花生缺铁时,首先表现为上部嫩叶失绿,而下部老叶及叶脉仍保持绿色;严重缺铁时,叶脉失绿进而黄化,上部新叶全部变白,出现褐斑坏死,干枯脱落。
与花生缺氮、缺锌引起的失绿症比较,花生缺铁失绿症的特点突出表现在叶片大小无明显改变,失绿黄化显著。而缺氮引起的黄化失绿常使叶片变薄变小,植株矮小;缺锌易引起叶片大簇生,出现黄白小叶症。要准确的鉴定花生植株是否为缺铁黄化症,可用0.1%的硫酸亚铁溶液涂于叶片背面失绿处,如果5~8天后转绿,即可确认为缺铁。
防治花生缺铁黄化症,目前最常用的是叶面喷施铁索。一般可用0.1%~0.2%的硫酸亚铁(俗称黑矾、绿矾)溶液叶面喷施,每隔5~7天喷施1次,连喷3~4次。由于花生叶片比较光滑,离水性强,所以在喷施硫酸亚铁溶液时,可加入0.1%的中性洗衣粉,以增强其附着力,提高喷施效果。另外,目前市场上有一种叫做“黄叶灵”的产品,其主要成分为有机整合铁,其喷施效果明显的优于硫酸亚铁,可选择使用。
追问![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/0df3d7ca7bcb0a4631aac2ef6f63f6246a60af58?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/0df3d7ca7bcb0a4631aac2ef6f63f6246a60af58?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/8694a4c27d1ed21b5cac6633a96eddc450da3ffa?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
叶子发黄了以后,就成了这个样子,根部也开始腐烂。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b219ebc4b74543a9fb874e1a1a178a82b8011443?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/738b4710b912c8fc80ce411bf8039245d6882122?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追答有虫子、用药灌根
追问这个是什么病?什么虫子?要用什么药?