Phytotoxicity to kiwifruit of oil sprayed after flowering

Evaluation of a mineral oil for pest control on kiwifruit

“…P<0.01 and P<0.001 for reddening and specking respectively. The higher level of fruit speckling recorded on the vines treated with 1 and 2% oil than that recorded with the same treatments by (McKenna and Steven 1993) is probably due to the accidental inclusion of the sticker.…”

“…These include the use of higher than normal water rates and the timing of oil applications. In particular, oils do not have a label claim for use from 10 days after flowering until February 1 due to the risk of phytotoxicity as indicated in this trial, and confirmed by more detailed investigations (McKenna and Steven 1993). Treatments were replicated six times in a completely randomised block design using single vine plots buffered by unsprayed vines.…”

“…Significant differences were found between treatments in the levels of both darkened leaf edges and spotting damage (P<0.001 and P<0.05 respectively), with the incidence of both types of leaf damage higher on oil than phosmet-treated vines (Table 4). This damage was probably caused by the oil application made in early January which coincides with the period when kiwifruit are sensitive to chemical applications (McKenna and Steven 1993). Speckling of the skin of fruit harvested on 15 January 1989 was only found for vines treated with 2% oil (8% of fruit).…”

“…Their introduction was hampered by phytotoxicity problems in early attempts to control armoured scale insects on kiwifruit (Sale 1972). These problems were overcome by the development of more highly refined oils and the identification of factors influencing phytotoxicity on kiwifruit (McKenna and Steven 1993).…”

Control of insect pests in persimmon with spray oils

“…The primary concern in the use of oils on fruit crops is their potential for phytotoxicity. While pest control is likely to be improved by applying higher rates of oil, this increases the risk of damage to fruit (McKenna and Steven 1993).…”