Overwintering of pear leaf blister mite, Eriophyes sp.2, and subsequent fruit damage in pear orchards in Yamagata Prefecture, Japan.
Studies were conducted to investigate the overwintering site of the pear mite (Eriophyes sp.) occurring in pear in the Shonai area of Yamagata Prefecture, Japan, the time of withdrawal from the overwintering site, the time of migration to the overwintering site, and the damage to the fruits during the growing season. It was shown that overwintering of the pear mite occurred inside the bud scales. The parasitic bud rate of the apical flower bud was high and the number of parasitized insects was large. Withdrawal started around the germination stage, but it was found that the inside of the bud, which was the overwintering site, was damaged without early withdrawal, causing blistering symptoms. In addition, although it was not possible to clarify the time of migration into the bud scales in the latter half of the growing season, it was shown that the migration continued until the end of November. It was speculated that the rust symptoms appearing on the fruits were caused by the invasion of this species into the tentacles and could not be harmed after the juvenile stage.