Abstract:

Based on tea picking date and meteorological data from three main tea producing areas in Hubei province from 2010 to 2022, significance analysis and correlation analysis methods was used to explore the impact of meteorological conditions on tea picking date. A prediction model of tea picking date for first round tea, second round tea, and third round tea was established, basing on meteorological factors. The results showed that: (1) the first, second and third round of tea in Hubei province entered the pluck starting date on March 30^th, May 17^th and June 27^th, respectively. There was a delayed trend with interannual variation. (2) The average temperature during the growing period of the first round of tea was Xian'an＞Yingshan＞Yiling. In mid−March, the average temperature remained stable at 10℃, and the tea tree's nutrient buds went through winter dormancy, accumulating a lot of nutrients. The spring shoots sprouted, reaching the conditions for the first round of tea picking. The average temperature during the growth period of the second round of tea was around 20℃. The average temperature during the growth period of third round of tea was around 25℃. The precipitation was almost above 100mm per month. The relative humidity was between 70%−85%. The sunshine hours were within a certain range. These conditions met the growth and development of tea trees. The first round of tea picking in Yiling was easily affected by spring frost. The picking date of Yingshan and Xian'an second and third round tea was greatly affected by heavy rainfall during the plum rain period. (3) The multiple linear regression model was used to predict the picking date of tea, and the historical data were used for verification. The results showed that the model had a prediction error of about 4 days for the first round of tea picking date, which was better than that of the second and third round of tea. At the same time, the accuracy of the model's forecasting time increased as the picking date approaches. Due to the impact of rare high temperatures and droughts in 2022, the model's predictive performance in the second and third round of tea picking date was poor. 

Key words: Three round tea, Picking date, Key meteorological elements, Multiple linear regression model, Hubei province