BUSCADOR RECOLECTA

Acceso cerrado a este documento. No se encuentra disponible para la consulta pública. Depositado en Academica-e para cumplir con los requisitos de evaluación y acreditación académica del autor/a (sexenios, acreditaciones, etc.)., Chrysodeixis chalcites is an emergent pest in bananas (Musa acuminata Colla) grown on the Canary Islands. Feeding damage to leaves and fruit and the control measures targeted at this pest were evaluated over a two-year period (2013–2014). The prevalence of infestations (42–100%) on the islands was similar during the two years of the study. Mean foliar damage (1.5–7.3% depending on island) and fruit damage (1.0–5.7%) detected in field surveys varied significantly across islands, plantation aspect (north- or south-facing) and season. Fruit damage was not correlated with foliar damage (P > 0.05). The weight of C. chalcites damaged bananas varied significantly (0.2–4.2% of harvested fruit) across islands, particularly in the spring. Overall, 3155 tonnes of bananas/yr are likely discarded due to C. chalcites damage, representing 1.5% of annual production or 2.68 million €/yr. The most frequently used pesticide was indoxacarb, usually applied on three occasions per crop cycle, for which the cost of control measures would average 240 €/ha per crop cycle. The direct damage that C. chalcites causes to banana fruit results in significant economic losses in addition to the direct costs of pesticide based control measures. Effective and sustainable control strategies are required against this pest., The study received financial support from the National Institute for Agricultural and Food Research and Technology (INIA) from the Spanish Ministry of Economy, Industry and Competitiveness project numbers RTA2010-00016-C02 and RTA2013-00114-C02.

Acceso cerrado a este documento. No se encuentra disponible para la consulta pública. Depositado en Academica-e para cumplir con los requisitos de evaluación y acreditación académica del autor/a (sexenios, acreditaciones, etc.)., Background: a Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system.
Results: the sixth instar (L6) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4) or fifth (L5) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165–175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011) or per mg larval weight (1.30 × 1011 to 2.11 × 109), in larvae inoculated with a range of inoculum concentrations (LC50–LC90). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container).
Conclusion: the processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container., his study received financial support from the Instituto Nacional de Investigaciones Agrarias (Project RTA2010-00016-C02-02 and RTA2013-00114-C02-02) and the Programa Nacional Español de I + D + I (Projects AGL2008-05456-CO3-01 and AGL2011-30352-CO2-01).