A Note on the Effect of the Fertilizers on the Population Dencity of the Tea Red Spider Mite, Tetranychus Kanzawai KISHIDA, on the Tea Plant

Abstract

The tea red spider mite, Tetranychus kanzawai KISHIDA, is the most common pest of the tea plant in Japan. This paper deals with the effect of the fertilizers on the population dencity of the mite. The results were as follows :1. On the sand culture and pot experiment tests, it was found that the kinds and quantities of the fertilizers influenced on the mite population.2. The mite population on the tea plants of high nitrogen and phosphorus manuring was much more than that of the low level plots.3. On the contrary, the mite population on the low levels of potassium and manganese manuring was much more than on the high level ones.