The role of phenolic compounds on abundance of olive psyllid, Euphyllura straminea Loginova on commercial and promising olive cultivars

Abstract

Olive psyllid, Euphyllura straminea Loginova has been reported as a key pest of olive in Iran. Field observations have shown that infestation rate of various olive cultivars to olive psyllid are different. This study aimed to determine the levels of total phenol and 3, 4-dihydroxyphenylethanol (DHPE), as well as the horticultural traits of various olive cultivars Zard, Conservolia, Arbequina, Picual, Cornicabra, Kaissy, Direh, and Koroneiki and how they correlate with the infestation rates of the olive psyllid. The maximum and minimum number of psyllid nymphs were observed in Arbequina (19.79 ± 2.28) and Direh (2.13 ± 0.38) cultivars respectively. In contrast the highest and lowest amount of DHPE were recorded in inflorescences of Direh (11.47 ± 0.54 mg/g) and Arbequina (5.37 ± 0.30 mg/g) cultivars, respectively. Furthermore, negative correlation between the amount of total phenol and the number of nymphs on the inflorescence of olive cultivars. It was concluded that DHPE phenolic compound might play and effective role in pest attack.