Review of practical use of parasitoids for Tuta absoluta control in South América (Revisão do uso pratico de parasitoides para o controle de Tuta absoluta na America do Sul).

LUNA, M. G.; SALAS GERVASSIO, N.G.; SANCHEZ, NE

Ribeirao Preto

Simposio; 15 º Simposio de Controle Biologico; 2017

SEB - UNESP - ESALQ

Review of practical use of parasitoids for Tuta absoluta control in South América (Revisão do uso pratico de parasitoides para o controle de Tuta absoluta na America do Sul).María Gabriela LUNA, Nadia G. SALAS GERVASSIO, Norma E. SÁNCHEZ.CEPAVE (CONICET - UNLP). Boulevard 120 entre 60 y 64, (1900) La Plata, Argentina. lunam@cepave.edu.arThe vast majority of worldwide successful biological control of insect pests has been achieved by using parasitoid species. Studies on taxonomy and biology of Neotropical parasitoids have been predominant for over many decades, and a bulk of information has been gained on these insects. The South American tomato leafminer T. absoluta, a main tomato pest worldwide, proved to be attacked by a large number of parasitoid species, both in its region of origin and in the new invaded areas. In the Mediterranean basin, where the pest was accidentally introduced about 10 years ago, integrated pest management tactics were rapidly developed to control T. absoluta, which include the release and conservation of insect predators and parasitoids. However, in the horticultural sector in South America, chemical control remains at present as the most employed control tactic against this pest, what generates negative side effects such as pest genetic resistance and environmental contamination, including the disruption of natural enemy community development. This situation compels producers to overusing pesticides, spending up to 460 dollars per hectare each cropping season. Investigations aimed to the biological control of T. absoluta were initiated 25 years ago, in Argentina, Brazil, Chile and Colombia, and over 30 native or introduced parasitoid species were identified. They include species from six different parasitoid guilds: egg parasitoids (6 species), larval endoparasitoids (15 species), mid-larval ectoparasitoids (2 species), egg-larval parasitoids (3 species), larval-pupal parasitoid (1 species), and pupal parasitoids (5 species). To date, six of those parasitoid species have been selected for more detailed studies to determine their potential for the biological control of T. absoluta: the egg parasitoids Trichogramma nerudai and T. pretiosum, and Trichogrammatoidea bactrae; the larval endoparasitoids Apanteles gelechiidivoris and Pseudapanteles dignus, and the larval ectoparasitoid Dineulophus phthorimaeae. Mass rearing protocols, parasitism capacity, the functional response, and population parameters were estimated in the laboratory. Through field experimental work, the parasitism impact on pest populations under natural conditions, parasitoid releasing rates in semi-field trials in greenhouses, the side effects of insecticides commonly used in tomato fields on parasitoids, and the role of plant diversity adjacent to crops in promoting parasitoid´s presence have been assessed. Current reports state that only two parasitoid species are commercially developed as biocontrol agents of T. absoluta in South America: T. pretiosum and A. gelechidivoris. Besides, P. dignus and D. phthorimaeae have been proposed as candidates for conservation biological control. The adoption of commercial biological control in this region is discussed within the context of agricultural, commercial and socio-economic constraints. Since many countries in South America cope with similar phytosanitary problems and share plenty of natural enemies, collaboration with the research and agricultural communities would contribute to practical solutions that producers can implement in their crops.