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研究结果表明，水稻种植密度和生育期对三化螟Ｓｃｉｒｐｏｐｈａｇｅｉｎｃｅｒｔｕｌａｓ卵的天敌种群及其捕食率和寄生率有显著的影响。捕食性天敌和某些寄生蜂的种群密度随种植密度的增加和生育期的增长而增加，但啮小峰和赤眼蜂对种植密度的反应不明显。螟卵捕食率随种植密度的增加和生育期的增长而增加。但螟卵寄生率则相反：种植密度低、生育期早，卵寄生率高，且差异显著。种植密度和生育期不仅影响了单种寄生蜂的寄生率，而且也影响了螟卵寄生蜂种类的多少。在种植密度低的地块和水稻生长初期，卵块通常有３种寄生蜂出现，而在密度高的地块和生长末期，卵块通常没有寄生蜂或仅有赤眼蜂出现。虽然卵捕食和卵寄生都是三化螟卵的重要控制因素，但由天敌所造成的卵死亡率则随种植密度的增加或生育期的延长而下降。
The results showed that the density and growth period of rice had significant effects on the predators population, predation rate and parasitism of Scirpophageincertulas eggs. The population densities of predatory natural enemies and some parasitic wasps increased with planting densities and growth periods, but the responses of Gou Xiaofeng and Trichogramma to planting density were not obvious. The prey on the borer eggs increased with planting density and growth period. However, the parasitism rate of cucumber eggs is the opposite: the planting density is low, the growth period is earlier, the egg parasitism rate is high, and the difference is significant. Planting density and growth period not only affect the parasitism of a single parasitoids, but also affect the number of parasitoids beetle eggs. At low planting plots and early rice growth stages, there are usually three parasitoids present in the egg mass, whereas in the most densely populated and late-growing stages the egg mass is usually free of parasitic wasps or only of Trichogramma. Although egg prey and egg parasitism are both important control factors for the eggs of the rice stem borer, the egg mortality caused by natural enemies decreases with increasing planting density or growth period.