七(qi)星瓢(piao)蟲(學名:Coccinella septempunctata)是瓢(piao)蟲科(ke)、瓢(piao)蟲屬(shu)昆蟲。成(cheng)蟲體長5.2-6.5毫米(mi),寬4.0-5.6毫米(mi);身體卵(luan)圓形,背部拱起,呈水瓢(piao)狀;頭黑(hei)(hei)(hei)色(se)(se)、復眼黑(hei)(hei)(hei)色(se)(se),內側(ce)凹入處(chu)各有(you)(you)(you)(you)一淡(dan)黃色(se)(se)點;觸角褐色(se)(se);口(kou)器黑(hei)(hei)(hei)色(se)(se);上額外側(ce)為黃色(se)(se);前胸(xiong)背板黑(hei)(hei)(hei),前上角各有(you)(you)(you)(you)1個(ge)較大(da)的(de)(de)(de)近方(fang)形的(de)(de)(de)淡(dan)黃地;小盾片(pian)黑(hei)(hei)(hei)色(se)(se);鞘(qiao)翅紅色(se)(se)或橙(cheng)黃色(se)(se),兩側(ce)共有(you)(you)(you)(you)7個(ge)黑(hei)(hei)(hei)斑,左右兩側(ce)各有(you)(you)(you)(you)3個(ge)黑(hei)(hei)(hei)點,接合處(chu)前方(fang)尚有(you)(you)(you)(you)一個(ge)更大(da)的(de)(de)(de)黑(hei)(hei)(hei)點;翅基部在小盾片(pian)兩側(ce)各有(you)(you)(you)(you)1個(ge)三角形白斑;體腹及足黑(hei)(hei)(hei)色(se)(se)。
七星瓢(piao)(piao)蟲(chong)(chong)(chong)(chong)一(yi)生(sheng)要經過卵、幼蟲(chong)(chong)(chong)(chong)、蛹和(he)成蟲(chong)(chong)(chong)(chong)4個不(bu)同發(fa)育階段(duan),各蟲(chong)(chong)(chong)(chong)態的(de)發(fa)育歷期,主要受食(shi)(shi)(shi)物(wu)和(he)溫度的(de)影響。七星瓢(piao)(piao)蟲(chong)(chong)(chong)(chong)是(shi)遷飛性昆(kun)蟲(chong)(chong)(chong)(chong),成蟲(chong)(chong)(chong)(chong)和(he)幼蟲(chong)(chong)(chong)(chong)的(de)覓食(shi)(shi)(shi)行(xing)為(wei)屬于廣域搜(sou)索與(yu)區域集中搜(sou)索行(xing)為(wei)的(de)轉換。七星瓢(piao)(piao)蟲(chong)(chong)(chong)(chong)主要以(yi)蚜(ya)蟲(chong)(chong)(chong)(chong)為(wei)食(shi)(shi)(shi),有(you)時還(huan)取食(shi)(shi)(shi)小土粒(li)、真菌孢子和(he)一(yi)些小型昆(kun)蟲(chong)(chong)(chong)(chong),秋天還(huan)常常取食(shi)(shi)(shi)植物(wu)的(de)花粉。廣泛分布于非洲、歐洲、亞洲。
七(qi)星(xing)瓢(piao)蟲的(de)名稱由(you)其(qi)鞘翅上的(de)7個黑色(se)斑點而來(lai),但(dan)是其(qi)身上的(de)斑點數量(liang)是各不相同(tong)的(de)。
七星瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)與異色(se)(se)瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)相似。區別在于(yu)七星瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)淡藍灰色(se)(se),異色(se)(se)瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)灰黑(hei)色(se)(se)。七星瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)腹(fu)部(bu)背(bei)面(mian)和側面(mian),每(mei)節(jie)生有六(liu)個(ge)(ge)短(duan)(duan)刺(ci)(ci);第(di)一(yi)、四兩(liang)(liang)節(jie)背(bei)面(mian)兩(liang)(liang)側,各有一(yi)對黃色(se)(se)短(duan)(duan)刺(ci)(ci);其(qi)余各節(jie)短(duan)(duan)刺(ci)(ci)皆為黑(hei)色(se)(se)。異色(se)(se)瓢蟲(chong)(chong)(chong)(chong)幼蟲(chong)(chong)(chong)(chong)腹(fu)部(bu)背(bei)面(mian)兩(liang)(liang)側,每(mei)節(jie)生有六(liu)個(ge)(ge)分枝的(de)(de)枝刺(ci)(ci),第(di)四兩(liang)(liang)節(jie)的(de)(de)背(bei)面(mian)兩(liang)(liang)側,各有一(yi)對桔(jie)(jie)紅色(se)(se)枝刺(ci)(ci),其(qi)中第(di)一(yi)節(jie)的(de)(de)兩(liang)(liang)個(ge)(ge)枝刺(ci)(ci)基(ji)部(bu)相連(lian),形(xing)成一(yi)個(ge)(ge)桔(jie)(jie)紅色(se)(se)大(da)斑。
某(mou)些金花蟲(chong)(chong)類的(de)卵(luan)(luan),如柳(liu)(liu)葉(xie)(xie)甲(jia)的(de)卵(luan)(luan)和七(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)的(de)卵(luan)(luan)很相似,常被誤認為(wei)七(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)卵(luan)(luan),但(dan)兩者是有明顯區別的(de):①兩者產(chan)卵(luan)(luan)習性不同,柳(liu)(liu)葉(xie)(xie)甲(jia)常在(zai)(zai)柳(liu)(liu)葉(xie)(xie)上(shang)產(chan)卵(luan)(luan),而七(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)通常不在(zai)(zai)樹葉(xie)(xie)上(shang)產(chan)卵(luan)(luan);②柳(liu)(liu)葉(xie)(xie)甲(jia)卵(luan)(luan)粒是長圓形,卵(luan)(luan)塊(kuai)排(pai)列疏(shu)松而不整(zheng)(zheng)齊,七(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)的(de)卵(luan)(luan)粒是梭(suo)形,排(pai)列緊密而整(zheng)(zheng)齊。
