Chinese medicine practitioners pay attention to "looking", "smelling", "questioning" and "cutting". Although plants can't talk, the same reason, for plants to see a doctor, we must follow four steps, that is, "looking" and "looking". "Q" and "Broken". Today, lime nitrogen manufacturers first tell you about the "expectation" of the diagnosis technology of vegetable pests and diseases.
It is from a distance, and it is judged whether it is a film or a film.
(1) into pieces
1. Organic fertilizer: Organic manure causes the concentration of soil solution to be too high in the process of decomposing fermentation, and releases a large amount of heat, causing root burning, dead seedlings, leaf deformity, and vegetables are gradually wilting and dead.
2. Inorganic fertilizer: Excessive application of chemical fertilizer results in high concentration of soil solution, and the water potential in the soil is reduced, which causes the water in the root system to flow back into the soil, that is, the root system is difficult to absorb water, and then the fertilizer is harmful, which is commonly called “burning seedling”.
3, roots: due to low soil temperature, high humidity and other factors lead to roots do not send new roots or adventitious roots, root bark rust after rotting, causing the upper part of the wilting, and easy to pull up, the upper part of the leaf edge is scorched; The film is dry and seems to be deficient.
4. Water shortage: Due to the low water content in the soil or the transpiration of high temperature, the vegetables are temporarily short of water and wilting. If the water is replenished in time, it can return to normal.
5, high temperature barrier: the sunburn on the fruit, the skin of the initial victim fruit is grayish white leather, the surface is thin, shrinking, cell tissue necrosis, hard, as if boiled by boiling water;
The flower buds are poorly differentiated, the number of female flowers is significantly less, the flowering nodes are increased, and some even have no female flowers directly;
Many malformations, zucchini, cucumber, etc. are prone to problems such as long, tip, big head and other deformed melons or poor color, reducing or losing the value of the commodity.
6, low temperature barrier: plants suffer from cold or cold damage, causing contiguous symptoms. The top bud is frozen, the growth point is harmed, the top bud is frozen and the growth stops. The leaves are frozen, the edges are rolled up, the chlorosis is lost, and even yellow or white, and dry,
The petiole and stem parts often appear purple-red in the early stage of freezing damage, and become black and dead in severe cases; when the fruit is frozen, uneven coloring, deformed fruit and heart-breaking fruit usually appear, and the cane-fruit vegetables will also have stiff fruit;
The roots are frozen, growth stops, and gradually turns yellow or even dies, hindering the normal absorption of nutrients and water, resulting in nutrient deficiencies.
7. Greenhouse gas: Symptoms such as wilting, discoloration, necrosis caused by acid gases (sulphur dioxide, nitrogen dioxide, carbon monoxide, etc.) or alkaline gases (gas such as ammonia) are usually caused by improper fertilization.
The detection of harmful gases in greenhouses and greenhouses is generally judged by the detection of dew drops in the greenhouse. The detection of the pH of the dew drops is usually carried out before the morning ventilation. The detection method can be carried out by using a precision pH test paper to determine the type of gas and the degree of damage according to the detection result of the dew drop pH. If the pH is below 4.6, acid gases such as sulfur dioxide and carbon dioxide are seriously exceeded.
8, phytotoxicity: general phytotoxicity is acute and chronic. Acute phytotoxicity occurs from a few hours to 3-4 days after spraying, such as burns, wilting, defoliation, falling flowers, falling fruits, spots on young tissues, such as brown spots, yellow spots, net spots, etc. common.
