The latest course of disease and pest control techniques and methods of white orchids

White orchid plant shape erect branched, generous, native to Java, Indonesia, is now widely planted in Southeast Asia, in China's Fujian, Guangdong, Guangxi, Yunnan and other provinces and regions, many potted plants in the Yangtze River valley, but also can be used as spices and medicinal uses. Let's take a look at the pest control techniques of white orchids in the planting process.

Red wax scale

[hazard characteristics] the nymphs and adults of the red wax scale suck the flower juice, and their excrement often induces the occurrence of coal fouling disease, so that a layer of black mold or thick black film is formed on the leaves, the whole plant becomes a black tree, and the plant is weak, rarely blooming or unable to bloom at all.

[control methods] ① winter and early spring, combined with pruning to remove part of the multi-insect branches. ② can be scraped artificially in winter and spring if there are few or shorter flowers and plants. During the peak incubation period of nymphs, ③ sprayed 1000 times of 25% imidophos EC or 1500 times of 40% omethoate EC, once every 4-6 days, three times in a row. When ④ introduces flower seedlings, strict quarantine should be carried out to prevent insects from being brought into the plant.

Red spider

[hazard characteristics] Red spiders pierce the leaves with mouthparts to suck the juice, so that the chlorophyll is destroyed, the leaves show gray-yellow spots or patches, and the leaves are orange, shedding, or even shedding.

[control method] ① was soaked in citrus peel with 10 times water for one day and night, and the plants were sprayed after filtration. ② detergent 15g, 20% caustic soda 15ml, water 7.5kg, mix the three and spray the plant. ③ 50g plant ash, add 2.5kg water fully stir, soak for two days and night filter, add 3 grams of washing powder to mix and spray, once a day, spray 3 times, spray 3 times every week, can eliminate the second generation pests, put into the soil can control maggots. ④ lit a plate of mosquito-repellent incense, placed it in a pot of diseased plants, and then tied it tightly with a plastic bag. After an hour of smoking, it could kill eggs and adults.

Fried cicada

[hazard characteristics] the nymphs of fried cicadas suck the root juice of flowers in the soil, the adults suck the juice of the main leaves, and the female inserts the ovipositor on the branches to lay eggs, causing the branches to die.

[control method] ① killed the newly unearthed mature nymph in time. If the occurrence of ② is serious, it can light a fire near the tree trunk on a hot summer night, shake the branches, burn the cicadas and kill the cicadas that fall outside the fire. ③ uses sticky tung oil or a sticky ball kneaded by cobwebs to stick to the end of the bamboo pole to catch adults. ④ inspected and cut off the spawning branches in time from April to August.

Blown cotton scale

[hazard characteristics] the scale often does harm to the leaves, buds and shoots. When it is serious, the leaves turn yellow, causing the fallen leaves and shoots to wither, resulting in the death of the whole branch and the whole plant, even if some branches remain. It is also gray and black because of coal fouling caused by its excreta, which seriously affects the ornamental value.

[prevention and treatment methods] artificial prevention and treatment of ①: pinch off female worms and oocysts with hands or tweezers, or cut off branches and leaves of multiple worms. ② biological control: introduce natural enemies such as red ladybug and Australian ladybug to prey on cotton scale. ③ drug control: during the transfer period of newly hatched nymphs, 40% omethoate 1000 times, or 50% fenitrothion 1000 times, or ordinary washing powder 1000 times, once every 2 weeks, 3-4 times in succession.

Anthrax

[symptoms] dark brown round or subround spots appeared on the leaves, and the edges were slightly deep. after expansion, the center gradually became gray-white, with a size of 2-8 mm, and small black spots appeared on the lesions in the later stage, that is, the conidium disk of the pathogen. When the humidity is high, the disease spot is overflowing with orange slime, that is, the conidia of the bacteria. The disease is serious in rainy and wet weather.

[methods of prevention and treatment] at the initial stage of the disease, spray 100 times Bordeaux solution or 25% carbon tetralin 500 times solution or 70% anthrax Fumei 600 times solution.

Chlorosis

[symptoms] first of all, the young leaves on the tender shoots showed chlorosis, and then from top to bottom, from the leaf margin to the leaf base, the leaf margin gradually expanded to the mesophyll tissue, making the interveinal tissue chlorotic, and the veins continued to develop so that the leaves became milky yellow to milky white. In serious cases, the leaf margin is scorched, and even the whole leaf dries up and falls off. If the disease of 1-year-old seedlings occurs, its height is shorter than that of normal plants, while the disease of 3-4-year-old young trees is all yellowed, about 30 cm shorter than general health. Chlorosis leads to slow plant growth, shortening of internodes and shoot withering.

[prevention and treatment] ① was embedded with mung bean-sized ferrous sulfate under the basal cortex of the seedling, and then bandaged with plastic film to facilitate wound healing. ② trench with ferrous sulfate, and add rotten cake fertilizer, cover with soil. ③ chose to spray 0.5% ferrous sulfate solution or 500 times of yellow leaf fast green plant antiviral compound nutrient solution to the leaves before sunrise in the morning or after 4: 00 p.m., about 7-10 days apart.