Behavioral responses of Toxoptera aurantii to green colors with different SPAD values
茶蚜对不同SPAD值绿色的趋性

This paper studied the behavioral responses of Toxoptera aurantii to green colors with different SPAD values produced by computer simulation,and to fresh tea leaves under different nitrogen supply.The results showed that T.aurantii at its different development stages had different responses to the SPAD values.There was a significant linear correlation between leaf nitrogen content and SPAD value.Young nymphs of T.aurantii preferred the green color with a corresponding leaf nitrogen content around 2.83%,while mature nymphs and apterous and pterous adults preferred that with the corresponding nitrogen content being 2.83%-3.14% and about 3.14%,respectively.As for the fresh leaves under different nitrogen supply,young nymphs preferred the leaves with 2.64%-3.13% nitrogen content,while mature nymphs and apterous and pterous adults preferred the leaves whose nitrogen content was 2.68%-2.83%,2.42%-2.84%,and 2.63%-3.13%,respectively.All of these suggested that T.aurantii at its different development stages had different demands on the nitrogen content of tea leaves,which provided a theoretical basis for the rational fertilization in tea garden,and the effective control and management of T.aurantii.