Influence of Sunflower Genotypes on Parasitization Efficiency of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) on Helicoverpa armigera (Hiibner)(Lepidoptera: Noctuidae)

Two experiments were conducted on the effect of sunflower genotypes (21 nos.) on the parasitization efficiency of Trichogramma chilonis Ishii on Helicoverpa armigera (Hubner) under screen house conditions at Project Directorate of Biological Control (lCAR), Bangalore, Karnataka during 1999-2000. Pooled analysis of the data generated under these experinIents revealed significant difference in per cent parasitism of H. armigera eggs by T. chilonis on these genotypes. Highest parasitism was observed on sunflower hybrid MSFH 17 (53.50%) among all the genotypes evaluated. Second best performance was on variety Morden (42.50%), followed by RHA-274 (41.00%) and hybrid KBSH 1 (38.00%). However, statistically all these were on par. Least parasitism was recorded on hybrid BSH-I (8.00%), followed by variety 6D·l (9.50%) and accession no. 109 (12.50%). Strangely, both parent lines of this hybrid, namely, CMS 234A and RHA 274, recorded much higher parasitism. All other genotypes recorded low to moderate parasitism ranging from 16.00 to 34.50 per cent. The sunflower genotypes (hybrids, cultivars, inbred lines), which are found T. chilonis friendly, are also agronomically acceptable. Among them, two are important national high yielding (seed and oil) hybrids (MSFH 17 and KBSH 1).