Identification of vegetable deficiency symptoms and remedial measures

First, nitrogen deficiency: When the vegetable seedlings lack nitrogen deficiency, the seedlings grow weak, the stems are short and fine, the leaves are small, the two cotyledons first turn yellow, and continue to develop upwards. Finally, the whole plant is yellow or brown, and when it is severe, it will die; root vegetables Not inflated; knots are not easy to ball or bad balls. Remedial measures: Urea urea 7.5 to 10 kilograms, or use human urine plus appropriate amount of urea water pouring, can also spray 0.5-1% urea solution. 2. Phosphorus deficiency: Plants are short, leaves are small, leaf color is dark green, and the lower leaves become purple or red-brown; poor growth of lateral roots, roots of root vegetables do not swell; fruit vegetables delayed results or fruit ripening period is delayed. Remedy: Use 0.5 kg of superphosphate per mu for water soaking for 24 hours, add 50 kg of water after filtration, and apply 0.5 kg of urea to spray foliar, spray twice. Or use 100-150 grams of potassium dihydrogen phosphate and 50 kg of water for spraying. Third, the lack of potassium: seedlings in the seedling stage potassium deficiency symptoms are not obvious. In the adult seedling stage, symptoms appear on the old leaves. The tips and leaves of the old leaves turn yellow or turn brown, and spots of tissue necrosis along the veins are observed. The plants are poor in cold resistance and drought resistance, and are easy to fall down. Symptoms appear in the early stages of growth of the leafy vegetables; symptoms occur when the root vegetables are inflated; symptoms occur when the knots begin at the beginning of the knot, and the leaves shrink and have a hard touch; fruits and vegetables do not grow during the early stages of growth. Deficiency of performance, when the fruit is enlarged, symptoms appear on the old leaves. Remedy: Topdressing potassium chloride 5-8 kg per acre or plant ash 75-100 kg can also be foliar spray 1% potassium chloride solution or 3-5% ash soak the filtrate.

Polysaccharides are polymeric carbohydrate molecules composed of long chains of monosaccharide units bound together by glycosidic linkages, and on hydrolysis give the constituent monosaccharides or oligosaccharides. They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch and glycogen, and structural polysaccharides such as cellulose and chitin.

Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure, these macromolecules can have distinct properties from their monosaccharide building blocks. They may be amorphous or even insoluble in water. When all the monosaccharides in a polysaccharide are the same type, the polysaccharide is called a homopolysaccharide or homoglycan, but when more than one type of monosaccharide is present they are called heteropolysaccharides or heteroglycans.

Natural saccharides are generally of simple carbohydrates called monosaccharides with general formula (CH2O)n where n is three or more. Examples of monosaccharides are glucose, fructose, and glyceraldehyde. Polysaccharides, meanwhile, have a general formula of Cx(H2O)y where x is usually a large number between 200 and 2500. When the repeating units in the polymer backbone are six-carbon monosaccharides, as is often the case, the general formula simplifies to (C6H10O5)n, where typically 40≤n≤3000.

As a rule of thumb, polysaccharides contain more than ten monosaccharide units, whereas oligosaccharides contain three to ten monosaccharide units; but the precise cutoff varies somewhat according to convention. Polysaccharides are an important class of biological polymers. Their function in living organisms is usually either structure- or storage-related. Starch (a polymer of glucose) is used as a storage polysaccharide in plants, being found in the form of both amylose and the branched amylopectin. In animals, the structurally similar glucose polymer is the more densely branched glycogen, sometimes called "animal starch". Glycogen's properties allow it to be metabolized more quickly, which suits the active lives of moving animals.

Cellulose and chitin are examples of structural polysaccharides. Cellulose is used in the cell walls of plants and other organisms, and is said to be the most abundant organic molecule on Earth.It has many uses such as a significant role in the paper and textile industries, and is used as a feedstock for the production of rayon (via the viscose process), cellulose acetate, celluloid, and nitrocellulose. Chitin has a similar structure, but has nitrogen-containing side branches, increasing its strength. It is found in arthropod exoskeletons and in the cell walls of some fungi. It also has multiple uses, including surgical threads. Polysaccharides also include callose or laminarin, chrysolaminarin, xylan, arabinoxylan, mannan, fucoidan and galactomannan.

Polysaccharide Series

Polysaccharide Series,Cordyceps Polysaccharide,Hericium Erinaceus Polysaccharide,Goji Polysaccharide

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