Relative bioefficacy of acaricide, Abamectin 1.9 EC against European red mite, Panonychus ulmi Koch. in apple

Various dosage viz., 0.3, 0.4, 0.5, 0.6 and 1.2 ml/l of newer acaricide, abamectin 1.9 EC against European red mite, Panonychus ulmi infesting apple crop at Harsil (2500 m ASL) in Uttarkashi district of Uttarakhand were compared with conventional acaricides viz., propargite 57 EC (0.5 ml/l), fenazaquin 10 EC (0.4 ml/l) and water spray. At highest dosage (1.2 ml/l), there was 73.7 and 77.0 per cent reduction of mite population on ₁st DAS which increased 90.0 and 97.3 per cent on 7^th das, during 1^st and 2^nd year, respectively. This was significantly superior with propargite 57 EC (0.5 ml/l) and fenazaquin 10 EC (0.4 ml/l). Significantly, highest yield (190.0 and 202 kg/tree) was recorded with highest dosage of abamectin 1.9EC (1.2 ml/l) followed by lower dosage (0.6 ml/l) of abamectin 1.9 EC (197.33 and 181.6 kg/tree) during two consecutive years.