiency for fruit yield, as a function of plant density, fitted to a quadratic model, with the maximum value at 3,301 plants ha-1. The use of 3,333 plants ha-1 is recommended for plantain.

摘要：巴西境内有关大蕉（plantain）的生产栽培、种植系统及经济可行性的技术资料较为匮乏。目前专门针对大蕉开发的可用技术寥寥无几，因此诸多针对香蕉栽培的研究资料常被直接外推应用于大蕉种植。本研究旨在评估首个生产周期内，不同种植密度下‘D’Angola’大蕉的生长状况、营养状态、气体交换参数、水分利用效率及果实产量。试验设置6种种植密度（1111、2500、2777、3125、3571及4166 株·公顷⁻¹），采用随机区组设计，设置4次重复。试验测定指标包括营养生长状况、开花期叶片养分浓度、两个测定时段下的月度气体交换参数、收获期果实产量及水分利用效率。研究结果显示，大蕉的营养状态与种植密度无显著关联；无论种植密度如何，营养生长均存在差异，而叶面积指数则随种植密度提升呈上升趋势。叶片温度亦随种植密度提升而升高。果实产量的水分利用效率与种植密度的关系符合二次模型，其峰值出现在3301株·公顷⁻¹的种植密度下。生产中推荐采用3333株·公顷⁻¹的种植密度用于大蕉栽培。