PHENOLOGY OF HOPLOCAMPA MONTANICOLA ROHWER (TENTHREDINIDAE) AND ANTHONOMUS QUADRIGIBBUS SAY (CURCULIONIDAE) ON THEIR HOST PLANT AMELANCHIER ALNIFOLIA NUTT. (ROSACEAE) IN SASKATCHEWAN

Abstract

AbstractAdult Hoplocampa montanicola Rohwer emerged in mid-May, 6.2 ± 3.2 days (mean ± SE) prior to the period of peak anthesis in Amelanchier alnifolia Nuttall. Oviposition, one egg per flower, occurred during the period of petal drop in late-May; a mean ± SE of 2.2 ± 0.2 eggs were deposited in each inflorescence. Eggs hatched 7.7 ± 3 days (mean ± SE) after the period of primary petal drop and larvae fed on a mean ± SE of 1.8 ± 0.14 fruit per infructescence. Larvae completed development by the end of June, just as the first fruit of A. alnifolia were beginning to ripen. Larvae overwintered in the leaf litter.Adult Anthonomus quadrigibbus Say (previously assigned to the genus Tachypterellus) were first collected in mid- to late-May during the periods of anthesis and fruit drop in A. alnifolia. Immature fruit fed upon were often extensively damaged. Oviposition occurred toward the end of fruit drop in A. alnifolia, 30.6 ± 2.5 days (mean ± SE) after the period of peak anthesis. Only one egg was laid in a puncture at the base of a fruit. Larval feeding was restricted to ovules and occurred in fruit retained on the plant. Pupation and adult emergence occurred in mid-July as fruit were ripening. The new generation of adults then entered the leaf litter to overwinter.