1989年以前,椭圆萝卜螺Radix swinhoeiH.Adams,为害稻苗,仅个别田块零星发生,1992年扩散到9个大队,发生面积达7010亩,占水稻面积的53.9％,直播稻田发生面积大,受害重,一般每亩7300—14000头,高的达到25000—48000头;工厂小苗和地膜育秧的受害次之,一般每亩4000—8500头,大苗移栽几乎不发生。 Before 1989, the Radix swinhoeiH.Adams of Ellipopagrus did harm to rice seedlings and sporadic occurrences only occurred in individual fields. In 1992, it spread to 9 groups with an area of ​​7,010 mu, accounting for 53.9% of the total rice area. The area of ​​direct-broadcast rice fields was large, Heavy victims, generally 7300-14000 acres per acre, reaching 25000-48000 high; factory seedlings and plastic film seedlings suffer the second, usually 4000-8500 acres per acre, the transplanting of seedlings almost does not occur.