一封是雜草芽前封閉

苗床封閉時間選在棉(mian)(mian)花苗床播種(zhong)覆土后蓋(gai)膜前(qian)(qian)，可選擇的(de)(de)除(chu)(chu)(chu)草(cao)(cao)劑(ji)品(pin)種(zhong)和用(yong)(yong)法：每(mei)667平方米可選用(yong)(yong)90%禾耐(nai)斯（乙草(cao)(cao)胺）乳(ru)油(you)40毫(hao)升(sheng)～50毫(hao)升(sheng)、或50%乙草(cao)(cao)胺乳(ru)油(you)75毫(hao)升(sheng)～9o毫(hao)升(sheng)、或48%拉索（甲(jia)草(cao)(cao)胺）乳(ru)油(you)150毫(hao)升(sheng)～200毫(hao)升(sheng)、或72%都爾(er)乳(ru)油(you)100毫(hao)升(sheng)～200毫(hao)升(sheng)、或24%果爾(er)（乙氧氟(fu)草(cao)(cao)醚）12毫(hao)升(sheng)一18毫(hao)升(sheng)對水噴霧(wu)。大田封閉視棉(mian)(mian)田類型而定，冬(dong)閑田雜(za)草(cao)(cao)多而密，應在棉(mian)(mian)花移栽前(qian)(qian)20天～30天，結合使(shi)用(yong)(yong)草(cao)(cao)甘膦(lin)或百草(cao)(cao)枯類除(chu)(chu)(chu)草(cao)(cao)劑(ji)防除(chu)(chu)(chu)冬(dong)季雜(za)草(cao)(cao)，選用(yong)(yong)上述(shu)芽(ya)前(qian)(qian)除(chu)(chu)(chu)草(cao)(cao)劑(ji)混合使(shi)用(yong)(yong)。對于有前(qian)(qian)茬作(zuo)物的(de)(de)棉(mian)(mian)田，在前(qian)(qian)茬作(zuo)物收獲后，立即選用(yong)(yong)上述(shu)芽(ya)前(qian)(qian)除(chu)(chu)(chu)草(cao)(cao)劑(ji)加(jia)20%百草(cao)(cao)枯類（如克無蹤、一把火）除(chu)(chu)(chu)草(cao)(cao)劑(ji)混合噴施，此時最好(hao)不要用(yong)(yong)草(cao)(cao)甘膦(lin)類除(chu)(chu)(chu)草(cao)(cao)劑(ji)。

二殺是雜草苗后莖葉處理

①在(zai)未使用(yong)芽前(qian)除(chu)草(cao)(cao)(cao)(cao)(cao)劑(ji)(ji)處(chu)(chu)理(li)(li)(li)(li)或(huo)遇(yu)到(dao)干旱天氣芽前(qian)處(chu)(chu)理(li)(li)(li)(li)效果不理(li)(li)(li)(li)想的棉(mian)(mian)(mian)花(hua)苗(miao)(miao)(miao)床或(huo)大田(tian)，當(dang)雜草(cao)(cao)(cao)(cao)(cao)生(sheng)長達(da)(da)到(dao)3葉(xie)期～6葉(xie)期時，進(jin)行(xing)莖(jing)葉(xie)處(chu)(chu)理(li)(li)(li)(li)除(chu)草(cao)(cao)(cao)(cao)(cao)。苗(miao)(miao)(miao)床或(huo)棉(mian)(mian)(mian)苗(miao)(miao)(miao)株高(gao)不足35厘米(mi)(mi)的移(yi)(yi)栽大田(tian)，只能使用(yong)對(dui)棉(mian)(mian)(mian)花(hua)安全的選(xuan)擇性除(chu)草(cao)(cao)(cao)(cao)(cao)劑(ji)(ji)除(chu)草(cao)(cao)(cao)(cao)(cao)。品(pin)種和用(yong)法：每667平(ping)方(fang)米(mi)(mi)用(yong)5%精禾(he)(he)草(cao)(cao)(cao)(cao)(cao)克(ke)(ke)乳油(you)(you)4o毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～60毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)、或(huo)10.8%高(gao)效蓋草(cao)(cao)(cao)(cao)(cao)能乳油(you)(you)20毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～30毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)、或(huo)15%精穩殺得乳油(you)(you)4o毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)枷毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)對(dui)水(shui)15公斤～30公斤噴(pen)(pen)霧。②棉(mian)(mian)(mian)花(hua)蕾期且(qie)株高(gao)在(zai)35厘米(mi)(mi)以上的移(yi)(yi)栽棉(mian)(mian)(mian)田(tian)除(chu)草(cao)(cao)(cao)(cao)(cao)技(ji)術：選(xuan)用(yong)草(cao)(cao)(cao)(cao)(cao)甘(gan)膦(lin)(lin)(lin)類(lei)滅生(sheng)性除(chu)草(cao)(cao)(cao)(cao)(cao)劑(ji)(ji)進(jin)行(xing)行(xing)間(jian)定(ding)向(xiang)噴(pen)(pen)霧除(chu)草(cao)(cao)(cao)(cao)(cao)，每667平(ping)方(fang)米(mi)(mi)用(yong)41%草(cao)(cao)(cao)(cao)(cao)甘(gan)膦(lin)(lin)(lin)水(shui)劑(ji)(ji)（農(nong)達(da)(da)、農(nong)旺等）loo毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～200毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)或(huo)10%草(cao)(cao)(cao)(cao)(cao)甘(gan)膦(lin)(lin)(lin)水(shui)劑(ji)(ji)450毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～800毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)。施藥(yao)(yao)時要在(zai)噴(pen)(pen)頭(tou)上加(jia)防(fang)護(hu)罩，壓低噴(pen)(pen)頭(tou)，避免藥(yao)(yao)液漂移(yi)(yi)到(dao)棉(mian)(mian)(mian)花(hua)葉(xie)片(pian)上產(chan)生(sheng)藥(yao)(yao)害(hai)(hai)。每667平(ping)方(fang)米(mi)(mi)用(yong)5%精禾(he)(he)草(cao)(cao)(cao)(cao)(cao)克(ke)(ke)乳油(you)(you)60毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～80毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)+90%禾(he)(he)耐斯乳油(you)(you)60毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)、或(huo)5%精禾(he)(he)草(cao)(cao)(cao)(cao)(cao)克(ke)(ke)乳油(you)(you)60毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～80毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)加(jia)10%乙(yi)羧氟草(cao)(cao)(cao)(cao)(cao)醚(mi)20毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)～30毫(hao)(hao)(hao)(hao)(hao)升(sheng)(sheng)對(dui)水(shui)30公斤噴(pen)(pen)霧。此時期行(xing)間(jian)定(ding)向(xiang)除(chu)草(cao)(cao)(cao)(cao)(cao)慎(shen)用(yong)百草(cao)(cao)(cao)(cao)(cao)枯類(lei)除(chu)草(cao)(cao)(cao)(cao)(cao)劑(ji)(ji)，否則(ze)棉(mian)(mian)(mian)苗(miao)(miao)(miao)容易產(chan)生(sheng)藥(yao)(yao)害(hai)(hai)。

三補是棉花大田花鈴期補施除草劑

對于田間(jian)零(ling)星(xing)的雜草(cao)，可(ke)以選用(yong)滅生性除(chu)草(cao)劑草(cao)甘(gan)膦(lin)類(lei)，采取點片結合(he)的方法(fa)補施(shi)除(chu)草(cao)劑，用(yong)法(fa)同蕾期施(shi)用(yong)方法(fa)，用(yong)量視面積大小而定。