Geographic Variation of Diapause Induction Rates in Trichogramma drendrolimi (Hymenoptera: Trichogrammatidae) in China.
Diapause variation is a key factor affecting the development and success of parasitoids employed as biological control agents. Trichogramma dendrolimi Matsumura is mass-reared for biocontrol purposes in several countries around the world. Here we investigated the rate of diapause induction in three populations of T. dendrolimi from different regions in China: Heilongjiang (44° 55' N, 128° 26' E; HLJ), Liaoning (40° 18' N, 123° 22' E; LN), and Jiangsu province (32° 30' N, 120° 09' E; JS). We measured the rates of diapause induction for populations from each region when exposed to temperatures of 8, 10, 12, and 14 °C, for periods ranging from 5 to 35 d. Results showed that both the temperature and exposure duration influenced diapause induction in the three populations of T. dendrolimi. The HLJ and LN populations showed the highest percentage of diapause under 12 and 10 °C, regardless of time period tested. After 20 d at 12 and 10 °C, 97.42% and 95.94% of individuals of HLJ and LN, respectively, entered diapause. After treatment for 20-35 d under 8 °C, or 15-25 d under 10 °C, the diapause rate of LN was higher than those of the other two populations. In contrast, the higher temperatures (12-14 °C) induced diapause rapidly and steadily in HLJ. The diapause rate of JS was low for all temperatures and time periods. After 30 d at 12 °C, the JS population reached its highest diapause rate (29.56%). Our results showed significant variance in diapause rates among geographically distinct populations of T. dendrolimi in response to various abiotic conditions.
Engineering Research Center of Natural Enemy Insects, Institute of Biological Control, Jilin Agricultural University, Changchun, China (junjiezh@126.com; lsz0415@163.com; 280114191@qq.com; bio-control@126.com).
Jun-Jie
JJ
Zhang
INRA (French National Institute for Agricultural Research), Univ. Nice Sophia Antipolis, CNRS, UMR 1355-7254, Institute Sophia Agrobiotech, 06903 Sophia-Antipolis, France (nicolas.desneux@sophia.inra.fr).
Nicolas
N
Desneux
Insect Behavior Group, Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy (benelli.giovanni@gmail.com).
Giovanni
G
Benelli
Engineering Research Center of Natural Enemy Insects, Institute of Biological Control, Jilin Agricultural University, Changchun, China (junjiezh@126.com; lsz0415@163.com; 280114191@qq.com; bio-control@126.com).
Lian-Sheng
LS
Zang
Engineering Research Center of Natural Enemy Insects, Institute of Biological Control, Jilin Agricultural University, Changchun, China (junjiezh@126.com; lsz0415@163.com; 280114191@qq.com; bio-control@126.com).
Wen-Mei
WM
Du
Engineering Research Center of Natural Enemy Insects, Institute of Biological Control, Jilin Agricultural University, Changchun, China (junjiezh@126.com; lsz0415@163.com; 280114191@qq.com; bio-control@126.com).
Chang-Chun
CC
Ruan
D000818:Animals; D002681:China; D064666:Diapause, Insect; D005843:Geography; D007814:Larva / Q000254:growth & development / Q000469:parasitology / Q000502:physiology; D009036:Moths / Q000254:growth & development / Q000469:parasitology; D013696:Temperature; D014863:Wasps / Q000254:growth & development* / Q000502:physiology
abiotic factor; biological control; inducing period; parasitoid; temperature