Agronomic characteristics and quality of lettuce cultivars in different crop seasons in western Alagoas, Brazil

ABSTRACT Growing lettuce under high temperatures and light incidence, as in the Alagoas State hinterland, Brazil, induces early tasseling and decreases the quality of the product. Thus, the objective of this work was to evaluate the production and post-harvest quality of lettuce cultivars in different crop seasons in western Alagoas, Brazil. A randomized block experimental design was used, with four replications. The treatments consisted of lettuce cultivars: Baba-de-Verão, Cinderela, Elba, Mônica, Solaris, and Veneranda. The winter crop was more favorable for plant diameter, except for Baba-de-Verão, whose performance was similar in both seasons and stood out in the summer. The winter crop resulted in better performance in plant height, stem diameter, and fresh matter yield, whereas summer plants reached larger number of leaves. The cultivar Mônica presented longer stem length, denoting lower tolerance to early tasseling and, therefore, it is not indicated to be grown in the region. The cultivar Baba-de-Verão (Lisa group) reached higher fresh matter yield, number of leaves per plant, and stem diameter, and it was the most adequate cultivar to be grown in western Alagoas. Elba, Solaris, and Veneranda were the lettuce cultivars from the Crespa group that stood out. Baba-de-Verão was the cultivar that presented the best performance for chlorophyll a, b, and total. The cultivar Solaris presented the highest carotenoid contents. Plants grown in the winter reached higher chlorophyll a and total, carotenoid contents, pH, and soluble solid (SS) to titratable acidity (TA) ratio, whereas the lettuce grown in the summer had higher SS and TA.

摘要：在巴西阿拉戈斯州内陆等高温强光照环境下种植生菜，易诱导植株过早抽薹，降低产品品质。为此，本试验旨在评估巴西阿拉戈斯州西部地区不同种植季下各生菜品种的产量与采后品质（post-harvest quality）。试验采用随机区组实验设计（randomized block experimental design），设置4次重复，供试品种包括Baba-de-Verão、Cinderela、Elba、Mônica、Solaris及Veneranda。冬季种植更利于提升植株直径，但Baba-de-Verão品种除外：该品种在两个种植季的表现相近，且夏季种植时表现更突出。冬季种植的植株在株高、茎粗及鲜物质产量（fresh matter yield）上表现更优，而夏季种植的植株单株叶片数更多。Mônica品种茎长更长，表明其对早抽薹（early tasseling）的耐受性更低，因此不适宜在本地区种植。Baba-de-Verão（Lisa组）的鲜物质产量、单株叶片数及茎粗均为最优，是最适宜在阿拉戈斯州西部地区种植的生菜品种。Elba、Solaris与Veneranda均为表现突出的Crespa组生菜品种。Baba-de-Verão品种的叶绿素a、叶绿素b及总叶绿素含量表现最佳；Solaris品种的类胡萝卜素含量最高。冬季种植的生菜植株具有更高的叶绿素a、总叶绿素、类胡萝卜素含量，以及更高的pH值与可溶性固形物（soluble solid, SS）与可滴定酸度（titratable acidity, TA）比值；而夏季种植的生菜则拥有更高的SS及TA含量。