Economic injury level of the psyllid, Agonoscena pistaciae, on Pistachio, Pistacia vera cv. Ohadi.
The pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer (Hemiptera: Psyllidae) is a major pest of pistachio trees, Pistacia vera L. (Sapindalis: Anacardiaceae) throughout pistachio-producing regions in Iran. Different density levels of A. pistaciae nymphs were maintained on pistachio trees by different insecticide dosages to evaluate the relationship between nymph density and yield loss (weight of 1000 nuts). Psylla nymph densities were monitored weekly by counting nymphs on pistachio terminal leaflets. There was a significant reduction in weight of 1000 nuts as seasonal averages of nymphs increased. Regression analysis was used to determine the relationship between nymph density and weight of 1000 nuts. The economic injury levels varied as a function of market values, management costs, insecticide efficiency and yield loss rate and ranged from 7.7 to 30.7 nymphal days per terminal leaflet, based on weight of 1000 nuts.
Reza Hassani
Mohammad
M
Department of Entomology, Science and Research Branch, Islamic Azad University, Tehran, Iran. mreza.hassani@yahoo.com
Nouri-Ganbalani
Gadir
G
Izadi
Hamzeh
H
Shojai
Mahmoud
M
Basirat
Mehdi
M
D000383:Agriculture / Q000191:economics; D000818:Animals; D006430:Hemiptera / Q000187:drug effects / Q000502:physiology*; D007300:Insect Control / Q000191:economics; D007306:Insecticides / Q000191:economics / Q000627:therapeutic use; D007492:Iran; D009758:Nymph / Q000187:drug effects / Q000502:physiology; D027927:Pistacia / Q000469:parasitology*; D010935:Plant Diseases / Q000191:economics* / Q000469:parasitology*; D013997:Time Factors
D007306:Insecticides