Studies on the Supercooling Point of Ericerus pela at Different Instars and Overwintering Female Adults of Different Geographic Populations Cold hardiness of beet armyworm, Spodoptera exigua ON THE OVERWINTERING AND COLD-HARDINESS OF THE VEGETABLE LEAFMINER LIRIOMYZA SATIVAE BLANCHARD A study on the cold hardiness of the beet armyworm,Spodoptera exigua