A natural predator indigenous to India, Neodumetia sangawani, was found useful in controlling the Rhodes grass-scale insect that was devouring forage grass in many parts of the US.
The results showed that pest increased as decrease of the neutral insectabundance, while predator abundance increased as increase of the insect abundance.
结果证明中性昆虫数量减少害虫数量增加，中性昆虫与害虫呈显著的负相关、与天敌呈显著的正相关。
3
The effect of predator, parasitoid, insect pest and neutral insect groups in the arthropod community in the weed habitat on the corresponding groups in the paddy habitat were varied.