PROTEASE INHIBITORS OF MANDUCA-SEXTA EXPRESSED IN TRANSGENIC COTTON

To explore the effectiveness of insect derived protease inhibitors in protecting plants against insect feeding, anti-trypsin, anti-chymotryp sin and anti-elastase protease inhibitor (PI) genes from Manduca sexta L. were expressed in transgenic cotton (Gossypium hirsutum L.). From 198 independent transformants, 35 elite lines were further analyzed. U nder the control of the 35S promoter of CaMV, PI accumulated to approx imately 0.1% of total protein, depending on the tissue analyzed. Using cell-flow cytometry, DNA content/nuclei of transgenic and nontransfor med cotton were identical. On cotton plants expressing PIs, fecundity of Bemisia tabaci (Genn.), the sweetpotato whitefly, was reduced compa red to controls. Expression of these protease inhibitors may reduce th e developmental rate of B. tabaci and other insects, and provide a str ategy for cotton protection.