七星瓢蟲廣泛分布于北(bei)(bei)美洲、歐洲、亞洲。在中國分布于東北(bei)(bei)、華(hua)北(bei)(bei)、華(hua)中、西北(bei)(bei)、華(hua)東和(he)西南地區。
中(zhong)文(wen)名(ming)(ming) 拉(la)丁學名(ming)(ming) 命名(ming)(ming)者及(ji)年代
七星瓢蟲日本亞(ya)種 Coccinella septempunctata brucki Mulsant,1866
七星瓢蟲指名亞種 Coccinella septempunctata septempunctata Linnaeus,1758
七星瓢(piao)蟲(chong)體(ti)長5.2-7.0毫米,寬4.0-5.6毫米。蟲(chong)體(ti)卵圓形,背面光滑并(bing)拱超呈半球狀。剛羽化的成(cheng)蟲(chong)柔(rou)軟,嫩黃(huang)色(se)(se),2-3小時(shi)后,整(zheng)個體(ti)軀和(he)鞘翅變硬,顏色(se)(se)由黃(huang)變紅,同時(shi)鞘翅上出(chu)現7個黑色(se)(se)斑點。
七(qi)星(xing)瓢蟲和(he)其它昆蟲一(yi)(yi)樣,體軀分為頭(tou)、胸(xiong)(xiong)、腹(fu)三部(bu)分。各部(bu)分均(jun)由(you)若(ruo)干個(ge)(ge)體節(jie)(jie)組成(cheng)。頭(tou)部(bu)生(sheng)(sheng)有(you)(you)一(yi)(yi)對(dui)(dui)觸角,一(yi)(yi)對(dui)(dui)復(fu)眼(yan)和(he)口器(qi),口器(qi)兩(liang)側(ce)有(you)(you)一(yi)(yi)對(dui)(dui)下顎須(xu)。頭(tou)部(bu)較小(xiao),經常(chang)后(hou)縮在發達(da)的(de)前(qian)胸(xiong)(xiong)背(bei)板(ban)之(zhi)下,胸(xiong)(xiong)部(bu)生(sheng)(sheng)有(you)(you)兩(liang)對(dui)(dui)翅(chi),三對(dui)(dui)足(zu)。腹(fu)部(bu)八節(jie)(jie),但(dan)腹(fu)面只能看到6一(yi)(yi)7節(jie)(jie)。腹(fu)部(bu)末(mo)端有(you)(you)外生(sheng)(sheng)殖器(qi)和(he)肛門(men)。胸(xiong)(xiong)部(bu)和(he)腹(fu)部(bu)側(ce)面生(sheng)(sheng)有(you)(you)氣孔,是呼吸時(shi)氣體進出的(de)通道,七(qi)星(xing)瓢蟲和(he)許多(duo)有(you)(you)硬翅(chi)鞘的(de)昆蟲(分類學(xue)上(shang)稱鞘翅(chi)目)一(yi)(yi)樣,有(you)(you)一(yi)(yi)對(dui)(dui)角質堅硬的(de)前(qian)翅(chi)。平時(shi),這(zhe)一(yi)(yi)對(dui)(dui)的(de)翅(chi)并(bing)合(he),覆蓋在胸(xiong)(xiong)腹(fu)部(bu)的(de)背(bei)上(shang)。后(hou)翅(chi)為半透明的(de)膜質,平時(shi)折(zhe)疊,匿于前(qian)翅(chi)之(zhi)下。七(qi)星(xing)瓢蟲的(de)下顎須(xu)末(mo)節(jie)(jie)呈斧(fu)狀,足(zu)的(de)咐節(jie)(jie)是四節(jie)(jie),但(dan)第(di)三節(jie)(jie)特(te)別(bie)小(xiao),并(bing)匿于第(di)二節(jie)(jie)的(de)兩(liang)個(ge)(ge)分葉之(zhi)間,粗看很象是三節(jie)(jie)。
七星(xing)瓢(piao)蟲(chong)雌雄形態,斑紋相同,雌蟲(chong)常較雄蟲(chong)大(da)些。兩者可靠的鑒別特(te)征是雄蟲(chong)腹(fu)部腹(fu)面(mian)末端,有(you)一小的橫的凹陷,而(er)雌蟲(chong)則平坦(tan)而(er)光滑,無(wu)此凹陷。
七(qi)星(xing)瓢蟲(chong)(chong)(chong)幼(you)蟲(chong)(chong)(chong)體表有(you)一(yi)(yi)層較堅硬的表皮,它(ta)的伸展性(xing)有(you)限(xian),所以(yi)生長(chang)到一(yi)(yi)定階(jie)段,必須(xu)蛻(tui)去老(lao)皮,著(zhu)生新皮,才能(neng)繼續成長(chang)。每蛻(tui)一(yi)(yi)次皮,就(jiu)增加一(yi)(yi)個(ge)齡(ling)期,幼(you)蟲(chong)(chong)(chong)共蛻(tui)三次皮,有(you)四(si)個(ge)齡(ling)期。初孵(fu)幼(you)蟲(chong)(chong)(chong)(一(yi)(yi)齡(ling))身(shen)體很(hen)小,只有(you)2-3毫米,孵(fu)化后(hou)(hou),就(jiu)聚集在(zai)原(yuan)卵塊的殘殼上(shang),約(yue)經8-12小時(shi),開始分散取(qu)食。約(yue)兩(liang)天后(hou)(hou),蛻(tui)皮變為二齡(ling),此時(shi)體長(chang)已增大一(yi)(yi)倍多(duo),腹部第一(yi)(yi)節背(bei)面(mian)兩(liang)側(ce),出現兩(liang)個(ge)黃色肉瘤(liu)(liu),三齡(ling)幼(you)蟲(chong)(chong)(chong)除體長(chang)加大外,腹部第一(yi)(yi)、四(si)兩(liang)節的背(bei)面(mian)兩(liang)側(ce),各(ge)有(you)一(yi)(yi)對黃色肉瘤(liu)(liu),但第四(si)節的肉瘤(liu)(liu)不(bu)很(hen)明顯,要用放(fang)大鏡才能(neng)看清楚,到四(si)齡(ling)時(shi),這兩(liang)對肉瘤(liu)(liu)都非常明顯。當幼(you)蟲(chong)(chong)(chong)老(lao)熟時(shi),體形變粗,最(zui)后(hou)(hou)以(yi)尾端固著(zhu)在(zai)植株等(deng)附著(zhu)物上(shang),準備化蛹。
