Resumo

SAMANIEGO GAXIOLA, José Alfredo; AMAYA CARRILLO, José Emmanuel  e  PUENTE MANRIQUEZ, José Luis. Assessment of acetic acid like fumigant of silverleaf whitefly Bemisia tabaci (Gennadious) in laboratory and field. Rev. Mex. Cienc. Agríc [online]. 2012, vol.3, n.3, pp.413-426. ISSN 2007-0934.

The aim of this work was to assess the capacity of acetic acid (AA) like fumigant against Bemisia tabaci (silverleaf whitefly) which is a pest of national importance. In laboratory, the bug was fumigated with three doses-time regimes: (both media), low dose-long time and high dose-short time. In field, squash leaves of four varieties were fumigated with 8, 16 and 32 µg ml-¹ of AA during of 20, 40 and 60 min; additionally, it was assessed damage in foils (phytotoxicity) after fumigation. In laboratory, fumigation time > 15 min and 8µgml-¹ of AA killed 100% of whitefly, while its survival was reduced 40% when fumigated eight hours with 2 µml-¹ of AA; but control incubation (whitefly without fumigation) during ≥ 16 h also reduced its survival; meanwhile, with 8 and 16 µgml-¹ of AA the pest survival was reduced since five minutes (~20-80%). In field, the whitefly survived ~ 40% in leaves of four varieties afterfumigating with AA(8-32 µg ml¹)during20min, but pest practically did not survive when increasing fumigation time to 60 min. The leaves showed severe damage (phytotoxicity) > to 50% except in dose of 8µg ml-¹ at 20 min with damage of - 20%. Alternative to use of AA like fumigant are discussed.

Palavras-chave : biofumigants volatile fatty acids; vegetal protection..