RELEASE OF CHRYSOPERLA CARNEA STEPHENS (NEUROPTERA: CHRYSOPIDAE) FOR CONTROL OF TETRANYCHUS URTICAE KOCH (ACARINA: TETRANYCHIDAE) ON PEACH GROWN IN A PROTECTED ENVIRONMENT STRUCTURE

Research into the feasibility of growing peach [ Prunus persica (L.) Batsch] in a protected environment structure (PES) was initiated in 1981 by the Ontario Ministry of Agriculture and Food at the Horticultural Research Institute, Vineland Station (Leuty and Miles 1983). The 0.2-ha PES comprised seven gutter-connected greenhouses, each 5.3 by 58.5 m, with 3.4-m gutter height fibreglass walls and a double polyethylene roof. Temperatures suitable for plant growth were obtained by capturing solar energy beneath the plastic enclosure. Diurnal temperatures ranged between 6 and 27°C. Relative humidity varied between 40 and 95% and remained above 90% within the covered structure for greater than 50% of the time period between bloom (March 20) and roof removal sometime in May.