體長7毫米,寬(kuan)5毫米。體黃色。前胸(xiong)背(bei)板前緣有4個(ge)黑(hei)(hei)點(dian),中央2個(ge)呈(cheng)三角形,前胸(xiong)背(bei)板后緣中央有2個(ge)黑(hei)(hei)點(dian),兩側角有2個(ge)黑(hei)(hei)斑。中胸(xiong)背(bei)板有2個(ge)黑(hei)(hei)斑。腹部第2-6節背(bei)面左右有4個(ge)黑(hei)(hei)斑。腹末帶有末齡幼蟲的(de)黑(hei)(hei)色蛻皮。
七(qi)星(xing)(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)的(de)(de)下(xia)(xia)顎(e)須是它(ta)的(de)(de)主要觸(chu)覺和嗅覺器官。七(qi)星(xing)(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)經常(chang)在蚜(ya)蟲(chong)(chong)(chong)(chong)的(de)(de)寄主植物上(shang)爬(pa)動、搜索(suo),當下(xia)(xia)顎(e)須觸(chu)到(dao)蚜(ya)蟲(chong)(chong)(chong)(chong)時,能迅速地用上(shang)顎(e)咬(yao)(yao)住(zhu),將(jiang)(jiang)蚜(ya)蟲(chong)(chong)(chong)(chong)吞食(shi)。如果下(xia)(xia)顎(e)須沒有(you)觸(chu)到(dao),即使蚜(ya)蟲(chong)(chong)(chong)(chong)就在它(ta)的(de)(de)眼前,似(si)乎也(ye)不能發(fa)現。七(qi)星(xing)(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)成蟲(chong)(chong)(chong)(chong)和幼(you)蟲(chong)(chong)(chong)(chong)雖都取(qu)(qu)(qu)食(shi)蚜(ya)蟲(chong)(chong)(chong)(chong),但(dan)因(yin)蟲(chong)(chong)(chong)(chong)態不同(tong)(tong),口器結構不同(tong)(tong),取(qu)(qu)(qu)食(shi)方法也(ye)有(you)差(cha)別(bie)。成蟲(chong)(chong)(chong)(chong)取(qu)(qu)(qu)食(shi)時,通(tong)常(chang)將(jiang)(jiang)蚜(ya)蟲(chong)(chong)(chong)(chong)咬(yao)(yao)住(zhu),經過口器的(de)(de)簡單咀嚼后,將(jiang)(jiang)蚜(ya)蟲(chong)(chong)(chong)(chong)軀體(ti)、附肢等(deng)完全吞下(xia)(xia)。大(da)齡幼(you)蟲(chong)(chong)(chong)(chong)取(qu)(qu)(qu)食(shi)基本上(shang)和成蟲(chong)(chong)(chong)(chong)一(yi)樣。但(dan)初齡幼(you)蟲(chong)(chong)(chong)(chong)因(yin)口器小(xiao),吞食(shi)力差(cha),取(qu)(qu)(qu)食(shi)時常(chang)在蚜(ya)蟲(chong)(chong)(chong)(chong)體(ti)上(shang)咬(yao)(yao)一(yi)個孔(kong),吸食(shi)汁液,最后留下(xia)(xia)蚜(ya)體(ti)殘(can)殼。一(yi)頭七(qi)星(xing)(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)的(de)(de)成蟲(chong)(chong)(chong)(chong),平均一(yi)天吃(chi)棉蚜(ya)100-120頭,吃(chi)菜蚜(ya)147頭,吃(chi)杏蚜(ya)59頭。幼(you)蟲(chong)(chong)(chong)(chong)食(shi)蚜(ya)量則因(yin)齡期的(de)(de)大(da)小(xiao)而(er)不同(tong)(tong),齡期小(xiao)吃(chi)的(de)(de)少(shao),齡期大(da)吃(chi)的(de)(de)多。
七星瓢蟲(chong)(chong)有吃(chi)(chi)(chi)卵(luan)和互相捕食(shi)的(de)習(xi)性。在食(shi)物不足(zu)的(de)情況下,七星瓢蟲(chong)(chong)成蟲(chong)(chong)很(hen)容易吃(chi)(chi)(chi)掉已產下的(de)卵(luan)塊(kuai)。即使(shi)有充足(zu)的(de)蚜蟲(chong)(chong),它(ta)們也(ye)喜歡吃(chi)(chi)(chi)卵(luan);幼蟲(chong)(chong)則常(chang)互相捕食(shi)。同一卵(luan)塊(kuai)早孵出的(de)個體,常(chang)吃(chi)(chi)(chi)掉尚未孵化(hua)的(de)卵(luan)粒。大齡(ling)幼蟲(chong)(chong)常(chang)吃(chi)(chi)(chi)掉小(xiao)齡(ling)幼蟲(chong)(chong)。蛹(yong)也(ye)常(chang)被成蟲(chong)(chong)和大齡(ling)幼蟲(chong)(chong)吃(chi)(chi)(chi)掉。
