Trace elements are necessary for plant growth. Although the demand for trace elements is not much during the normal growth of crops, some crops contain only a few millionths of the total trace elements. The effect is huge. When the necessary nutrient elements of the crop are balanced, the crop grows lushly. When the crop lacks one or more elements, the plant growth is affected, the morbidity appears, and it is even related to human health problems. It can be seen that trace elements have played a vital role in improving the quality of crops.
Trace elements required during crop growth：
Physiological functions: Many enzyme activators can promote the absorption of phosphorus and silicon by crops and improve the disease resistance of crops.
Deficiency: Causes the chlorophyll content of the leaves to decrease, and the intensity and rate of photosynthesis to decrease.
Physiological functions: Necessary for chlorophyll synthesis; participating in redox reactions and electron transfer in the body; participating in nucleic acid and protein metabolism, and also related to the synthesis of carbohydrates, organic acids and vitamins.
Deficiency: apical or young leaves lose green and yellowing, from inter-vein green to whole yellowish white, fruit trees "yellow leaf disease", flowers and vegetables Chlorotic stripes
Physiological function: promote meristem growth and nucleic acid metabolism; promote carbohydrate transport and metabolism; participate in phenol metabolism and lignin formation; related to the establishment and development of reproductive organ
Deficiency: Stem apex, root apex growth stoppage, or shrinkage die, rapeseed "flower but not fruit", wheat "spike but not fruit", cauliflower "brown heart disease", radish "black heart disease", etc.
Physiological functions: participate in photosynthesis; enzyme components and regulate enzyme activity; regulate redox processes in plants.
Deficiency: Green leaf yellowing between young leaf veins, small brown spots scattered throughout the leaves, oat "grey spot disease", beans "brown spot disease", beet "macular spot disease"
Physiological functions: components of enzymes; participate in photosynthesis; participate in nitrogen metabolism; affect flower organ development.
Deficiency: thin growth, new leaves lose green and yellow, leaf tips: white and curly, leaf edges grayish yellow, and necrotic spots appear on the leaves; apex of gramineous grass is white withered, development of reproductive organs is hindered, not strong or only pupae; Fruit trees "stag disease" or "branch blight."
Physiological functions: Participate in photosynthesis as a component of carbonic anhydrase; Participate in metabolism as a component of multiple enzymes: Participate in the synthesis of auxin: Promote the development of reproductive organs.
Deficiency: short plants, short internodes, delayed fertility; small leaves, clusters; chlorosis between middle and lower leaves. Rice "dwarf disease", corn "white seedling disease", citrus leaf disease "," cluster leaf disease "and so on.
Physiological functions: Participate in nitrogen metabolism as a component of nitrate reductase and nitrogenase; promote the synthesis of vitamin C; have a close relationship with phosphorus metabolism; enhance disease resistance.
Deficiency: The leaves are malformed, elongated, twisted and twisted, and the growth is irregular; the old leaves are pale green and yellow with brown spots and thickened and scorched, such as cauliflower and tobacco "whip-tailed leaves" and legume hawthorn "cup-shaped "Leaf" and nodules
Nickel is good for germination and seedling growth. The nickel content in plants is generally between 0.05-5.0g / kg. Low concentration of nickel can promote the activities of peroxidase and ascorbate oxidase in alfalfa leaves, and promote the degradation of toxins secreted by harmful microorganisms, thereby enhancing the disease resistance of crops. Excessive nickel is also toxic to plants, with varying symptoms, delayed growth, chlorosis and deformation of leaves; spots, stripes, small fruit, early coloration, etc.
In short, different plants lack different nutrient elements and behave differently.
The root of crop deficiencies is in the soil. In addition to the long-term partial application of NPK and the lack of timely supplementation of trace elements, the deterioration of soil physical properties is another major cause of trace loss.