The paper introduces the main types of sweet potato pests in Nanchong City, as well as green prevention and control technical measures such as agricultural prevention and control, physical prevention and control, physical and chemical inducement control, biological prevention and control, and scientific drug use.
Sweet potato (Dioscorea esculenta (Lour.) Burkill), also known as sweet potato, potato family potato genus winding grass vine, in china there are many aliases, sweet potato, sweet potato, sweet potato, sweet potato, sweet potato, sweet potato, sweet potato, Sichuan also known as red amaranth. Sweet potato underground tubers at the tip of the branch ends of the enlarged ovoid tubers, the outer skin is yellowish, smooth; The stem is left-handed, with spines at the base, and is thong-shaped with soft hairs; Single-leaf alternate, broad-heart-shaped; The male inflorescence is a spike-like inflorescence, solitary, and the male flowers are stalkless or have very short stems; The bracts are ovate and tapering at the apex; The flowers are shallow cup-shaped and covered with short soft hairs; Triangular in the capsule, slightly concave at the apex, truncated at the base, each ridged wing-like; The seeds are round and winged; Flowering occurs in early summer.
Sweet potato is a light-loving short-day crop, warm-loving, not hardy, more drought-tolerant. It is mainly distributed in the south of 40° north latitude, with the largest cultivation area in Asia, followed by Africa, and the Third In the Americas, and is widely cultivated in more than 111 countries and regions in the world. In recent years, the international community has paid more and more attention to the unique nutritional and health care function of sweet potato, and the "sweet potato edible fever" has quietly emerged, which is of great significance for the development of China's sweet potato industry and the promotion of agricultural industry restructuring.
Nanchong sweet potato cultivation area is second only to rice, wheat and corn, accounting for 4th place, in 2019 planting area of 64,900 hm2, the total output of 287,000 t (folded raw grain). The yield per unit area of sweet potato is very high, and the yield of fresh potatoes in set cropping and net cropping is generally 22500~37500kg/hm2. However, sweet potato pest control is also less in Nanchong. In this regard, the author in order to do a good job in the green prevention and control of sweet potato diseases and insect pests, reduce the loss of diseases and insects, and ensure the safety of sweet potato production, sweet potato quality and environmental safety. In recent years, the green prevention and control test demonstration of the main sweet potato diseases and insect pests has been carried out in Nanchong, and good results have been achieved. This paper introduces the green prevention and control technology of sweet potato diseases and insect pests, in order to provide a reference for guiding the green prevention and control of the main sweet potato pests in Nanchong.
<h1 class = "pgc-h-arrow-right" >1, the main diseases and pests of sweet potatoes</h1>
According to the survey, the main diseases and insect pests of Nanchong sweet potato are sweet potato soft rot, sweet potato dry rot disease, sweet potato virus disease (also known as sweet potato mosaic disease), sweet potato black spot disease, sweet potato spot disease, grub (grub is the larvae of scarab beetles), small land tiger (larvae commonly known as soil silkworms, ground silkworms, root-cutting insects), crickets, sweet potato leaf beetles (also known as sweet potato leaf worms, sweet potato monkey leaf worms, blue black gold flower worms, sweet potato golden flower worms, etc.), sweet potato moths, sweet potato wheat moths, etc.
<h1 class="pgc-h-arrow-right" >2, the main prevention and control technical measures</h1>
2.1 Agricultural prevention and control
2.1.1 Promote resistant and disease-resistant varieties The agricultural authorities and scientific research departments of Nanchong City recommend the selected sweet potato varieties that are resistant to (resistant) black spot disease, viral disease and cranberry disease, such as Yushu 17, Nanzi potato 008, Guangshu 87, Xicheng potato 007, etc.
2.1.2 Implement standardized crop rotation Wheat/jade/potato, wheat/flower/potato can implement "83cm", "100cm" or double "166.7cm", double "200cm" retention. Sow the first 83, 100, 166.7 or 200 cm of wheat or sow wheat in the autumn of that year, plant sweet potatoes after wheat harvest, and reserve a blank row of 83, 100, 166.7 or 200 cm (can grow vegetables, peas, beans, etc.), and sow corn or peanuts in March of the following year; Autumn sowing rotation in the second year.
2.1.3 Plough potato fields to reduce the source of insects In winter and spring, cultivate more raked sweet potato plots, destroy their overwintering environment, kill overwintering pupae, and reduce insect sources.
