不同地区麦红吸浆虫圆茧过冷却点的测定

Detection on supercooling points of Sitodiplosis mosellana (Gehin) round cocoons in different geographical districts

为研究麦红吸浆虫的耐寒性,采集河南南阳、河南辉县、陕西西安、河北保定和天津等5个不同地区的麦红吸浆虫圆茧,分别测定其过冷却点。结果表明:麦红吸浆虫圆茧的过冷却点均随着纬度升高而显著下降,河南辉县种群圆茧过冷却点平均值最高,为-18.46℃;天津种群圆茧过冷却点最低,为-25.34℃;河南南阳种群和陕西西安种群圆茧过冷却点变异较大;不同地区的麦红吸浆虫的过冷却能力与各采样点1-2月极端低温呈显著正相关。

To investigate the cold adaptation of the orange wheat blossom midges, Sitodiplosis mosellana （Gehin）,their round cocoons were collected and sampled from 5 different geographical districts, including Nanyang and Huixian of Henan Province, Xi＇ an of Shaanxi Province, Baoding of Hebei Province,and Tianjin. Results showed that the supercooling points of the round cocoons significantly decreased with the rise of the latitude. The average supercooling point was maximum in Huixian colony, which was --18. 46℃, and minimum in Tianjin colony which was -25.34 ℃. There were large variations in Xi＇an and Nanyang colony, which have the lower latitudes and lower supercooling points. Supercooling points of round cocoons had positive relationship with local extreme low average temperatures in January and February.