铁比较集中分布在叶绿体中，铁虽然不是叶绿素的成分，但它对叶绿素的形成起酶促作用，因此，缺铁时造成植物“缺绿”或“黄化”。由于铁在植物中很难转移再利用，所以缺绿症首先出现在嫩叶上。铁是铁氧还蛋白的重要组成部分，铁氧还蛋白与叶绿体结合在光合作用中起传递电子的作用，因此，缺铁时光合作用受到影响;铁氧还蛋白还是豆科作物根瘤中豆血红素的成分(有固氮作用)，铁又是铁钼固氮酶的成分，因而缺铁时豆科作物氮素供应受到影响，植株生长受到一定限制。此外，铁是磷酸蔗糖酶.好的活化剂，缺铁时蔗糖的形成受影响;铁也是许多氧化酶的成分，对植物呼吸有促进作用，缺铁影响呼吸，使高能物质腺三磷(ATP)的形成减少。

Iron is mainly distributed in chloroplasts. Although iron is not a component of chlorophyll, it plays an enzymatic role in the formation of chlorophyll. Therefore, when iron deficiency occurs, plants will be "green deficient" or "yellow". Because iron is difficult to transfer and reuse in plants, chlorosis first occurs in young leaves. Iron is an important part of ferredoxin. The binding of ferredoxin and chloroplast plays the role of electron transfer in photosynthesis. Therefore, the cooperation of iron deficiency is affected. Ferredoxin is also the component of heme in legume root nodules (with nitrogen fixation effect), and iron is the component of iron molybdenum nitrogenase, so nitrogen supply of leguminous crops is affected when iron deficiency occurs Growth is limited. In addition, iron is the best activator of sucrase phosphate, and the formation of sucrose is affected by iron deficiency; iron is also a component of many oxidase, which can promote plant respiration, and reduce the formation of high-energy substance adenotriphosphate (ATP).

作物缺铁的共同症状是幼叶叶脉间失绿，严重时完全失绿成白色，称为“黄化病”。

The common symptom of iron deficiency in plants is chlorosis between veins of young leaves. In severe cases, chlorosis becomes white, which is called "xanthosis".

作物缺铁时可喷施0.75-1.0%的硫酸亚铁溶液，但由于亚铁容易氧化成高铁，很快就不能被作物吸收。而且在植物体中移动性小，并很少横向运输，所以喷施铁肥时，要喷在嫩叶上，并喷2次以上。实践证明，有机铁效果优于硫酸亚铁，螯合铁效果优于有机铁，EDDHA-Fe是螯合铁产品中的..产品。

Crop iron deficiency can be sprayed 0.75-1.0% of ferrous sulfate solution, but because ferrous is easy to oxidize to high iron, soon can not be absorbed by the crop.And in the plant body mobility is small, and rarely transverse transport, so when spraying iron fertilizer, to spray on the tender leaves, and spray more than 2 times.Practice has proved that the effect of organic iron is better than that of ferrous sulfate, the effect of chelated iron is better than that of organic iron, and EDDHA-Fe is the top product of chelated iron products.

在实际诊断中，根据外边症状判别作物缺铁时，由于铁、锰、锌三者容易混淆，需注意鉴别。缺铁和缺锰：缺铁褪绿程度通常较深，黄绿间色界常明显，一般不出现褐斑，而缺锰褪绿程度较浅，且常发生褐斑或褐色条纹。缺铁和缺锌：缺锌一般出现黄斑叶，而缺铁通常全叶黄白化而呈清晰网状花纹。

In the actual diagnosis, when judging crop iron deficiency according to external symptoms, because iron, manganese and zinc are easy to be confused, attention should be paid to differentiation.Iron deficiency and manganese deficiency: iron deficiency chlorosis degree is usually deep, yellow-green interchromatic border is often obvious, generally do not appear brown spots, and manganese deficiency chlorosis degree is shallow, and often occur brown spots or brown stripes.Lack of iron and zinc: lack of zinc generally appear macular leaves, and lack of iron usually whole leaves yellow and white and show clear mesh pattern.