There were obviously more chafers near the castor-oil plant than soybean, cotton, sweet potato, peanut, elm, Abutilon theophrasti Medic, there was significant difference between them.

• 华北大黑鳃金龟对田间笼罩植物的选择反应 从田间观察中发现，在蓖麻植株附近的金龟甲数量明显高于大豆、棉花、红薯、花生、榆树、苘麻，其间差异显著。