福寿螺对水稻的为害及其产量损失研究

为了明确不同螺口密度和为害始期福寿螺为害与水稻产量损失的关系，于2007—2009年分别在早稻、单季晚稻和连作晚稻田通过人工定量投放福寿螺进行为害损失试验。结果表明：投放的时间越早，危害损失越大；投放的数量越多，危害损失越重。所有这些损失率与福寿螺密度之间的关系，均可采用幂函数方程来描述，以5%产量损失作为经济允许水平算的话，秧苗移栽后早稻田福寿螺密度宜控制在1只/m2以下，晚稻宜在3.5只/m2以下。福寿螺在早稻田的存活率在低密度下较高，而在晚稻田的存活率都不高，但是低密度下产卵量明显增多。建议要特别加强对水稻移栽后小苗期田间福寿螺的防控，最好能在移栽前对本田进行必要的防治，另外一旦断垄发生后要及时补苗，减少损失。

Injury and Yield Loss by the Golden Apple Snail Pomacea canaliculata Lamarck in Rice

To investigate the relationship among rice yield loss, the golden apple snail (GAS) (Pomacea canaliculata Lamarck) density and damage beginning time, the GAS was added to early rice field, late hybrid rice field and single late rice field artificially from 2007 to 2009. The results showed that, the earlier GAS was added to field, the more damage GAS caused. It was also identified that the more GAS added to the field, the more damage GAS caused. The power function equations could be used to describe the relationship between GAS density and yield loss. There should be less than 1 per m2 in early rice and field or 3.5 per m2 in late rice field if the yield loss was expected blow 5%. In early rice field, lower density was beneficial for higher survival rate. Although the survival rate was low in late rice field, the oviposition capacity would be higher with low density. It was important to control GAS after rice transplant. And preventing GAS before rice transplant would be better. To reduce yield loss, rice seedling should be added in time if seedlingless ridges happened.