Cultivation techniques and management of konjac

Amorphophallus konjac, nicknamed _ _, is a perennial herb of Araceae. Amorphophallus konjac was cultivated in China more than 2,000 years ago, and its edible history is quite long, mainly distributed in Yunnan, Guizhou, Sichuan, southwestern Shaanxi and western Hubei. With the development and utilization of konjac, konjac cultivation has a good development prospect. Let's take a look at the high-yield cultivation techniques of konjac!

Land selection and preparation

Konjac has strict requirements on light, heat, water and fertilizer, and must be planted in suitable places and soil. We should choose the slightly acidic to neutral (pH 6.5 ~ 7) soil with thick and loose soil layer and good drainage, and the gentle slope land containing a small amount of gravel, light soil and bubble soil is the most suitable for planting konjac. Before planting konjac, it is necessary to explore Kangtu as soon as possible to remove stones, weeds and residual films from the soil.

Seed taro treatment

1. Seed taro production: To develop konjac production, we must first develop seed taro production and prepare enough seed taro. Disinfection of taro seeds, isolation of dung seeds, timely chemical control and timely eradication of diseased plants. To develop taro production, we must adhere to the local self-propagation of taro and give priority to taro farmers. New development households should first develop taro planting, and old growers should match the corresponding taro planting area. Improve that quality and safety of seed taro. The ratio of seed use area to field area is generally 1:3.

2. taro disinfection: taro disinfection is to eliminate the germs on taro from the source. First, dry the seeds in the sun, and spread them for 2 days before sowing. The second is seed soaking, that is, soaking seeds with 500ppm streptomycin sulfate solution for 30 minutes in sunny morning, taking them out and sowing immediately after drying, or dressing seeds with kitchen ash (wood ash), drying and sowing. Where conditions permit, the sun-dried and soaked seed taro should be transplanted to the field after seedling raising and germination.

3. Sowing method: When sowing, taro and fertilizer are isolated from each other and cannot be in direct contact. In order to ensure the safe emergence of Amorphophallus konjac, the method of sowing in the sowing ditch first, covering the soil and then fertilizing was adopted. Spraying agricultural streptomycin or Monctonia as preventive and protective drugs before the onset of konjac after emergence. Once a diseased plant appears in the field and the dew dries on a sunny day, dig out the diseased plant with roots and soil in the nest and disinfect it with lime. Don't take sick plants home as raw feed for pigs or throw them around at will, causing artificial spread.

Scientific fertilization

1. Fertilization principle: Amorphophallus konjac is a chlorine-free tuber crop and needs a lot of fertilizer. It has the characteristics of being fond of fat and afraid of being thin, potassium and chlorine. It needs the most potassium fertilizer, followed by nitrogen fertilizer, phosphorus fertilizer and trace elements such as calcium, zinc, magnesium and manganese. Therefore, we must adhere to the principle of giving priority to base fertilizer and then applying farm manure.

2. Base fertilizer management: For konjac land with low soil fertility, more than 2,000 kilograms of farm manure such as washer fertilizer, high-quality soil fertilizer and lawn fire fertilizer should be applied per mu. In the base fertilizer, according to the soil nutrient status, 2 ~ 4 kilograms of biological potassium fertilizer is applied, and fertilizers such as urea, superphosphate or calcium magnesium phosphate fertilizer are appropriately applied.

3. Fertilizer selection: it is forbidden to apply sick and disabled farmyard manure, chicken manure and chlorine-containing chemical fertilizer, and it is not allowed to apply more nitrogen fertilizer. Applying farm manure in large quantities and chemical fertilizer as little as possible is not only beneficial to improving soil fertility and improving soil, but also can make konjac grow steadily and firmly and enhance its disease resistance.

4. Rational topdressing

(1) When the first topdressing reaches about 80% of konjac seedlings, if the base fertilizer is insufficient, the seedling fertilizer should be applied again, with 20-30 loads of human manure and 40 loads of water per mu, and about 5 kg of urea, 5 loads of human manure and 5 loads of water per mu with sufficient base fertilizer.

② During the second topdressing from the end of June to the beginning of July, 6-8 kg of urea and 0/5-20 kg of potassium sulfate/kloc were mixed with high-quality farm manure such as washer fertilizer or fire fertilizer, and cultivated in shallow soil.

(3) Top dressing the tuber swelling fertilizer for the third time from late July to early August, covering holes with 20-30 kilograms of potassium sulfate per mu, and spraying 0.2% potassium dihydrogen phosphate solution on leaves for 2-3 times from August to September.

Tiantuan management

1. Covering management: After Amorphophallus konjac is sown, it is necessary to collect various covers such as stalks, pods and dead leaves. And it is best to spread the plastic film evenly, evenly and tightly on the konjac ground to achieve the standard of "no grass covered, no ground exposed". Generally, about 2000 kilograms of plastic film is needed per mu, after September.

2. Weed removal: Amorphophallus konjac root system is shallow. In order to prevent intertillage weeding from damaging developing young roots and underground stems and affecting the normal growth of plants, manual weeding can be used. However, it should be noted that people can only squat in the furrow to pull grass, and don't step on the ridge surface to avoid crushing the underground roots.

3. Clear the ditch and cultivate the soil: Amorphophallus konjac is not only afraid of drought, but also not suitable for soaking. Therefore, in the rainy season, especially after the rainstorm, it is necessary to inspect the planted fields in the field and drain the ditches to ensure the smooth waterway. Combined with ditch cleaning, fine soil in the ditch is cultivated on the ridge surface, and the soil is cultivated for 2 ~ 3 times in the growing period, which is beneficial to the formation and expansion of bulbs and the exposure of taro, and enhances the wind resistance of konjac.

control of insect

1, soft rot

Symptoms mainly affect petioles, bulbs and leaves. After injury, their tissues turn black and soft, stink, and even rot and lodging, causing huge losses.

The cultivation management should be strengthened, and deep ploughing, drainage and ventilation should be carried out regularly for the prevention and control of planting konjac. When selecting seeds, we should carefully select taro without rot and wound, and properly keep and transport it. In addition, it should be noted that Amorphophallus konjac has vegetable crops that cannot be continuously planted or interplanted, such as Solanaceae. Before planting konjac, it can be soaked in an appropriate proportion of agricultural streptomycin solution, taken out and dried.

2, white silk disease

Symptoms mainly affect the base of petiole, resulting in petiole or bulb damage. When the petiole is infected with white silk disease, dark brown spots will appear and expand continuously, and finally white filamentous hyphae will grow on the petiole, which is reddish.

In order to control white silk disease, it is necessary to strengthen the cultivation management in rural areas and drain the accumulated water in time. During the planting period, continuous cropping and intercropping with peanuts, solanaceae and soybeans are not allowed. At the same time, the periphery of the petiole in contact with the soil surface can be sprayed and disinfected with Bordeaux solution in a proper proportion during the period from konjac modification to bulb expansion.

3. Leaf blight

Symptoms mainly harm leaves. Pathogens overwinter in the soil and can splash on leaves with rain. In addition, it can also invade through wounds or pores and spread through wind and rain. Therefore, the bacterial infection ability of leaf blight is very strong, which leads to the withering and death of konjac.

The control measures of leaf blight are basically the same as soft rot.

4. Pests

The pests whose symptoms affect the growth of konjac mainly include sweet potato moth, konjac nematode, bean moth and so on.

To control these pests, weeds and dead leaves need to be removed in winter and spring, and interplanting konjac and corn in the field plays an important role in pest control. In addition, pesticides can also be used to artificially remove pests, and attention should be paid to choosing decomposed farmyard manure when using farmyard manure.