THE EFFECT OF TEMPERATURE ON REPRODUCTION BY THE ALATAE OF PEMPHIGUS BURSARIUS (L.)

The reproductive rate of the winged forms of Pemphigus bursarius was studied at temperatures between 38 and 82° F. The fundatrigeniae gave the greatest total reproduction at about 60° F. but the highest reproductive rate at 70–81° F. Corresponding temperatures for the sexuparae were 55 and 67° F. approximately. The average outdoor air temperatures prevailing at the time when the respective winged forms are most abundant correspond closely to the temperatures required by the alatae for maximum reproduction. On a basis of temperature, adult sexuparae trapped underground can expect to survive about 12 days in early September and about 30 days at the end of October.