Studies On The Opvisition Preference Of Helicoverpa Assulta Guenée And H.armigera H(?)bner To Two Varieties Of Tobacco And Preliminary Selection Of Attractant

This thesis took makhorka, K326, H. assulta. and H. armigera as research objects, through a series of experiments caged in field and laboratory, determined different oviposition preference of H.assulta and H. armigera to two crops of tobacco. According to the results of analysis of tobacco crude bioextracts and biomeasurement in labaratory, the single reagent and the compound were selected, and the attraction effection of the compounds was researched in field. The main results are as follows:Oviposition preference of H. assulta and H. armigera to two crops of tobacco. Oviposition preference of H. assulta and H. armigera. to two crops of tobacco was studied by tests caged in field and in laboratory. The results showed that the relative oviposition rate of H. assulta on makhorka is 5.77 times more than on K326, and the difference is significant. On the contrary, the relative oviposition rate of H. armigera on K326 is 7.29 times more than on makhorka,and the difference is significant. The result of test caged in laboratory and in field is similar, tobacco budworm prefer makhorka crude bioextracts in ovipositing, and eggs on the floral organ crude bioextracts is more than that on the leaves. Cotton boolworm prefer K326 crude bioextracts in ovipositing, and eggs on the floral organ crude bioextracts is also more than that on the leaves.The composing of crude bioextracts of makhorka and K326 53 compounds were separated from the floral organ distillation extraction of k326 (RT< 26.50 m), the main component is nicotine and its relative content is 47.92%. Secondly component is solanone and its relative content is 18.70%. As to the results, the crude bioextracts include 8 kinds of alcohols(such as lef alcohol, n-hexyl alcohol), 10 kinds of aldehydes (such as benzaldehyde, phenylacetaldehyde), 12 kinds of ketones (such as 3,5-dimethyl cyclohexanone, solanone) and esters (such as benzyl acetate, ethyl benzoate). 32 compounds were separated from the solvent absorption of the K326 floral organ volatiles (RT< 28.80 m), the main components are nicotine and solanone, their relative contents are 16.83% and 12.31% respectively. Secondly components are ethyl benzoate and benzyl alcohol, and their relative contents are 6.35 % and 3.17...