Abstract
The distribution pattern of Aculops lycopersici (Massee) in a tomato leaf and method for estimating the density of the mite were examined. The distribution pattern of adults and nymphs was similar. About a half number of mite population infested leaflets and the other half petioles. Most of the mites infested the upper surface of the leaves. On petioles, the density of the mite was high at the posterior part. Mite numbers were large on leaflets near the stem. The percentage of the number of mite population on each part of the leaflet to the total number on whole leaf did not vary irrespective of the population density. On leaflets, the mite density was higher in the middle than periphery and also higher at the bottom than the top. However, the density became uniform in the leaflet when the density became high. From the distribution data obtained, a method for estimating the densities of mite population on whole leaf was proposed, i.e. mite numbers on the second and third leaflets and several parts of the petiole were counted.
