Seasonality in nutrient content of banana diagnostic leaf

Abstract Banana farming has an important position in Brazilian agricultural production. This position was earned due to the use of cultivation technologies and adequate fertilization made through recommendations of evaluation of foliar analyzes. The objective of this study was to determine the seasonality of the nutritional status of the diagnostic leaf during the development of banana tree. The experiments took place in the city of Sete Barras / SP, with cultivars such as Grande naine and Prata, on summer and winter. It was evaluated the influence of the collection of the diagnostic leaf in the stations, in six seasons during the development of the banana bunch and it was compared with the standard sampling. The values were submitted to analysis of variance, and when the F was significant, a comparison of means was performed. The sampling stations and the collection stages influence the nutrient behavior in the diagnostic leaf of both varieties, with exceptions for Mg and Mn. The average levels of nutrients during the collection stages showed no difference among the 1st, 2nd, 3rd and 4th (standard). Even for the ‘Prata’ and Grande Naine banana plants cultivated in the Ribeira Valley, there is no significant alteration in the nutrient content of the foliage among the 1st to 4th stages, allowing an increasing of collection for foliar tissue analysis.

摘要：香蕉种植业在巴西农业生产中占据重要地位，该地位的取得有赖于栽培技术的应用以及基于叶片分析评估建议所实施的精准施肥。本研究旨在明确香蕉树生长发育过程中诊断叶（diagnostic leaf）营养状况的季节变化特征。本实验于巴西圣保罗州塞特巴拉斯市（Sete Barras/SP）开展，供试品种为格南奈（Grande Naine）与普拉塔（Prata）香蕉，实验分别在夏季与冬季进行。研究在香蕉果穗发育的6个时期内，评估了采样时期对诊断叶采集的影响，并将结果与标准采样方案进行对比。对测得数据进行方差分析，当F检验达到显著水平时，进一步开展均值多重比较。结果表明，采样时期与采集阶段对两个供试品种诊断叶的养分动态均存在显著影响，但镁（Mg）与锰（Mn）除外。各采集阶段的养分平均含量显示，第1、2、3阶段与作为标准的第4阶段之间无显著差异。即便对于种植于里贝拉谷（Ribeira Valley）的普拉塔与格南奈香蕉植株而言，第1至第4阶段的叶片养分含量亦无显著变化，这为叶片组织分析的采样时机放宽提供了可行依据。