Relationship Between Leaf Color and Pest Occurrence of Tobacco

The relationship between tobacco leaf color and the occurrence of pests was investigated for the purpose of effective pest control in tobacco field, the occurrence of several major pests on cv. Burley21 and cv Maryland609 in field were observed. The results indicated that no pest was found both on Burley21 and. Maryland609 until fast growing stage. Starting from that, Bemisia tabaci Gennadius and Myzus persicae Sulzer developed more rapidly on Burley21 than on Maryland609. The damage rates of Bemisia tabaci Gennadius on Burley21 were 17.16%, 30.97% and 40.02% at fast growing, flower-bud appearing and mature stages, respectively; in contrast to 0, 9.22% and 8.12% on Maryland609. The damage rates of Myzus persicae Sulzer on Burley21 were 18.23%, 29.09% and 31.15% in those stages, respectively; while they were 0, 8.37% and 10.31% on Maryland609. On the contrary, the damage rates of Heliothis assulta Quenee on Burley21 were 0, 9.52% and 21.22% at fast growing, flower-bud appearing and mature stages, respectively; while they were 22.16%, 37.14% and 41.18%, respectively, on Maryland609.