Bio-ecology of Cassida rubiginosa fed on Silybum marianum and Onopordum boissieri in laboratory conditions

Cassida rubiginosa Muller (Coleoptera: Chrysomelidae) is a polyphagous pest and commonly distributed across the world. This species regarded as natural enemy of weeds by many researchers, while it also some cultivated plants. In this study, biological parameters C. fed on S. marianum O. boissieri (Asteraceae) were investigated.Average periods egg 5 larval stages, pre-pupa, pupa total development 6.67, 7.71; 2.04, 2.19; 2.05, 2.45; 2.01, 2.74; 2.58, 3.26; 4.41, 4.88; 1.63, 2.12; 5.64, 5.35 26.99, 30.35 days, respectively. There significant differences between all except stage scolymus. Biological calculated Intrinsic rate increase: 0.018, 0.017; Net reproductive rate: 214.16, 357.71 Mean generation time: 297.41, 337.19 for populations which used host,