Chronic phytotoxicity is caused by obvious symptoms after spraying for a long time, such as poor growth of branches and leaves, yellowing of leaves, deformity of stems, leaves, fruits and roots, such as curling leaves, clumps, swollen roots, etc. It is accompanied by spots, delayed maturity, and deteriorated flavor. Lime nitrogen manufacturer
9. Lack or excess of elements: deficiency or overdose caused by lack or excess of certain elements. If the nitrogen is deficient, the leaves become pale green or yellow, and gradually dry or the old leaves fall off;
In the absence of phosphorus, the stems and leaves become thinner, the growth is slow, the leaves become dull dark green leaflets, the petioles are purple, the roots are poorly developed, the plants are short, and the fruit ripening period is postponed; when the magnesium is deficient, the old leaves first appear as green deficiency symptoms, gradually Involving young leaves, the mesophyll is chlorotic and the veins remain green, and in severe cases, the leaves are withered;
When the sulfur deficiency occurs, the leaf veins are pale green, but the tissue is not aging, and the stem is obstructed. Generally, it starts from the young part and is similar to nitrogen deficiency. When the iron is lacking, the veins of the young leaves are chlorotic, yellowish white. The leaves turn yellowish white and dry;
In the absence of boron, the growth points of the main stem and the lateral branches are atrophied, browned, and dry, and the plant type is cluster-like. The leaf body and petiole are curved, resulting in a "leaf burning" condition, the root growth is blocked, and the root becomes brown and spoiled when boron is severely deficient; In the absence of manganese, the young leaves and the old leaves appear to be deficient in green, or brown spots and leaves are produced, and the upper part of the stem becomes brown and dead;
In the absence of copper, the growth is weak, the leaves are chlorotic, and the tip of the leaves becomes white; when the zinc is deficient, the color of the leaves turns yellow or bronze, and there are spots; when the molybdenum is absent, the leguminous vegetables cannot form nodules, and the broccoli cannot form a flower ball.
10. Blight: A type of disease caused by some species of Phytophthora fungi that can damage leaves, stems, vines, fruits and roots, mainly causing rapid necrosis and decay of vegetable flowers, fruits and leaf tissues. It is very popular and has serious devastating diseases.
Due to the rapid onset of the disease, if a large area of symptoms occurs in a short period of time, the disease can be considered.
(2) The occurrence of the "looking" of lime nitrogen manufacturers
1. Fusarium wilt: This kind of disease is a disease caused by heavy earthworms for many years. It invades the vascular bundle from the roots and blocks the transportation of nutrients and water after the vascular bundle is over. The early noon wilting recovers sooner or later. Most occur in the fruit expansion period after fruit setting, and often die overnight after watering.
2, root rot: early plants do not show symptoms, followed by the degree of root rot, the function of absorbing water and nutrients is gradually weakened, the upper part of the ground due to nutrient supply is in short supply, when the light is strong before and after noon, the evaporation is large, the upper leaves of the plant It is only wilting, but it can be restored at night. When the condition is severe, the root bark becomes brown and separates from the pith, and finally the whole plant dies.
3, stem-based rot: only damage the base of the stem, most of the soil surface 3-5 cm above and below the water surface stained dark spots, and quickly spread to the surrounding, hand pinch soft, the leaves turn yellow from bottom to top, after Wilted.
4, Sclerotinia sclerotiorum: more from the fork part of the disease, grayish white, slightly sunken, phloem rot, and its mycelium can invade the diseased stem, the late epidermis longitudinal crack, lesion size, shape, length, edge water In the stains, the surface and the diseased stems are covered with white cotton-like hyphae and black sclerotia, and the diseased part is swollen and dead.
5, the disease is dry: the disease caused by Pythium and Phytophthora fungi is generally called squatting disease, which shows that the stem base of the seedlings is soft and watery, rapidly wilting, and finally the base of the stem is linear Contracture, sometimes the cotyledons have not yet manifested symptoms and have fallen;
The seedling disease caused by Rhizoctonia is generally called the blight, which is characterized by brown spots on the base of the affected seedlings, which gradually shrink the young stems until the seedlings die, and generally do not fall immediately.
6. Bacterial wilt disease: cut the stem of the diseased plant, squeeze the vascular bundle by hand, and there is white pus overflow in the cross section. In severe cases, the stem of the ground rots, and white pus is seen around, and there is a foul smell. The catheter is generally not discolored, and the roots are not rotted.
7. Nematode disease: Invasion of fibrous roots and lateral roots by nematodes, the diseased part is swollen into irregular shape-like knots, and the root knots are milky white worms. The root knots are of different sizes, a string of sugar-like rugs, and the infected plants are thin and small. , poor growth, the results are small and small.
8. Underground pests are caused by underground pests such as cockroaches, crickets and ground tigers.