七星(xing)(xing)瓢(piao)蟲(chong)雖然主要(yao)是吃蚜(ya)蟲(chong),但并(bing)不僅(jin)僅(jin)限于以(yi)蚜(ya)蟲(chong)為(wei)食(shi)(shi)。中(zhong)國北京的金山腳下(xia)(xia),在(zai)秋(qiu)(qiu)天蒿草(cao)和(he)荊條(tiao)上并(bing)沒有蚜(ya)蟲(chong),七星(xing)(xing)瓢(piao)蟲(chong)成(cheng)蟲(chong)卻群集(ji)其上,數(shu)量很(hen)多。經過仔(zi)細觀(guan)察和(he)消化道解削并(bing)在(zai)顯微鏡下(xia)(xia)檢查,發(fa)現(xian)七星(xing)(xing)瓢(piao)蟲(chong)在(zai)早春不僅(jin)吃蚜(ya)蟲(chong),還(huan)取食(shi)(shi)小土粒、真菌孢子和(he)一些小型昆(kun)蟲(chong)。秋(qiu)(qiu)天,七星(xing)(xing)瓢(piao)蟲(chong)則(ze)常(chang)常(chang)取食(shi)(shi)植物的花粉。
七星瓢蟲(chong)一(yi)生(sheng)經過(guo)卵(luan)、幼(you)蟲(chong)、蛹、成蟲(chong)等四(si)個發(fa)育(yu)(yu)(yu)(yu)階段。七星瓢蟲(chong)各蟲(chong)態(tai)的發(fa)育(yu)(yu)(yu)(yu)歷期(qi),主要(yao)受(shou)食(shi)(shi)物和溫(wen)度(du)(du)的影(ying)響。在適(shi)宜的食(shi)(shi)物條件(jian)下,溫(wen)度(du)(du)不(bu)同(tong),發(fa)育(yu)(yu)(yu)(yu)的速(su)率也不(bu)相同(tong)。幼(you)蟲(chong)期(qi)在15℃條件(jian)下,長(chang)達44.1天(tian)(tian),而在24-26℃時(shi)只有(you)8-9.4天(tian)(tian)。高于30℃發(fa)育(yu)(yu)(yu)(yu)速(su)率又逐漸(jian)降低,33℃時(shi)幼(you)蟲(chong)期(qi)又延長(chang)到16.2天(tian)(tian)。溫(wen)度(du)(du)不(bu)適(shi)宜時(shi)發(fa)育(yu)(yu)(yu)(yu)緩(huan)慢的原因,除直接(jie)受(shou)溫(wen)度(du)(du)影(ying)響外,取食(shi)(shi)速(su)率低也有(you)關(guan)系。一(yi)頭四(si)齡幼(you)蟲(chong)在25℃左右時(shi),每天(tian)(tian)取食(shi)(shi)一(yi)百多(duo)頭蚜蟲(chong),而在15℃時(shi),僅取食(shi)(shi)十幾頭。
七(qi)(qi)星(xing)(xing)瓢蟲(chong)以成蟲(chong)越冬,多選擇較干燥、溫(wen)暖的(de)(de)枯枝落(luo)葉(xie)下、雜(za)草基部近地面的(de)(de)土塊下、土縫(feng)中、樹皮裂縫(feng)處潛伏,蟄(zhe)伏越冬后(hou),若遇溫(wen)度回暖,又(you)爬出越冬場所活(huo)動。出蟄(zhe)后(hou)的(de)(de)七(qi)(qi)星(xing)(xing)瓢蟲(chong)迅速在林(lin)木、雜(za)草和(he)作物之間活(huo)動,特(te)別是帶蚜蟲(chong)的(de)(de)作物與開花(hua)果木上。七(qi)(qi)星(xing)(xing)瓢蟲(chong)是遷飛性(xing)昆蟲(chong),成蟲(chong)和(he)幼蟲(chong)的(de)(de)覓食行為屬于(yu)廣域搜索與區(qu)域集中搜索行為的(de)(de)轉換。
七星瓢蟲有(you)著驚人(ren)的避敵(di)本領(ling)。只要有(you)天敵(di)來擾或受(shou)(shou)到外界突然(ran)的刺激,它(ta)(ta)就會(hui)發生一種(zhong)叫做“神(shen)經休克(ke)”現象,有(you)點像失去知覺似(si)的一動不動。“休克(ke)”過后,受(shou)(shou)到刺激的神(shen)經系統恢復(fu)正常(chang),它(ta)(ta)又清醒(xing)過來,開始爬(pa)行。這(zhe)種(zhong)“死去活來”的舉止,人(ren)們稱它(ta)(ta)“假死”。如果用(yong)手(shou)去捏它(ta)(ta),它(ta)(ta)就會(hui)使(shi)出第二招避敵(di)本領(ling),在它(ta)(ta)6條(tiao)足上的各(ge)關節中間,滲出一種(zhong)黃色汁液(ye)來,這(zhe)些汁液(ye)散發出來的辣(la)臭味,可使(shi)人(ren)聞(wen)之感到膩煩,就連鳥類聞(wen)到這(zhe)種(zhong)怪味,也“退避三舍”。
七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)在(zai)不同季節的(de)(de)(de)活動(dong)場所不一樣。冬(dong)天,七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)在(zai)小麥和(he)(he)油菜(cai)的(de)(de)(de)根莖間越冬(dong),也有的(de)(de)(de)在(zai)向(xiang)陽的(de)(de)(de)土塊、土縫中過冬(dong)。春天,一旦(dan)氣(qi)(qi)溫升到10℃以上(shang)(shang),越冬(dong)的(de)(de)(de)七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)就蘇醒過來(lai),開始活動(dong),在(zai)麥類(lei)和(he)(he)油菜(cai)植物(wu)株上(shang)(shang)能找到它。夏天,隨(sui)著(zhu)氣(qi)(qi)溫升高(gao)和(he)(he)食物(wu)增多(duo),七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)大(da)量繁殖,凡(fan)是有蚜蟲(chong)(chong)和(he)(he)蚧蟲(chong)(chong)寄(ji)生的(de)(de)(de)植物(wu),如棉(mian)花、柳樹、槐樹、榆樹、豆(dou)類(lei)等植株上(shang)(shang),都能找到七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong),有時甚至出現大(da)批七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)聚集的(de)(de)(de)景象。秋天,田間七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)的(de)(de)(de)數(shu)量減少(shao),它常在(zai)玉米、蘿卜和(he)(he)白菜(cai)等處產(chan)卵,這時候,早晚的(de)(de)(de)氣(qi)(qi)溫較低(di),七(qi)(qi)(qi)(qi)星(xing)(xing)(xing)(xing)(xing)瓢(piao)(piao)(piao)(piao)蟲(chong)(chong)往往隱蔽起(qi)來(lai),不易發現,需在(zai)上(shang)(shang)午7點(dian)鐘以后至太陽下山(shan)之前采集。
