Pest status of leaf miner, Acrocercops syngramma M. on common varieties of cashew in Puttur region of Karnataka

Abstract

Studies were conducted in a cashew plantation at Puttur, Karnataka, India during 2011 - 14 using 11 common cashew varieties during post monsoon flushing period to determine the pest status of leaf miner, Acrocercops syngramma M.Maximum number of larvae in a single leaf ranged between 15 and 45 among the varieties. Least larval density was recorded on NRCC-Sel-2 followed by Vengurla-4, while, highest was recorded on Ullal-4, V-7 and MDK-2. In most of the varieties,there was no significant relationship between the leaf area and the number of leaf miner larvae. Considering the average leaf area of infested leaves and the average leaf area damage, the number of larvae required for a complete leaf was calculated between 17.4 and 29.1. Which was highest for Bhaskara and lowest for V-1. Distribution of number of leaf miner larvae against the percentage of infested leaves revealed that, nearly 90 percent of infested leaves had number of larvae between 1 and 10. During the four years, the leaf miner pest status remained as low to medium in all cashew varieties.