Control of insect pests in persimmon with spray oils

Abstract

The efficacy and safety to plants of mineral spray oils for use against mealybugs were assessed in field trials on persimmon. Repeated applications of oil and adjuvant-enhanced oil in the three months prior to harvest had no deleterious effects on fruit size or quality. Fortnightly applications of such oils in a commercial orchard maintained fruit insectfree. Oil sprays, enhanced with alkylsilicone adjuvant, provided significant control of mealybugs, and mites, in a persimmon orchard subjected to intensive pest pressure close to harvest. Addition of oil to insecticide used at half the recommended rate gave equivalent insect control to the full-rate insecticide regime. Oil had no effect on insecticide residues, which were halved in the half-rate treatment.

Efecto del coadyuvante siliconado e insecticidas en el control del chanchito blanco de la vid, Pseudococcus viburni (Hemiptera: Pseudococcidae)

“…Al aplicar 1.500 L•ha -1 en el campo, el uso de coadyuvante junto con la mitad de la dosis utilizada para controlar a P. longispinus en caqui, Diospyros kaki. Gaskin et al (1996) controlaron igual que con la dosis máxima del insecticida sin coadyuvante, y mejor que con la mitad del insecticida aplicado solo. Para uva vinífera, los volúmenes de aplicación pueden reducirse si se usan los adyuvantes apropiados, sin comprometer la efi cacia del insecticida (Gaskin et al, 2002).…”

Tyeid mite control on persimmons

“…Previously, Prestidge et al (1989) had found that fruit contamination could be reduced by a single spray of some insecticides five days before harvest. However, neither single (Prestidge et al 1989) or multiple (Table 2, Gaskin et al 1996) pre-harvest applications of any of the pesticides tested were able to provide fruit free of tydeid mites.…”

“…No significant differences between treatments in the level of fruit contamination at harvest were found, although mineral oil used alone or with the surfactant Silwet 560 did considerably reduce fruit contamination. Similarly, Gaskin et al (1996) had found that fruit contamination could be reduced with three applications between mid-April and mid-May of mineral oil (Shellspray All Purpose oil) used alone or with a surfactant (Y-12780). Previously, Prestidge et al (1989) had found that fruit contamination could be reduced by a single spray of some insecticides five days before harvest.…”

Modelling of pesticide residues on fruit II: persimmon

“…Model predictions for particular pesticides, spray timings and preharvest intervals were compared to laboratory residue data for: an adjuvant plus insecticide trial in the Waikato (Gaskin et al 1996); two grower trials in the Waikato and Bay of Plenty using standard spray programmes (air blast application) and a persimmon industry quality assurance programme for the 1995 harvest covering 68 orchards. Fruit samples taken within 21 days of main harvest were tested for pesticide residues by multi-residue procedures (National Chemical Residue Laboratory, MAF Qual, Wallaceville) and grower spray diaries were also made available.…”