越冬的(de)七(qi)星瓢(piao)蟲(chong)不食(shi)不動(dong),只要(yao)找(zhao)到,捕捉很方便,用(yong)手(shou)就(jiu)(jiu)能捉住。其他季(ji)節的(de)七(qi)星瓢(piao)蟲(chong)善爬能飛,可(ke)以(yi)利用(yong)它假(jia)死習性,用(yong)塑料袋(dai)(dai)迅(xun)速(su)套住棲息著七(qi)星瓢(piao)蟲(chong)的(de)枝條(tiao),抖動(dong)一下,七(qi)星瓢(piao)蟲(chong)立即掉(diao)落在袋(dai)(dai)里,接著,把(ba)枝條(tiao)抽出,扎緊(jin)口袋(dai)(dai),就(jiu)(jiu)可(ke)以(yi)帶回實(shi)驗室。
人(ren)工(gong)飼養(yang)七星(xing)瓢蟲(chong),首先要解決飼料(liao)(liao)問題。可(ke)以到野(ye)外(wai)(wai)采集天(tian)然飼料(liao)(liao)蚜(ya)(ya)(ya)蟲(chong),但這(zhe)種(zhong)方(fang)法費工(gong)多,有時(shi)還不易采到。所以用(yong)人(ren)工(gong)培養(yang)大量(liang)蚜(ya)(ya)(ya)蟲(chong),滿足七星(xing)瓢蟲(chong)食用(yong)。可(ke)用(yong)蠶豆苗人(ren)工(gong)培養(yang)蚜(ya)(ya)(ya)蟲(chong)。當分栽(zai)的(de)蠶豆苗長出3-4厘(li)米高時(shi),把野(ye)外(wai)(wai)采集的(de)少量(liang)蚜(ya)(ya)(ya)蟲(chong)放在豆苗上(shang),在室(shi)溫(wen)20-30℃、相對濕度60-70%的(de)條件下培養(yang)10-15天(tian),蚜(ya)(ya)(ya)蟲(chong)就能(neng)大量(liang)繁殖,這(zhe)時(shi)就可(ke)用(yong)蚜(ya)(ya)(ya)蟲(chong)作七星(xing)瓢蟲(chong)的(de)飼料(liao)(liao)。
將蛹或成蟲(chong)放入成蟲(chong)飼養(yang)(yang)籠(long)(long)(long)(long)(long)內(nei),每(mei)籠(long)(long)(long)(long)(long)放雌蟲(chong)500-750頭(tou),并搭配1/4的(de)(de)雄(xiong)蟲(chong)。成蟲(chong)喂人工(gong)飼料(liao)或蚜蟲(chong),每(mei)天(tian)(tian)喂飼料(liao)和(he)加水(shui)。新(xin)羽化的(de)(de)成蟲(chong),經過幾天(tian)(tian)的(de)(de)取食,逐步達到性成熟(shu),便(bian)交尾產卵(luan)。產卵(luan)時間(jian)多在晚上(shang)7-9點鐘。卵(luan)產在籠(long)(long)(long)(long)(long)頂和(he)內(nei)側的(de)(de)紙上(shang),收(shou)卵(luan)時,將籠(long)(long)(long)(long)(long)內(nei)的(de)(de)紙取出,換上(shang)新(xin)鮮的(de)(de)紙就成了。收(shou)卵(luan)每(mei)天(tian)(tian)1-2次(ci),同時換飼料(liao)和(he)水(shui)。收(shou)卵(luan)時先準備(bei)一批空飼養(yang)(yang)籠(long)(long)(long)(long)(long),籠(long)(long)(long)(long)(long)底打(da)開(kai),頂面向光,然后將有蟲(chong)的(de)(de)籠(long)(long)(long)(long)(long)底面紗(sha)布拆開(kai),籠(long)(long)(long)(long)(long)底對(dui)準籠(long)(long)(long)(long)(long)底,成蟲(chong)馬上(shang)向有光的(de)(de)方向集中,進入新(xin)的(de)(de)籠(long)(long)(long)(long)(long)內(nei)。
成(cheng)蟲飼養時(shi),如食料不足,就不產(chan)卵(luan)。成(cheng)蟲在黑暗條件下活躍,晚上可適當(dang)加光照,減少成(cheng)蟲活動(dong),避免相互碰傷。
七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong)大(da)量繁殖(zhi)后(hou),可以(yi)放(fang)(fang)(fang)(fang)(fang)到(dao)田(tian)間,幫助(zhu)人類消滅蚜(ya)蟲(chong)(chong)(chong)(chong)(chong)和(he)蚧蟲(chong)(chong)(chong)(chong)(chong)。如棉(mian)田(tian)出現大(da)量蚜(ya)蟲(chong)(chong)(chong)(chong)(chong)危害,這時(shi)可以(yi)把七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong)散(san)放(fang)(fang)(fang)(fang)(fang)到(dao)棉(mian)田(tian)里,它(ta)(ta)就(jiu)能(neng)將(jiang)蚜(ya)蟲(chong)(chong)(chong)(chong)(chong)吃掉(diao)。散(san)發時(shi),在棉(mian)田(tian)邊走邊放(fang)(fang)(fang)(fang)(fang)七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong),走幾步放(fang)(fang)(fang)(fang)(fang)幾只,以(yi)求散(san)放(fang)(fang)(fang)(fang)(fang)均勻:①掌握好(hao)散(san)放(fang)(fang)(fang)(fang)(fang)時(shi)間,以(yi)傍(bang)晚(wan)時(shi)散(san)放(fang)(fang)(fang)(fang)(fang)為(wei)(wei)宜(yi)。