The sex ratio, circadian emergence rhythm and activity patterns of adult oriental fruit moth, Grapholitha molesta (Busck) (Lepidoptera: Tortricidae)

Author of the article:RAN HongFan**LU ZiYun***LIU WenXuQU ZhenQangLI JianCheng

Author's Workplace：Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences;

Key Words：oriental fruit moth, sex ratio, emergence rhythm, activity pattern, peach orchard

Abstract：Oriental fruit moth is an important pest of fruit trees in China. The sex ratio and circadian emergence rhythm of adult oriental fruit moth, Grapholitha molesta (Busck) was investigated by rearing in laboratory, simulant field conditions and collecting in orchards for rearing. And the activity patterns of oriental fruit moth was investigated using sex pheromone, sweet and sour liquid and blacklight lamp for trapping. The results showed that: 1. the ratio of female and male moths was 1∶1.143 in field populations, and 1∶1.708 in laboratory populations. 2. the emergence time of adult oriental fruit moth was mainly in 4：00—10：00, among which the highest emergence rate was in 6：00—8：00; in field, the emergence time was later for 2 h than in laboratory, and as for days, 4 d later than in laboratory, this would because of the temperature and illumination in field; the female moths emerged earlier than male for 1-2 days; 3. the trapping peak in sex pheromone and sweet and sour liquid were also in 20：00—22：00, which indicated that all the male and female activity in this time; the blacklight lamp could trap moth in all the time, which indicated that the oriental fruit moth has phototaxistic. The conclusions: the sex ratio of oriental fruit moth was 1∶1.1—1.7 (female∶male); and the oriental fruit moth was mainly emergence in morning, and female emergence earlier than male; it was active in early evening 20：00—22：00. This can provide direction for oriental fruit moth attraction, monitoring and mating disruption.