Control techniques of Diseases and insect pests in Tiannanxing

Tiannanxing, alias Nanxing, Bai Nanxing, etc., is a perennial herb of the Araceae family. It is wild and can be cultivated in both north and south of China. Except for the northwest and Xizang, it is distributed in most provinces and regions below 2700 meters above sea level. Born under forests, bushes or grasslands, let's take a look at Tiannanxing's pest control techniques.

Viral disease

[harmful characteristics] Leaf symptoms are often characterized by mosaic, irregular chlorosis or yellow stripes, causing longitudinal curl deformity of leaf veins, dwarfing diseased plants, blocking leaf chlorophyll, affecting normal photosynthesis, affecting tuber yield and quality, caused by a variety of viruses, the virus can accumulate in the plant, some can be transmitted by aphids, the number of aphids in the field is large, and the disease is serious if the damage lasts for a long time.

[control methods] ① adopted virus-free technology, planted and propagated with virus-free seeds, and could also be propagated with non-toxic seeds. ② conditionally advocates the use of heat treatment combined with shoot tip detoxification to obtain virus-free seedlings. ③ found aphids and sprayed insecticides to kill aphids in time to reduce virus transmission.

Anthrax

[hazard characteristics] anthracnose is one of the main diseases in Tiannanxing planting area, which seriously affects the yield and quality of Tiannanxing, and mainly harms leaves, petioles, stems and fruits. The infected leaves are round or nearly round, with a size of 2-5 mm. The central part is gray-white to light brown, the edge is green to brown, the diseased parts are whorled or accumulate black spots, and the stems and petioles are infected with light brown fusiform sunken spots and dense black small spots. When the humidity is high, a large number of orange-red conidia accumulate on the conidium disk, and the berries are infected with reddish-brown sunken spots.

[agricultural control] reasonable close planting, pay attention to ventilation and ventilation, scientific formula fertilization, increase the application of phosphorus and potassium fertilizer, improve plant disease resistance, timely irrigation, strictly prohibit flood irrigation, timely drainage after rain, prevent excessive humidity, remove susceptible leaves in time, cut off the disease spots of lightly diseased leaves.

[pharmaceutical control] spray 1% Bordeaux solution or 27% high-fat membrane emulsion 100,200 times before onset. During the onset of the disease, you can choose 1000 times of 75% chlorothalonil, 20% tricyclazole and 50% anthrax Fumei, once every 7-10 days, several times in a row, fungicides should be rotated and the effect is better.

Root rot disease

[hazard characteristics] Root rot usually occurs from May to October. The injured plant tubers rot, leaves die, and spread rapidly.

[prevention and control methods] the stagnant water in the ground was discharged in the rainy season, the well water was poured in time after the hot summer rain to reduce the ground temperature, the carbendazim 1000-fold solution was sprayed to prevent it in summer, the diseased plants were dug up and burned in time, and the diseased holes were disinfected with quicklime.

Stem blight

[hazard characteristics] Brown annular depression, constriction, low temperature, high humidity and incorrect stubble occurred at the junction of corm and young stem under the surface of the base soil after the seedling was unearthed.

[prevention and treatment methods] the commonly used agents are 70% methyl topiramate wettable powder 500x, 75% chlorothalonil wettable powder 500x, spray once every 7 to 8 days, continuous spraying for three times, which can effectively control the disease. 75% chlorothalonil wettable powder was sprayed with 75% chlorothalonil wettable powder at the initial stage of the disease, or 38% carbendazim 800x solution, 64% Chlorothalonil wettable powder 400x or 50% prohydantoin wettable powder 1000 times Or 70% ethyl phosphine ·manganese zinc 500 times solution.

Epidemic disease

[hazard characteristics] the optimum temperature for the occurrence of soil-borne diseases caused by Phytophthora blight is 20-25 ℃, especially in the rainy season. The affected parts are flooded at first, and the tissue fades and browns. At the initial stage of infection, the diseased tissues still maintain considerable toughness, but the affected parts decay, collapse and disintegrate in the later stage.

[agricultural prevention and control] the most effective and simple measure for ① is to strengthen field hygiene management, to remove diseased plants, diseased leaves and weeds at any time, and to take them away from the park to burn, do not accumulate plant remains in the park, so as to avoid the breeding of pathogenic bacteria, and try to avoid rain, watering and splash. even after rain, medicine must be administered in time to prevent. ② strengthens the ventilation and cooling of the park, and nitrogen fertilizer should not be excessive.

[chemical control] 58% Metalaxyl-Zinc Manganese (Zinc Manganese) 400,600 times, 72.2% Pulicol Water Agent 800,800 times 1000 times, 50% Alcohol wettable Powder 1000 times 1500 times, 64% Zinc Manganese Naipu wettable Powder 400 times in turn.

Spodoptera litura

[hazard characteristics] the leaves were harmed by the larvae and bitten into gaps and voids. When it was serious from July to August, the leaves of Artemisia angustifolia were eaten.

[control method] when the larvae were young, ① was killed by spraying 90% trichlorfon 800-fold solution. ② should avoid continuous cropping and intercropping with plants of the same family, such as Pinellia ternata, konjac and so on.