因為(wei)(wei)傍(bang)晚(wan)氣溫較(jiao)低,光線較(jiao)暗,七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong)活動性較(jiao)弱,不(bu)(bu)易遷飛(fei);②采(cai)用成蟲(chong)(chong)(chong)(chong)(chong)和(he)幼蟲(chong)(chong)(chong)(chong)(chong)混放(fang)(fang)(fang)(fang)(fang)。因為(wei)(wei)幼蟲(chong)(chong)(chong)(chong)(chong)沒有遷飛(fei)能(neng)力,不(bu)(bu)會逃逸,而它(ta)(ta)也(ye)有吃蚜(ya)蟲(chong)(chong)(chong)(chong)(chong)的本(ben)領;③散(san)發前一天停止喂(wei)食,再進行散(san)放(fang)(fang)(fang)(fang)(fang),可以(yi)降(jiang)低七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong)遷飛(fei)活動能(neng)力;④散(san)放(fang)(fang)(fang)(fang)(fang)后(hou)兩(liang)天內,不(bu)(bu)進行中耕(geng)和(he)其他(ta)田(tian)間管理,以(yi)免使七(qi)(qi)(qi)星(xing)瓢(piao)蟲(chong)(chong)(chong)(chong)(chong)受驚遷逃。
七星瓢蟲(chong)卵(luan)(luan)通常成塊地產在(zai)莖葉或土(tu)塊上。卵(luan)(luan)粒(li)梭形,豎立,整齊地排列成塊。每(mei)個卵(luan)(luan)塊一(yi)般30粒(li)左右。最多可達(da)百余粒(li),少的(de)則僅有幾粒(li)。剛產下(xia)的(de)卵(luan)(luan)淡黃色(se),后逐(zhu)漸變為杏(xing)黃色(se)。將孵化時,呈黑渴(ke)色(se)。
新羽化的七(qi)星(xing)瓢蟲(chong)(chong)成蟲(chong)(chong),待體軀(qu)和(he)翅鞘硬(ying)化后(hou),便(bian)開(kai)(kai)(kai)始活動取(qu)食(shi),3-4天后(hou)交(jiao)尾。七(qi)星(xing)瓢蟲(chong)(chong)有多次交(jiao)尾習性,但經(jing)一次交(jiao)尾,雌(ci)蟲(chong)(chong)所產(chan)的卵(luan)(luan)(luan)(luan)就(jiu)都能孵化。秋季越(yue)冬代成蟲(chong)(chong)交(jiao)尾后(hou),雖活動取(qu)食(shi),但卵(luan)(luan)(luan)(luan)巢并不(bu)發育,翌春活動取(qu)食(shi)后(hou)才開(kai)(kai)(kai)始產(chan)卵(luan)(luan)(luan)(luan)。非越(yue)冬代成蟲(chong)(chong)交(jiao)尾3-5天后(hou),便(bian)開(kai)(kai)(kai)始產(chan)卵(luan)(luan)(luan)(luan)。產(chan)卵(luan)(luan)(luan)(luan)開(kai)(kai)(kai)始以后(hou),幾(ji)天內就(jiu)達到了(le)高峰,產(chan)卵(luan)(luan)(luan)(luan)盛(sheng)期持(chi)續一個月左右。在盛(sheng)期的33天里(li),產(chan)下了(le)全部(bu)卵(luan)(luan)(luan)(luan)粒的95%以上(shang)。產(chan)卵(luan)(luan)(luan)(luan)盛(sheng)期,一頭雌(ci)蟲(chong)(chong)一天可(ke)產(chan)好幾(ji)個卵(luan)(luan)(luan)(luan)塊。七(qi)星(xing)瓢蟲(chong)(chong)因取(qu)食(shi)的蚜(ya)蟲(chong)(chong)種(zhong)類不(bu)同,產(chan)卵(luan)(luan)(luan)(luan)量(liang)大小(xiao)也不(bu)同。取(qu)食(shi)它喜歡吃(chi)的蚜(ya)蟲(chong)(chong)時(shi),產(chan)卵(luan)(luan)(luan)(luan)量(liang)就(jiu)大,取(qu)食(shi)不(bu)害歡吃(chi)的蚜(ya)蟲(chong)(chong)時(shi),產(chan)卵(luan)(luan)(luan)(luan)量(liang)就(jiu)小(xiao)。
七星瓢蟲卵期(qi)長(chang)短和溫度有(you)關系,當16-17℃時,卵期(qi)8天,24-26℃時,卵期(qi)僅2-3天。七星瓢蟲成(cheng)蟲壽命因世代不同(tong)而有(you)較(jiao)大差異。越冬代成(cheng)蟲壽命一(yi)般都(dou)較(jiao)長(chang),可(ke)達8-10個月,非越冬代成(cheng)蟲一(yi)般可(ke)活(huo)2-3個月。
七星瓢蟲的(de)(de)生(sheng)殖(zhi)滯育(yu)(yu)突出地表現于(yu)2個方面:①種群中產卵(luan)(luan)(luan)雌(ci)蟲所(suo)(suo)占的(de)(de)比(bi)例(li),簡稱為(wei)(wei)產卵(luan)(luan)(luan)率,無滯育(yu)(yu)時(shi)達(da)100%;如越冬后蚜蟲充足時(shi)便(bian)是如此。而其(qi)(qi)第二代則因有生(sheng)殖(zhi)滯育(yu)(yu),產卵(luan)(luan)(luan)率下降。②成(cheng)蟲羽化后產卵(luan)(luan)(luan)前期延長的(de)(de)程度,這(zhe)(zhe)主要由卵(luan)(luan)(luan)巢發(fa)育(yu)(yu)緩(huan)慢或暫(zan)時(shi)停頓所(suo)(suo)造成(cheng)。顯(xian)示(shi)出這(zhe)(zhe)種差異的(de)(de)是雌(ci)蟲。