要(yao)(yao)及時追肥大白菜以(yi)葉(xie)為產品,對氮磷鉀的要(yao)(yao)求很(hen)敏感,生(sheng)(sheng)產中不(bu)但(dan)要(yao)(yao)施(shi)好基肥,還要(yao)(yao)根據不(bu)同生(sheng)(sheng)長期(qi)進行追肥。生(sheng)(sheng)長期(qi)追肥多以(yi)速效氮肥為主,如硫(liu)酸(suan)銨(an)、碳酸(suan)氫銨(an)、磷銨(an)、尿素等(deng)。追肥時期(qi)要(yao)(yao)掌握好,一般在(zai)苗期(qi)、蓮(lian)座期(qi)、結(jie)球(qiu)始期(qi)和結(jie)球(qiu)中期(qi)分4次追施(shi)。苗期(qi)每(mei)畝(mu)追施(shi)硫(liu)酸(suan)銨(an)5~10公(gong)(gong)(gong)斤(jin)(jin),蓮(lian)座期(qi)每(mei)畝(mu)施(shi)腐熟(shu)農家肥1000~1250公(gong)(gong)(gong)斤(jin)(jin)、碳酸(suan)氫銨(an)15公(gong)(gong)(gong)斤(jin)(jin)或硫(liu)酸(suan)銨(an)10公(gong)(gong)(gong)斤(jin)(jin),結(jie)球(qiu)始期(qi)每(mei)畝(mu)追施(shi)碳酸(suan)氫銨(an)25公(gong)(gong)(gong)斤(jin)(jin)或硫(liu)酸(suan)銨(an)15~20公(gong)(gong)(gong)斤(jin)(jin),結(jie)球(qiu)中期(qi)每(mei)畝(mu)追施(shi)稀(xi)糞(fen)液(ye)(ye)1000~1250公(gong)(gong)(gong)斤(jin)(jin)、碳酸(suan)銨(an)10~15公(gong)(gong)(gong)斤(jin)(jin)或1%的尿素溶液(ye)(ye)。
病蟲要(yao)兼(jian)治(zhi)菜(cai)(cai)農對大白(bai)(bai)菜(cai)(cai)三大病害(hai)的(de)防(fang)治(zhi)很重視,但往(wang)往(wang)忽(hu)視蟲害(hai)的(de)防(fang)治(zhi)。其實(shi)很多病害(hai)發(fa)生蔓延與害(hai)蟲有著密不可(ke)分的(de)關系(xi)。蚜蟲是(shi)傳播病毒(du)病的(de)罪(zui)魁禍首,可(ke)使大白(bai)(bai)菜(cai)(cai)萎縮死亡;軟腐病菌(jun)主要(yao)通過昆蟲、雨水(shui)和灌溉水(shui)傳染(ran),從傷口(kou)浸(jin)染(ran)大白(bai)(bai)菜(cai)(cai)。害(hai)蟲為(wei)害(hai)后造成傷口(kou),有利(li)于病菌(jun)侵入致病。防(fang)治(zhi)好菜(cai)(cai)青蟲、黃曲條跳甲及地(di)下(xia)害(hai)蟲,減少(shao)蟲害(hai)傷口(kou),能有效地(di)減輕(qing)大白(bai)(bai)菜(cai)(cai)軟腐病的(de)發(fa)生。所以防(fang)治(zhi)害(hai)蟲也是(shi)防(fang)治(zhi)病害(hai)的(de)重要(yao)措(cuo)施。
捆綁(bang)(bang)要推(tui)遲捆綁(bang)(bang)可(ke)以防止大(da)白菜遭受霜凍(dong),促進壯心,還便于收(shou)獲(huo)。但是捆綁(bang)(bang)不(bu)能(neng)過早,因為捆綁(bang)(bang)過早,外葉(xie)光合效能(neng)大(da)大(da)降低(di),妨(fang)礙大(da)白菜的正(zheng)常生(sheng)長(chang),不(bu)利于葉(xie)球的充實(shi)。一般在收(shou)獲(huo)前10~15天,停止澆水,將蓮座葉(xie)扶起,抱住葉(xie)球,然后用浸(jin)透的甘薯秧或谷草在離球頂3~5厘米處將葉(xie)捆住,使包心更堅實(shi)并繼續生(sheng)長(chang)。













