Leaf of the middle or middle third of the new spur on the tree periphery, with or without fruit, between January 15th and the end of February (south hemisphere).
Boron is an essential micronutrient to plants and is involved in functions such as meristematic growth and cellular differentiation, maturation, division and elongation. Many species vary in their requirements for boron and, usually, there is a narrow range between adequate and toxic levels of boron.硼是植物必需的微量营养素，参与分生组织生长和细胞分化、成熟、分裂和伸长等功能。许多物种对硼的需求量各不相同，通常，硼的充足水平和毒性水平之间的范围很窄。
摘要：硼是一种重要的植物微量营养元素，主要以硼酸的形式通过根系吸收。其在植物代谢中的重要作用涉及具有顺式二醇基团分子的稳定。该元素涉及细胞壁和膜的结构和功能；因此，它参与许多离子、代谢物和激素转运反应。硼在缺乏和毒性之间的范围极窄，硼供应不足会对农业植物的产量产生不利影响。缺硼问题可以通过施肥来解决，而土壤硼毒性可以通过各种方式来改善；然而，这些方法成本高、耗时长，而且往往会产生暂时的效果。植物物种以及物种内的基因型在硼需求方面存在显著差异；因此，土壤可利用的硼对一种作物缺乏，可能会对另一种作物产生毒性影响。关于硼利用效率和毒性耐受性的广泛记录的种内遗传变异性，加上硼的生理学和遗传学知识，应引导开发高效和耐受的品种，这可能是硼供应不足或过量问题的长期可持续解决方案。
Abstract: Boron is an essential plant micronutrient taken up via the roots mostly in the form of boric acid. Its important role in plant metabolism involves the stabilization of molecules with cis-diol groups. The element is involved in the cell wall and membrane structure and functioning; therefore, it participates in numerous ion, metabolite, and hormone transport reactions. Boron has an extremely narrow range between deficiency and toxicity, and inadequate boron supply exhibits a detrimental effect on the yield of agricultural plants. The deficiency problem can be solved by fertilization, whereas soil boron toxicity can be ameliorated using various procedures; however, these approaches are costly and time-consuming, and they often show temporary effects. Plant species, as well as the genotypes within the species, dramatically differ in terms of boron requirements; thus, the available soil boron which is deficient for one crop may exhibit toxic effects on another. The widely documented intraspecies genetic variability regarding boron utilization efficiency and toxicity tolerance, together with the knowledge of the physiology and genetics of boron, should result in the development of efficient and tolerant varieties that may represent a long-term sustainable solution for the problem of inadequate or excess boron supply.
虽然硼是一种必需的植物营养元素，但过量会产生毒性。由于井水中的过量硼不存在补救措施，因此应在景观中种植耐硼植物。“不幸的是，你无法对井水采取任何措施来降低其硼含量，因此选择耐硼植物是明智的选择。”
Although boron is an essential plant nutrient, excessive amounts can become toxic. Since no remedies exist for excess boron in well water, stick to boron-tolerant plants in the landscape.“Unfortunately, there is nothing you can do to your well water to reduce its level of boron, so selecting boron-tolerant plants is a wise direction to take.”
硼（B）的毒性最初出现在较低、较老的叶子上。硼中毒的早期症状表现为下部叶片起皱和叶缘脉间失绿。起皱最有可能是由于当B的毒性水平存在时，细胞缺乏膨压引起的。这种褶皱会在叶片表面形成，导致叶片变形。随着时间的推移，脉间褪绿将向内移动，并在大部分叶片上发展。当供应过量的B时，细胞会迅速死亡，导致坏死斑点。随着症状的发展，褪绿和坏死会在植株上发展到其他叶片。
镁是一种营养元素，能够在植物新旧叶片之间移动的矿物质。植物缺镁会迅速发展，导致下部叶片的镁流失。镁是最重要的生长元素之一，因为它位于组织内叶绿素分子的中心。这意味着，如果缺镁，叶绿素缺乏会导致植物生长发育不良。
镁是一种高移动的元素，对植物生长发育至关重要。它在土壤中的存在取决于几个因素：岩石材质、气象学程度、当地气候以及特定的耕作制度和做法，如作物类型、耕作强度和作物轮作以及施用方法。因此，镁的含量可能因土壤类型的不同而有很大差异。在热带和砂质土壤中，预计镁含量较低，而沼泽、泥炭沼泽、盐渍土附近的土壤，以及通常粘土含量较高的土壤，镁含量较高。
镁对我们植物的健康起着重要作用。它是我们的植物如何将光源转化为能量，促进植物生长和茁壮成长的关键成份之一。
