Zapata D, Salazar M, Chaves B, Keller M, Hoogenboom G
AgWeatherNet, Washington State University, 24106 North Bunn Road, Prosser, WA, 99350, USA.
Department of Horticulture, Irrigated Agriculture Research and Extension Center, Washington State University, Prosser, WA, 99350, USA.
Int J Biometeorol. 2015 Dec;59(12):1771-81. doi: 10.1007/s00484-015-0985-y. Epub 2015 Apr 23.
Thermal time models have been used to predict the development of many different species, including grapevine (Vitis vinifera L.). These models normally assume that there is a linear relationship between temperature and plant development. The goal of this study was to estimate the base temperature and duration in terms of thermal time for predicting veraison for four grapevine cultivars. Historical phenological data for four cultivars that were collected in the Pacific Northwest were used to develop the thermal time model. Base temperatures (T b) of 0 and 10 °C and the best estimated T b using three different methods were evaluated for predicting veraison in grapevine. Thermal time requirements for each individual cultivar were evaluated through analysis of variance, and means were compared using the Fisher's test. The methods that were applied to estimate T b for the development of wine grapes included the least standard deviation in heat units, the regression coefficient, and the development rate method. The estimated T b varied among methods and cultivars. The development rate method provided the lowest T b values for all cultivars. For the three methods, Chardonnay had the lowest T b ranging from 8.7 to 10.7 °C, while the highest T b values were obtained for Riesling and Cabernet Sauvignon with 11.8 and 12.8 °C, respectively. Thermal time also differed among cultivars, when either the fixed or estimated T b was used. Predictions of the beginning of ripening with the estimated temperature resulted in the lowest variation in real days when compared with predictions using T b = 0 or 10 °C, regardless of the method that was used to estimate the T b.
热时间模型已被用于预测许多不同物种的发育情况，包括葡萄（欧亚种葡萄）。这些模型通常假定温度与植物发育之间存在线性关系。本研究的目的是估计基础温度和热时间持续时间，以预测四个葡萄品种的转色期。利用在太平洋西北地区收集的四个品种的历史物候数据来建立热时间模型。评估了0℃和10℃的基础温度以及使用三种不同方法得到的最佳估计基础温度，以预测葡萄的转色期。通过方差分析评估每个品种的热时间需求，并使用Fisher检验比较均值。用于估计酿酒葡萄发育基础温度的方法包括热量单位中的最小标准差、回归系数和发育速率法。估计的基础温度因方法和品种而异。发育速率法为所有品种提供了最低的基础温度值。对于这三种方法，霞多丽的基础温度最低，在8.7至10.7℃之间，而雷司令和赤霞珠的基础温度最高，分别为11.8℃和12.8℃。无论使用固定的还是估计的基础温度，不同品种的热时间也存在差异。与使用基础温度T b = 0或10℃的预测相比，使用估计温度预测成熟开始时实际天数的变化最小，无论用于估计基础温度的方法如何。
