Apple, Petal-Fall vs Pink Test, 1985

Abstract

Abstract A 15-year-old orchard located at the Rutgers Fruit Research & Development Center, Cream Ridge, NJ was used in this test. Sprays were applied to 3 single-tree replicates of ‘Red Delicious’ arranged in a randomized complete block design. Trees were sprayed to runoff (ca 5 gal/tree; 300 GPA) using a hydraulic sprayer equipped with a hand-gun and operated at 200 psi. Spray dates were 11 Apr (P) and 30 Apr (PF). For disease control the entire orchard was sprayed with Captan and Polyram as needed. European red mite estimates were made by randomly picking 25 leaves per replicate, brushing the mites onto glass plates and counting mobile mites. Sampling methods for insects listed in the table are as follows: EASF = no. of EASF damaged fruit/3 minute count; AA = avg no. of AA/terminal/tree (20 terminals counted); RAA = no. of RAA colonies/tree; STLM = no. of STLM mines/3 minute count; WALHa = no. of WALH nymphs and adults/3 minute count; WALHb = no. of WALH damaged leaves/3 minute count; Stethorus = no. of S. punctum larvae, pupae and adults/3 minute count; Russet = % russet/fruit (100 fruit evaluated). Mite-days were calculated as follows: MD = MD1 + [(Ml + M2)/2 × Y], where MD1 = mite days already accumulated, Ml = avg ERM/leaf on a given counting date, M2 = avg ERM/leaf on the next counting date after Ml and Y = number of days between Ml and M2. Data were transformed to × + 1, or arcsin (x) prior to analysis of variance and comparison of means. In tables, numbers followed by the same letter are not significantly different (alpha = 0.05, DMRT).