而雄蟲在滯育(yu)(yu)期間(jian)其(qi)(qi)行(xing)為(wei)(wei)、趨性(xing)和生(sheng)殖(zhi)附腺的(de)(de)分泌活動雖(sui)與生(sheng)殖(zhi)期有所(suo)(suo)不同,但仍(reng)可交(jiao)尾,睪(gao)丸(wan)中有成(cheng)熟精子。雌(ci)蟲滯育(yu)(yu)時(shi)卵(luan)(luan)(luan)巢管停止于(yu)原(yuan)(yuan)卵(luan)(luan)(luan)區階段,濾泡不進(jin)行(xing)發(fa)育(yu)(yu)。這(zhe)(zhe)時(shi)咽側體及其(qi)(qi)細胞體積(ji)均小(xiao),無合(he)成(cheng)保幼激(ji)素(su)的(de)(de)活性(xing)。體內積(ji)累(lei)較(jiao)多的(de)(de)營養物質,脂肪體雖(sui)很發(fa)達(da),但不合(he)成(cheng)卵(luan)(luan)(luan)黃原(yuan)(yuan)蛋白。
早春田(tian)間采(cai)集的(de)(de)(de)越冬代七星瓢蟲(chong),因其發(fa)育階段不同,一(yi)般采(cai)回(hui)飼養(yang)1-7天(tian)后(hou)即開始產(chan)(chan)卵(luan)(luan)(luan)(luan)。瓢蟲(chong)產(chan)(chan)卵(luan)(luan)(luan)(luan)沒有固定(ding)的(de)(de)(de)時間,產(chan)(chan)卵(luan)(luan)(luan)(luan)的(de)(de)(de)地(di)點也沒有嚴(yan)格的(de)(de)(de)選擇性,在(zai)(zai)(zai)盒(he)壁及植物上(shang)(shang)都可產(chan)(chan)卵(luan)(luan)(luan)(luan),為了集卵(luan)(luan)(luan)(luan)的(de)(de)(de)方(fang)便,可以裁一(yi)長(chang)22厘(li)米、寬5厘(li)米的(de)(de)(de)薄紙(zhi),卷成紙(zhi)筒(tong),襯(chen)在(zai)(zai)(zai)紙(zhi)盒(he)內或玻璃器(qi)內,使其盡量緊貼在(zai)(zai)(zai)紙(zhi)盒(he)內壁,這樣卵(luan)(luan)(luan)(luan)多產(chan)(chan)在(zai)(zai)(zai)襯(chen)紙(zhi)上(shang)(shang)。采(cai)卵(luan)(luan)(luan)(luan)時,可將襯(chen)紙(zhi)取出,將有卵(luan)(luan)(luan)(luan)粒(li)部(bu)位的(de)(de)(de)紙(zhi)剪(jian)下,放(fang)另外的(de)(de)(de)空紙(zhi)盒(he)中(zhong),然(ran)后(hou)再用紙(zhi)片補(bu)好襯(chen)紙(zhi),仍放(fang)盒(he)內再用。取卵(luan)(luan)(luan)(luan)時應仔細檢查盒(he)內植物上(shang)(shang)有無卵(luan)(luan)(luan)(luan)粒(li),特(te)別在(zai)(zai)(zai)氣候干(gan)燥時,植物常(chang)常(chang)干(gan)縮,卵(luan)(luan)(luan)(luan)粒(li)常(chang)隱(yin)藏其中(zhong),如發(fa)現(xian)卵(luan)(luan)(luan)(luan)粒(li),應將帶有卵(luan)(luan)(luan)(luan)粒(li)的(de)(de)(de)部(bu)位剪(jian)下。如果用瓶(ping)(ping)養(yang),瓢蟲(chong)卵(luan)(luan)(luan)(luan)產(chan)(chan)在(zai)(zai)(zai)瓶(ping)(ping)壁上(shang)(shang),取卵(luan)(luan)(luan)(luan)時可用毛筆(bi)沾少(shao)許清水,將卵(luan)(luan)(luan)(luan)濕潤,經(jing)數秒鐘(zhong)后(hou),再用毛筆(bi)尖輕輕將卵(luan)(luan)(luan)(luan)撥下,放(fang)在(zai)(zai)(zai)涂有少(shao)許稀漿糊的(de)(de)(de)紙(zhi)上(shang)(shang),只要卵(luan)(luan)(luan)(luan)粒(li)保(bao)持完(wan)(wan)整,仍然(ran)正常(chang)孵化。但這樣取卵(luan)(luan)(luan)(luan),很難保(bao)證全部(bu)卵(luan)(luan)(luan)(luan)粒(li)完(wan)(wan)整無損,且(qie)操作費時,因此在(zai)(zai)(zai)大規模飼養(yang)瓢蟲(chong)寸(cun),仍以紙(zhi)盒(he)為宜。
瓢蟲成蟲有取食(shi)卵粒的(de)習性(xing),產(chan)卵后,應及時將卵粒取走。每日取卵的(de)時間,可結(jie)合兩次喂食(shi)同時進行,邊換飼料(liao)、邊取卵。產(chan)卵高峰期,最好能每日取卵三次。
七(qi)星瓢蟲(chong)(chong)的(de)卵是一(yi)粒(li)(li)粒(li)(li)豎(shu)立(li)成排(pai),形(xing)成整齊的(de)卵塊,由飼(si)(si)養(yang)盒(he)中取出以后(hou)堆放在一(yi)起(qi),很(hen)容易彼此摩擦(ca),影響孵化率。七(qi)星瓢蟲(chong)(chong)的(de)卵在20℃時,只需(xu)(xu)5-6天(tian)即可孵化。25℃時只需(xu)(xu)3天(tian)即可孵化。如(ru)果長時間堆放在一(yi)起(qi),不僅降低孵化率,而且幼蟲(chong)(chong)孵化以后(hou),也(ye)不便于收(shou)集飼(si)(si)養(yang)。因(yin)此,每次取出卵粒(li)(li)以后(hou),應(ying)及時進行處理。可通過制(zhi)取卵卡解決(jue)以上問題(ti)。
