Evaluation of gas exchanges and production of genotypes of maçã banana type cultivated in the semi-arid region of Bahia

Abstract The objective of this study was to evaluate gas exchange and production of Maçã bananas type, at different times of the year and the day in semi-arid environment. Seven genotypes genotypes were used: Maçã, Caipira, BRS Tropical, BRS Princesa, YB42-03, YB42-17 and YB42-47, arranged in a completely randomized experimental design with five replicates and four useful plants per plot. For the physiological characteristics, a factorial arrangement 7x7x2 was considered (seven genotypes, seven evaluation periods, two reading times, 8:00 a.m. and 2:00 p.m.). Photosynthetic rates, carboxylation efficiency, and instantaneous water use efficiency are higher at 8:00 a.m., due to meteorological conditions, while foliar temperature and transpiration are higher at 2:00 p.m., due to the elevation of air temperature and low humidity. Months with higher radiation and intermediate temperature provided higher rates of photosynthesis, higher efficiency of carboxylation and photochemistry of photosynthesis. In general, genotype YB42-47 was the most productive, with higher water use efficiency and photosynthesis rates.

摘要 本研究旨在评估半干旱环境中不同季节与日内时段下苹果香蕉（Maçã Banana）的气体交换特性与产量表现。试验共选用7个基因型材料：苹果香蕉、卡皮拉（Caipira）、BRS Tropical、BRS Princesa、YB42-03、YB42-17及YB42-47，采用完全随机试验设计，设置5次重复，每小区定植4株有效植株。生理指标采用7×7×2析因设计开展测定，涵盖7个基因型、7个评估周期与2个测定时段（上午8:00与下午2:00）。结果表明，受气象条件影响，上午8:00时的光合速率、羧化效率与瞬时水分利用效率均高于下午时段；而下午2:00时因气温升高、空气湿度降低，叶温与蒸腾速率更高。辐射强度较高且温度适中的月份，可使光合速率、羧化效率及光合作用光化学效率维持在较高水平。总体而言，基因型YB42-47的产量表现最优，同时具备更高的瞬时水分利用效率与光合速率。