Study on integrated climatic index for low temperature injury of loquat in putian

Based on the daily climate data in winter and relative meteorological yield of loquat for 2 meteorological stations in Putian from 1992 to 2009, this paper studied the disaster-inducing factors and integrated climatic index for low temperature injury of loquat. The results showed that the critical temperature for low temperature injury of loquat could be determined as 3.0 degrees C. The disaster-inducing factors included extreme minimum temperature, the sum of daily numbers for less than or equal to 3.0 degrees C, the sustained days of low temperature injury for less than or equal to 3.0 degrees C, and harmful chilling accumulation for less than or equal to 3.0 degrees C, and there were obvious correlations among these factors. According to the method of principal component analysis, an integrated climatic index was obtained. By the correlation analysis of integrated climatic index for low temperature injury and the relative meteorological yield of loquat in Putian, the value of integrated climatic index of low temperature injury was significantly negatively correlated with the yield of loquat, and could be used to analyze the degree of low temperature injury of loquat.