Exploratory survey in Venezuela for biological control agents of Passiflora mollissima in Hawaii

Passiflora mollissima (H.B.K.) Bailey, a South American vine that grows at high altitudes, is the most important weed pest of the upper-elevation rain forests of Hawaii. Mechanical and chemical methods of controlling this weed are impractical and expensive. Natural enemies appear to restrain this mem ber of the Passifloraceae in its native Andean countries, and the introduct ion of biological control agents to Hawaii is the only viable control metho d available. Previous surveys of natural enemies of P. mollissima in its na tive range resulted in the introduction but unsuccessful establishment of t wo agents, calling for a renewed search for candidate insects. Detailed stu dies were conducted for 4 years in Venezuela to survey and evaluate insects attacking P. mollissima Twelve insect species may have an important effect on the growth and reproduction of this target plant. Three bud-feeding spe cies, Zapriothrica salebrosa Wheeler (Diptera: Drosophilidae), a Mycetophil a sp. (Diptera: Mycetophilidae), and Pyrausta perelegans Hampson (Lepidopte ra: Pyralidae), as well as a fruit feeder, Dasiops caustonae Norrbom and Mc Alpine (Diptera: Lonchaeidae), limited flower and fruit production and were believed to play the most important role in regulating wild stands of P. m ollissima in Venezuela. The mycetophilid and D. caustonae were not collecte d from previous surveys and are recommended as potential biological control agents, (C) 2000 Academic Press.