Study on efficiency of Cryptolaemous montrouzieri Mulsant for control of Pulvinaria aurantii Cockerell

Orange pulvinaria scale, Pulvinaria aurantii Ckll., is one of the most important pest on citrus in north of Iran. At present, the farmers use chemical control methods to prevent crop losses by the pest. Using effective natural enemies has a special importance in controlling of this pest. The present investigation was conducted to determine the efficacy of coccinelid beetle, Cryptolaemus montrouzieri Muls. (Col.: Coccinellidae), and it's releasing time against orange pulvinaria scale in screen house and citrus orchard. The treatments were conducted in three different experiments with a completely randomized design. The result revealed that the feeding rate of adult coccinelid beetle (each pair) from ovisac of orange pulvinaria scale was 35 in a month. The result indicated that the best treatment in these experiments was twice ladybird beetle releases (one pair in the beginning of oviposition and another in the peak of egg sacs) in controlling the population of this pest.