Cardinal temperatures and modeling of vegetative development in guava

ABSTRACT The aim of this study was to estimate cardinal temperatures (base, optimum, and maximum), and simulate the vegetative development of guava crop through phyllochron (linear) and Wang and Engel (nonlinear) models at the seedling phase. The experiment was conducted in Itajubá, MG, Brazil (22° 24’ 46.43” S 45° 26’ 48.94” W), for two years in a completely randomized design with twelve sowing dates and five experimental units per treatment, totaling sixty experimental units. The cardinal temperatures were estimated using twelve methods described in the literature and the values were: base, 10.9 °C, optimum, 17.3 °C and maximum, 51.2 °C. The phyllochron model was superior to Wang and Engel’s model for simulation of vegetative growth of guava, with root mean square error of 1.5 leaves.

摘要：本研究旨在估算番石榴（guava）实生苗阶段的基点温度（cardinal temperatures，包括最低、最适与最高温度），并分别通过叶间隔期（phyllochron，线性）模型与Wang和Engel（非线性）模型模拟其营养生长发育过程。试验于巴西米纳斯吉拉斯州伊塔茹巴（22°24′46.43″S，45°26′48.94″W）开展，为期两年，采用完全随机设计（completely randomized design），设置12个播期处理，每个处理设置5个试验单元，总计60个试验单元。本研究采用文献记载的12种方法估算基点温度，所得参数为：最低温度10.9℃，最适温度17.3℃，最高温度51.2℃。相较于Wang和Engel模型，叶间隔期模型对番石榴营养生长的模拟效果更优，其均方根误差（root mean square error）为1.5片叶。