Study on selective preferences of Harmonia axyridis(Pallas) collected from different habitats to predating aphids
yang yu-wu1; zhang qi-ming2; du lei3; qu ai-jun3(1.department of public affair adiminstration; adminanstration bureau of shengli petroleum field; shandong dongying; 257001; china; 2.dongying municipal project design institute; shandong dongying 257091; china; 3.college of science and technology; shandong agricultural university; taian; shangdong 271000; china)