danshigouchengdanbaizhidechengfen,shishengchandejichu,yeshichanliangxingchengdewuzhijichu。guoshutineidanhanliangdi,suirannengchenghua,danshizuoguolvdi,guogexiao,guoshisedanzhicha,chanliangdi,changqiquedanhuidaozhiguoshukangnixingjianruo、壽命縮短;果樹體內氮含量高,雖然果個大,但枝葉徒長,花芽分化不良,落花落果嚴重,若夏秋季果樹葉片中氮含量超過2.5%,則果實推遲成熟,著色差,肉質粗,含糖量和硬度降低,不耐貯藏,生理病害多,不宜安全越冬。
雨季要供氮。6~7yuechuyuyujidediqu,youqishibaofeilijiaochadeguoyuan,danfeisuijiangyulinshiyanzhong,yizaochengquedan,shigongnengyezaoshuaihuozaoluo,suoyiyingbaozhengyujidanfeigongyingbuduanxian。
春季施氮肥,對當年開花、坐果無效。氮一般以硝態氮和銨態氮兩種形式為有效狀態,銨態氮、硝xiao態tai氮dan進jin入ru果guo樹shu體ti內nei後hou,轉zhuan化hua成cheng二er氧yang化hua氮dan,與yu碳tan水shui化hua合he物wu結jie合he生sheng成cheng氨an基ji酸suan,貯zhu存cun於yu樹shu體ti內nei。這zhe一yi轉zhuan化hua過guo程cheng的de時shi間jian雖sui然ran尚shang不bu明ming確que,但dan肯ken定ding是shi需xu要yao較jiao長chang時shi間jian的de。果guo樹shu開kai花hua、坐果需要的是樹體內已經貯存的氨基酸形式的氮。因此果樹補氮應在秋季施足基肥(8月下旬至9月上旬,有機肥為主,配合磷鉀肥)的基礎上於采收後追施氮肥或葉麵噴施1~2次高濃度氮肥(以不發生肥害為原則),而不應該春季補氮。
手機版