七星瓢(piao)(piao)蟲(chong)的(de)(de)產卵期(qi)可(ke)(ke)(ke)長達(da)20-30天(tian)(tian),產卵的(de)(de)高(gao)峰(feng)期(qi)亦(yi)有(you)7-10天(tian)(tian),因此(ci),收集的(de)(de)卵塊必須立即進行低(di)(di)溫(wen)(wen)(wen)(wen)保(bao)存(cun)(cun)(cun),以防止逐日孵(fu)化(hua)(hua)不(bu)便(bian)集中(zhong)使(shi)用(yong)。加之自然氣候的(de)(de)變化(hua)(hua)或人工飼養瓢(piao)(piao)蟲(chong)的(de)(de)條件(jian)改變,都會造成瓢(piao)(piao)蟲(chong)的(de)(de)產卵高(gao)峰(feng)期(qi)、卵的(de)(de)孵(fu)化(hua)(hua)期(qi)與田間(jian)蚜蟲(chong)發(fa)生(sheng)的(de)(de)時(shi)間(jian)不(bu)相配(pei)合,也(ye)常需要對卵做低(di)(di)溫(wen)(wen)(wen)(wen)保(bao)存(cun)(cun)(cun)。保(bao)存(cun)(cun)(cun)的(de)(de)時(shi)間(jian)長短,溫(wen)(wen)(wen)(wen)度高(gao)低(di)(di)都有(you)一定的(de)(de)限度。在(zai)0℃時(shi)保(bao)存(cun)(cun)(cun)3天(tian)(tian),其孵(fu)化(hua)(hua)率(lv)仍能達(da)到(dao)70%以上(shang)。超(chao)過3天(tian)(tian),孵(fu)化(hua)(hua)率(lv)大(da)為降低(di)(di)。如在(zai)4℃時(shi),可(ke)(ke)(ke)保(bao)存(cun)(cun)(cun)7天(tian)(tian),孵(fu)化(hua)(hua)率(lv)在(zai)70%以上(shang)。在(zai)11-13℃之間(jian),卵可(ke)(ke)(ke)保(bao)存(cun)(cun)(cun)20天(tian)(tian),其孵(fu)化(hua)(hua)率(lv)仍然達(da)到(dao)80%左右。實驗表明,七星瓢(piao)(piao)蟲(chong)發(fa)育起(qi)點溫(wen)(wen)(wen)(wen)度為10℃左右,低(di)(di)于這(zhe)個溫(wen)(wen)(wen)(wen)度,瓢(piao)(piao)蟲(chong)卵雖(sui)可(ke)(ke)(ke)短時(shi)間(jian)保(bao)存(cun)(cun)(cun),但其成活率(lv)不(bu)高(gao)。如保(bao)存(cun)(cun)(cun)在(zai)發(fa)育起(qi)點溫(wen)(wen)(wen)(wen)度之上(shang),保(bao)存(cun)(cun)(cun)天(tian)(tian)數較長,孵(fu)化(hua)(hua)率(lv)亦(yi)高(gao)。因此(ci),卵的(de)(de)保(bao)存(cun)(cun)(cun)溫(wen)(wen)(wen)(wen)度以10-12℃為宜。
卵(luan)(luan)的(de)孵(fu)(fu)化(hua)(hua)(hua)要(yao)求(qiu)有一定的(de)溫(wen)(wen)濕(shi)度(du)(du)(du)條(tiao)(tiao)(tiao)件(jian)(jian)。在(zai)(zai)發育起點(dian)溫(wen)(wen)度(du)(du)(du)以上(shang),卵(luan)(luan)雖(sui)然可以孵(fu)(fu)化(hua)(hua)(hua),但(dan)其最適宜的(de)溫(wen)(wen)度(du)(du)(du)是(shi)20-25℃,相對濕(shi)度(du)(du)(du)70-80%。因(yin)此在(zai)(zai)卵(luan)(luan)需(xu)(xu)要(yao)孵(fu)(fu)化(hua)(hua)(hua)時(shi),應由貯存處取回,放于室(shi)溫(wen)(wen)中進行。一般在(zai)(zai)棉(mian)(mian)蚜開始(shi)遷飛(fei)棉(mian)(mian)田時(shi),日(ri)平均溫(wen)(wen)度(du)(du)(du)皆在(zai)(zai)15℃左右,均能滿足卵(luan)(luan)的(de)孵(fu)(fu)化(hua)(hua)(hua)溫(wen)(wen)度(du)(du)(du)條(tiao)(tiao)(tiao)件(jian)(jian),孵(fu)(fu)化(hua)(hua)(hua)的(de)關鍵條(tiao)(tiao)(tiao)件(jian)(jian)就在(zai)(zai)于濕(shi)度(du)(du)(du)。如濕(shi)度(du)(du)(du)在(zai)(zai)80%以上(shang),小(xiao)幼蟲很容易(yi)由卵(luan)(luan)殼內孵(fu)(fu)出,但(dan)在(zai)(zai)干燥低濕(shi)的(de)條(tiao)(tiao)(tiao)件(jian)(jian)下,小(xiao)幼蟲常在(zai)(zai)卵(luan)(luan)口處掙扎,不(bu)易(yi)脫出。嚴重時(shi),甚至不(bu)孵(fu)(fu)化(hua)(hua)(hua)。因(yin)此大量的(de)卵(luan)(luan)需(xu)(xu)要(yao)孵(fu)(fu)化(hua)(hua)(hua)時(shi),應創造高濕(shi)條(tiao)(tiao)(tiao)件(jian)(jian)。孵(fu)(fu)化(hua)(hua)(hua)時(shi)可在(zai)(zai)孵(fu)(fu)化(hua)(hua)(hua)室(shi)內地面潑水(shui),掛(gua)濕(shi)布(bu)等(deng),增加室(shi)內濕(shi)度(du)(du)(du);亦可同時(shi)在(zai)(zai)盛放卵(luan)(luan)卡的(de)容器內放濕(shi)棉(mian)(mian)球(qiu),容器頂(ding)部再蓋(gai)以濕(shi)布(bu),增加卵(luan)(luan)卡周圍水(shui)分的(de)蒸發條(tiao)(tiao)(tiao)件(jian)(jian),經過這樣處理以后(hou),卵(luan)(luan)的(de)孵(fu)(fu)化(hua)(hua)(hua)時(shi)間較(jiao)快,孵(fu)(fu)出后(hou)小(xiao)幼蟲生命力較(jiao)強。
卵孵化(hua)時(shi),應加強檢(jian)(jian)查(cha)與(yu)管(guan)理,每日(ri)至少(shao)檢(jian)(jian)查(cha)4次,發現幼蟲孵出(chu)后,應及時(shi)取(qu)出(chu)。在(zai)卵的孵化(hua)高峰時(shi),應3-4小時(shi)檢(jian)(jian)查(cha)一次,并且(qie)要求日(ri)夜有人看管(guan)。