| Abstract | dc.description.abstract | The effect of pyriproxyfen, phenoxycarb, chlorpyrifos,
and mineral oil in the control of first generation nymphs
of the San Jose scale (SJC), Diaspidiotus perniciosus
(Comstock), in almond, Prunus dulcis (Mill.) D.A. Webb,
and apple, Malus domestica Borkh. orchards was studied
in the 2001-2002 season in central Chile. One and two
sprays of pyriproxyfen 0.07% and phenoxycarb 0.05%
were applied, the first at the beginning of the appearance
of nymphs in early spring (biofix), and the other 15 days
later, and were compared with one spray of chlorpyrifos
0.08% applied at the biofix. Also, one and two sprays of
mineral oil 1% were evaluated, the first applied 7 days
after the biofix, and the second 15 days after the first spray.
Evaluations were done in the laboratory at the end of the
dispersion of first generation nymphs, on December 27
and 28 for almonds and apples, respectively, counting the
number of nymphs fixed per lineal meter of new twigs
collected at infested sectors, percentage of infested apples,
and the number of scales fixed per fruit. Results were
subjected to ANOVA and Duncan multiple range tests.
At low level infestation, one application of pyriproxyfen
0.07%, phenoxycarb 0.05%, or mineral oil 1% in spring
reduced significantly (P ≤ 0.05) the number of nymphs
fixed per twig, at a level similar to that of a traditional
treatment of chlorpyrifos 0.08%. However, at greater
infestations, one spray of pyriproxyfen or mineral oil in
spring was insufficient to control ESJ. | en_US |
