FIELD SURVEYS ON THE NATURAL ENEMIES ASSOCIATED WITH SWALLOW-WORT (VINCETOXICUM SPP.) IN CHINA
2013 Annual Report
1a.Objectives (from AD-416):
Search for and identify potential biological control agents for swallow-worts (Vincetoxicum spp.). Determine basic biology in field and laboratory of promising insect agents and make preparations for preliminary host range studies.
1b.Approach (from AD-416):
Field surveys will be conducted in China during the growing season to identify the suite of natural enemies that utilize swallow-worts (Vincetoxicum spp.) as host plants. Insect specimens will be identified and colonies initiated for additional biological studies and future host range tests of insect species that appear promising for biological control.
Four field collection trips were conducted this past year in support of the swallow-wort biological control program – three in June, August and September 2012 in northeast China and one in April 2013 in southwest China. Six moth species, one butterfly species related to the monarch, two flea beetle species, one weevil species, two other beetle species, one type of larva boring the seed pods, one stink bug species, one very common plant bug species, and many aphids were collected from native Chinese swallow-wort plants. Some of the species could not be successfully reared and identified; others remain to be identified. Most of the insects damaged the leaves and are probably generalists, feeding on many kinds of plants. A preliminary host range test of one of the flea beetle species, considered the most promising natural enemy to date, was conducted. This flea beetle has been rejected from further consideration as a biological control agent because its host range is too broad.