《棉花姑娘》资料袋

1．蚜虫

蚜虫(chong)是(shi)一(yi)种昆虫(chong)，身体卵(luan)圆(yuan)形，绿色(se)、黄色(se)或棕色(se)，腹部大。吸食植物的汁液(ye)，是(shi)农(nong)业害(hai)虫(chong)。种类很多，如棉蚜、烟(yan)蚜。通(tong)称腻虫(chong)。有(you)的地区叫蜜(mi)虫(chong)。

2．七星瓢虫

瓢(piao)虫(chong)(chong)的(de)一种(zhong)，因背部(bu)像葫芦(lu)瓢(piao)而(er)得名。根据(ju)食(shi)性(xing)，瓢(piao)虫(chong)(chong)可分(fen)为(wei)植(zhi)食(shi)性(xing)与肉食(shi)性(xing)两(liang)大类群。前(qian)者以(yi)植(zhi)物(wu)为(wei)食(shi)，对人类有(you)害(hai)(hai)，但数量较(jiao)少；后(hou)者占绝大多数，以(yi)捕食(shi)蚜(ya)(ya)(ya)虫(chong)(chong)、粉虱等(deng)农业害(hai)(hai)虫(chong)(chong)为(wei)主。七(qi)星(xing)瓢(piao)虫(chong)(chong)是肉食(shi)性(xing)瓢(piao)虫(chong)(chong)的(de)一种(zhong)，它体长不(bu)足七(qi)毫米，呈卵圆(yuan)形；背部(bu)拱起似半球，头(tou)黑色，顶端有(you)两(liang)个淡黄(huang)色斑纹，前(qian)胸(xiong)黑色，足黑色，密生细(xi)毛。鞘翅红色或橙黄(huang)色，上面有(you)七(qi)个黑斑，所以(yi)叫七(qi)星(xing)瓢(piao)虫(chong)(chong)。它是捕食(shi)蚜(ya)(ya)(ya)虫(chong)(chong)的(de)好(hao)手，特别喜欢(huan)吃(chi)棉蚜(ya)(ya)(ya)、麦(mai)蚜(ya)(ya)(ya)、菜蚜(ya)(ya)(ya)、桃蚜(ya)(ya)(ya)。一只七(qi)星(xing)瓢(piao)虫(chong)(chong)一天可以(yi)吃(chi)掉(diao)一百三十多只蚜(ya)(ya)(ya)虫(chong)(chong)，所以(yi)农业科(ke)学家常常用它来治虫(chong)(chong)。