Biology of Larinus affinis Fremuth on Echinops Aucheri Boiss in Kerman region

Document Type : Research paper-Persian

Abstract

The species of Larinus spp. feed on developing achiness of flowerhead of plants in the family Asteraceae and cause decrease in seed production of these plants. In this study, the life cycle parameters of the weevil Larinus affinis Fremuth on Echinops aucheri Boisswere studied in Kerman under natural conditions during 2010 and 2011. This weevil overwintered as adults under ground litter. The females inserted their eggs into the flowerhead of weed, usually one egg laid per flowerhead. The larvae feed on developing achiness of flowerhead and caused an average 95.6% decrease in seeds production in infested flowerheads. Overwintered females lived up 45.9±3.8 to 48.6±0.7 days. The mean of fecundity was 40.3±4.9 to 60.6±10.8 eggs per female. The eggs were hatched 6±0.3 to 8.3±0.3 days after being laid. Development of larvae and pupa required 51.4±0.4 to 53.6±0.5 days and 6.7±0.3 to 7.6±0.2 days, respectively. This weevil had one generation per year on the flowerhead of E. aucheri. The L. affinis larvae feed on developing achiness of flowerhead of E. aucheri and can be useful in prevention of reproduction of this weed in Kerman.