钙以果胶酸钙与其他物质一起构成细胞壁，细胞分裂也要有钙的存在，因此，缺钙会防碍新细胞的形成，细胞壁受到破坏，根尖细胞受到明显破坏；钙对氮的代谢也有一定的作用，根据试验表明，钙离子，对蛋白质和酰胺的合成有促进作用；豆类作物根瘤的形成和固氮作用都要求有较高的浓度的钙营养，如钙不足则影响生物固氮过程，所以在酸性土壤上种花生、大豆等豆类作物时，施用石灰会获得良好的效果；钙还是某些酶的活化剂；钙还有调节植物体内pH值的功用，钙与钾同时存在，对维持细胞生理平衡和原生物质胶体的正常状态，有着重要作用；钙离子下多种离子有拮抗作用，因此，有钙存在可避免或减少铵、氢、铝、钠离子过多的毒害。此外，钙与真菌病害有一定的关系，据研究，钙含量与真菌病害的感染呈负相关，即钙多病轻，钾多钙少时感病重，如番茄青枯病的发生与茎中钙含量呈负相关。

Calcium forms cell wall with calcium pectate and other substances, and cell division also needs calcium. Therefore, calcium deficiency will hinder the formation of new cells, destroy cell wall and root tip cells; calcium also plays a certain role in nitrogen metabolism. According to experiments, calcium ion can promote the synthesis of protein and amide; the formation and development of legume root nodules High concentration of calcium is required for nitrogen fixation. If calcium is insufficient, it will affect the process of biological nitrogen fixation. Therefore, when planting peanuts, soybeans and other legumes on acidic soil, lime can obtain good results; calcium is also an activator of some enzymes; calcium also has the function of regulating the pH value in plants. Calcium and potassium exist at the same time, which can maintain the physiological balance of cells and the colloid of biomass The results show that the presence of calcium can avoid or reduce the toxicity of ammonium, hydrogen, aluminum and sodium ions. In addition, there is a certain relationship between calcium and fungal diseases. According to research, calcium content is negatively correlated with fungal disease infection, that is, calcium is more disease light, potassium is more and calcium is less, the disease is more serious. For example, the occurrence of tomato bacterial wilt is negatively correlated with the calcium content in the stem.

作物主要吸收钙离子，豆类作物和蔬菜及某些果树需钙较多，禾谷类作物需钙较少。钙在植物体中移动性小，主要集中在较老的组织中，很少向幼嫩器官运送，因此，作物缺钙症状首先在根尖，..，顶芽或心叶发生。缺钙的症状是植株矮小，未老先衰，幼叶卷曲而脆弱，叶中有坏死组织，根尖和生长细胞逐渐腐烂死亡；许多作物的果实顶部腐烂，如西瓜、番茄、马铃薯的顶部变褐腐烂。

Crops mainly absorb calcium ions. Legumes, vegetables and some fruit trees need more calcium than cereal crops. Calcium is less mobile in plants, mainly concentrated in older tissues, and rarely transported to young organs. Therefore, the symptoms of calcium deficiency first occur in root tip, apex, terminal bud or heart leaf. The symptoms of calcium deficiency are that the plants are short, the young leaves are curly and fragile, there are necrotic tissues in the leaves, the root tips and growth cells gradually decay and die on many crops such as watermelon, tomato and potato..

作物缺钙可施石灰或其他钙肥料改善钙营养，但效果.快.好的是喷0.3-0.5%的螯合钙溶液。

Calcium deficiency can be improved by applying lime or other calcium fertilizers, but the fastest and best effect is spray 0.3-0.5% chelate calcium solution.