HOST-RANGE OF THE ARGENTINE ROOT BORER CARMENTA-HAEMATICA (URETA) (LEPIDOPTERA, SESIIDAE), A POTENTIAL BIOCONTROL AGENT FOR SNAKEWEEDS (GUTIERREZIA SPP) IN THE UNITED-STATES
Ha. Cordo et al., HOST-RANGE OF THE ARGENTINE ROOT BORER CARMENTA-HAEMATICA (URETA) (LEPIDOPTERA, SESIIDAE), A POTENTIAL BIOCONTROL AGENT FOR SNAKEWEEDS (GUTIERREZIA SPP) IN THE UNITED-STATES, Biological control, 5(1), 1995, pp. 1-10
The Argentine root-boring sesiid moth Carmenta haematica (Ureta) is re
stricted in Argentina to plants of two genera, Grindelia and Gutierrez
ia (Asteraceae: Astereae). Field examination of 51,622 plants of 67 sp
ecies of Asteraceae at 286 locations revealed that larvae completed th
eir development only in Grindelia chiloensis (Corn.) Cabrera, Grindeli
a tehuelches Cabrera, Gutierrezia solbrigii Cabrera, Gutierrezia spath
ulata (Phil.) Kurtz., and Gutierrezia mandonii (Sch. Bip.) Solbrig. In
multiple-choice tests in the laboratory, using cut stems of 37 specie
s in 27 genera and eight tribes of Asteraceae, 93.5% of the neonate la
rvae that entered stems entered those of 4 species of Grindelia and Gu
tierrezia and 95.7% entered these plus the 1 other species of the subt
ribe Solidagininae tested. In no-choice tests using potted plants in t
he laboratory garden, neonate larvae placed in holes drilled in the st
ems of 28 species of plants developed to the adult stage only in Gr. c
hiloensis but reached the fourth instar also in Grindelia pulchella Du
n., Gu. solbrigii, and Solidago chilensis Meyen. The no-choice and mul
tiple-choice laboratory tests, interpreted through the three basic ele
ments of host specificity of insects, support the host range observed
in the field. C. haematica is the most specific insect yet tested for
biological control of snakeweed. It is sufficiently host specific for
introduction into quarantine in the United States for further testing
and possible future release in the field.