1 walnut anthracnose
1.1 symptoms
Anthracnose is mainly harmful to the fruit, producing dark brown, slightly concave, round or irregular lesions. When the disease is heavy, the whole fruit rots and shrinks and shrinks. When the weather is wet, a pink dot with a wheel-like arrangement is formed on the lesion.
1.2 Prevention methods
1.2.1 Fitness cultivation
Planting disease-resistant varieties; clearing the garden in winter, removing diseased fruits, diseased leaves, growing seasons, removing diseased bodies in a timely manner, burning intensively; scientifically applying fertilizer water to enhance tree potential; strengthening summer pruning, improving ventilation and light transmission conditions in the garden, and controlling diseases happened.
1.2.2 Chemical control
At the beginning of the disease, you can use 75% chlorothalonil WP 500 times solution, 70% senseng zinc WP 600 times solution, 50% anthrax umme WP 600 times solution, spray, 7~10d once, even Spray 2~3 times.
2 walnut black spot
2.1 symptoms
Black spot disease damages walnut leaves, new shoots and fruits. The leaves are susceptible, the lesions on the young leaves are brown, polygonal; the lesions on the older leaves are round, the center is taupe, the edges are brown, sometimes there are yellow halos around, and the central taupe sometimes forms perforations. When the disease is heavy, the lesions are connected to each other. The lesions on the shoots are long, brown, and slightly sunken. When the disease is heavy, the lesions surround the branches, and the upper part of the branches die. The fruit is damaged, and the initial epidermis is a small and slightly bulging brown soft spot. At the later stage, it gradually expands and becomes dark and sag, and there is a water-soaked halo on the periphery. When the disease is heavy, the nuts become black and rot.
2.2 Prevention methods
2.2.1 Fitness cultivation
Clear the diseased leaves, diseased fruits, diseased shoots, etc. of the orchard, reduce the source of the bacteria; scientifically apply fertilizer water, enhance the tree potential, improve the tree resistance; timely control pests (especially walnut limbs), reduce wounds, and achieve disease prevention purposes .
2.2.2 Chemical control
Spraying 1:0.5～1:200 Bordeaux mixture in the leaves (before the emergence of female flowers), after flowering and early in the young fruit; in the early stage of the disease, spray 72% agricultural streptomycin soluble powder 4000 times solution, 65% mancozeb Zinc wettable powder 600 times liquid and the like.
3 walnut brown spot
3.1 symptoms
Brown spot disease is the damage to leaves, shoots and fruits. First, there are nearly round or irregular lesions on the leaves, with a taupe in the middle and a dark yellow-green or purple-brown edge. The lesions often fuse together to form a large dead zone of scorch, often with yellow or golden yellow around, which is easy to fall off early. On the onset of young shoots, there are dark brown lesions with long oval or irregular shape, and the edges are light brown. There are often longitudinal cracks in the middle of the lesions. The surface of the diseased part is scattered with black small particles. The lesions on the fruit are smaller than the leaves, sag, spread, and the fruit turns black and rots.
3.2 Prevention methods
3.2.1 Agricultural control
Strengthen the management of fertilizer and water, enhance the tree potential and improve disease resistance. Timely removal of the diseased branches of the orchard, deep burial or burning of the diseased leaves, elimination of the source of the bacteria, and prevention of the disease from continuing to invade and spread.
3.2.2 Chemical control
In addition to the spray of Bordeaux mixture and methyl thiophanate, the effect of 300 times of Alik's capsule water agent on walnut brown spot disease is better.
LED Lamp Bead light-emitting principle
The terminal voltage of the PN junction constitutes a certain potential barrier. When the forward bias voltage is applied, the potential barrier drops, and the majority carriers of the P region and the N region diffuse to each other. Since the electron mobility is much larger than the hole mobility, a large number of electrons will diffuse into the P region, which constitutes the injection of minority carriers into the P region. These electrons recombine with holes in the valence band, and the energy obtained during recombination is released in the form of light energy. This is the principle of PN junction light emission.
Features of LED Lamp Beads
1. Voltage, LED lamp beads use low-voltage Power Supply, and the power supply voltage is between 2 and 4V, which varies according to different products, so it is driven by a high-voltage power supply. Safer power supply, especially for public places.
2. Current, the working current is between 0 and 15 mA, and the brightness becomes brighter with the increase of the current.
3. Efficiency, energy consumption is reduced by 80% compared with incandescent lamps with the same luminous efficiency.
4. Applicability, very small, each unit LED chip is 3 to 5 mm square, so it can be prepared into various LED lamp bead shaped devices, and is suitable for variable environments.
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