Biology of the leafhopper, Zyginidia sohrab Zachvatkin, on corn under laboratory conditions
Çetin Mutlu, Erdal Sertkaya
The life history of Zygnidia sohrab Zachvatkin was studied on potted corn at three constant temperatures (20, 25, 30± 1 °C) under laboratory conditions. The incubation periods of the eggs were 14.4, 11.1, 8.5 days and the mean development time of the five nymphal instars from hatching to adult emergence were 24.6, 15.7, 13.1 days at 20, 25, 30 °C respectively. Adult female longevity was the longest at 20 °C (77.1±23.7 days) and the maximum egg was laid at 25 °C (94.9 egg). The sex ratios (♂/♀) were about the same (1:1.2, 1:1.2 and 1:1.3) at three temperature respectively. The highest net reproductive rate “R0†was 94.80 at 25 °C, the shortest mean generation time “T" was 31.08 days and the highest intrinsic rate of increase “r†was 0.134 at 30 °C. As high temperatures affected positively biology of Z. sohrab, population of the leafhopper may reach higher densities and create further damage, particularly on second crop maize.