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云南水叶甲(Donacia tuberfrons Goecke)是凉山地区水稻的主要地下害虫。在海拔1700—2200m,冬春干旱达半年以上的高寒稻区发生更为普遍。越冬后的幼虫为害水稻根部,一般减产3—4成,严重的可达7—8成,对水稻生产威胁很大。云南水叶甲在凉山地区一年发生一代,幼虫在冬炕田10—30cm 土层内越冬,严重为害期在5月下旬至6月中旬水稻移栽后。发生区内的植被组成、产卵及土壤质地是影响幼虫数量变动的主导因素。雌雄性比为1:0.9。各虫态历期平均为:成虫6.6—9.5天,卵15.3—19.5天,幼虫291—323.8天,蛹7.7—8.1天。彻底清除田间杂草(特别是眼子菜 Potamogeton distinctus A Benn.),减少产卵场所,是控制该虫发生的有效途径;用毒土(50%甲胺磷乳油1:150倍土)于水稻移栽前撒施耙匀,对控制和消灭幼虫为害有显著效果。
Donacia tuberfrons Goecke is the main underground pest of rice in Liangshan area. At an altitude of 1700-2200m, winter and spring drought occurred more than six months in the alpine region occurs more prevalent. After larvae larvae damage rice roots, the general reduction of 3-4 percent, a serious up to 7-8 percent, a great threat to rice production. Yunnan A leafworm occurs in Liangshan area a year, the larvae in the winter kangtian 10-30cm soil overwinter, a serious damage period in late May to mid-June after transplanting rice. The occurrence of vegetation, spawning and soil texture in the area are the main factors affecting the number of larvae. Male to female ratio was 1: 0.9. The average duration of each state was as follows: Adults 6.6-9.5 days, eggs 15.3-19.5 days, larvae 291-323.8 days, pupa 7.7-8.1 days. Thoroughly eliminate the weeds in the field (especially Potamogeton distinctus A Benn.), Reduce the spawning sites, is an effective way to control the occurrence of the worm; with toxic soil (50% methamidophos EC 1: 150 times) in rice Spread before raking spread evenly on the control and elimination of larvae have a significant effect.