2.1.4 Strengthen fitness cultivation, improve resilience Select disease-free seed potatoes and disease-free land as seedbeds, hotbed seedlings or mulching seedlings SbddJ + BCKwKM8cK56vzHW== seedlings, strengthen seedbed inspection, find diseased seedlings, and dig out together with potato blocks to ensure that diseased seedlings are not planted in the field; Cultivate strong seedlings, select disease-free healthy seedlings, promote ridge cultivation, timely and early planting, reasonable dense planting, scientific fertilization, increase phosphorus and potassium fertilizer, weeding in medium cultivation, sweet potato growth stage, spray 150g/hm2 95% potassium dihydrogen phosphate + urea 7.5~15kg/hm2 foliar spray 2 to 3 times, each interval period of 10d. Harvest at the right time, enter the cellar at the right time, and avoid frost damage. Establish disease-free planting fields and leave seed potatoes from disease-free plants.
2.1.5 Establish a land for disease-free seedlings to be planted Select a plot of sweet potato that has not been planted for 3 years as a seed retention land. Cut the seedlings from the spring potato vines to insert summer potatoes or implement high-shear seedling cuttings for seeding, apply disease-free manure, purify water, and pay attention to the prevention and control of underground pests. Single receipt, single transport, single storage, and to prevent contagion in transport and storage.
2.1.6 Harvest at the right time to avoid frost damage Summer potatoes should be harvested before frost falls, and autumn potatoes should be harvested before winter. Potato harvesting should be carried out on a sunny day, carefully harvest potatoes to avoid wounds.
2.1.7 Safe storage Before the storage of sweet potatoes, it is necessary to strictly eliminate diseased, frostbitten and injured potato blocks. Before entering the cellar, clean the potato cellar and disinfect and sterilize. The old cellar should be cleaned or the cellar wall should be planed with 1 layer of soil and then fumigated with sulfur (sulfur 15g/m3). After entering the cellar, pay attention to the dispersion of temperature and humidity, strictly control the temperature of the cellar at 10 ~ 14 ° C, humidity in 80% ~ 85%. It is necessary to strengthen storage management and pass the three levels of high temperature sweating, overwintering and low temperature, and yang warming. First, the management of high temperature sweating period. That is, about 20 days after entering the cellar, it is necessary to open the ventilation holes, cellar openings, doors and windows of the cellar, do a good job of cooling and exhausting, prevent the cellar temperature from rising, and control the black spot disease. The second is wintering management. After entering the winter, the cellar temperature drops, to seal the gas hole and the cellar mouth, in order to keep the cellar temperature at 10 ~ 14 ° C, when the cellar temperature is lower than 10 ° C, pay attention to the potato pile covered with straw or wheat straw and other things, to prevent potato blocks from being cold, frost damage. The third is post-spring management. After the beginning of spring, the temperature rises, when the cellar temperature rises to more than 13 ° C, attention should be paid to opening the cellar mouth and ventilation hole on a windless sunny day to cool down and exhaust.
2.2 Physical prevention and control
2.2.1 Light traps adult insects Insecticidal lamps can be installed in areas with better infrastructure conditions depending on the sweet potato environment. It can be installed according to 1 lamp per 2.7 to 3.3hm2 in the Pingba area, 1.33 to 2.0hm2 1 lamp in hilly mountains, the bottom of the insecticidal lamp is 1.5m from the ground, and the insecticidal lamp traps the adult insects such as sweet potato moth, wheat moth, small land tiger, scarab beetle (grub), which can significantly reduce the density of its insect population and reduce the degree of occurrence. The booby-trap is turned on from the beginning of April to the end of September. Lights are turned on daily from 19:00 to 1:00 the following day.
2.2.2 Artificial killing First, kill the adult sweet potato goldenrod. Using the suspended death and activity habits of adult insects, it is advisable to concentrate on hunting at dusk and early morning, when most pests gather on young stems and leaves to feed. The second is paulownia leaves booby traping the larvae of small ground tigers. Small ground tiger larvae have a tendency to paulownia leaves, when the sweet potato is damaged, you can take the older paulownia leaves, soaked with water, placed in the sweet potato field in the evening, 1200 to 1800 paulownia leaves per hm2, the leaves are opened early on the second day to catch the larvae, and the effect of one leaf release can be maintained for 4 to 5 days. It can also be caught in the soil near the affected plant in the early morning. Early combined with field management, the larvae of sweet potato moths and wheat moths were killed.
2.3 Physicochemical inducement control
2.3.1 Booby traps with sweet and sour liquids
Adult tigers in small land have a strong tendency to sweet and sour liquid, and generally use this method to trap and kill in mid-to-late April, and the effect is better. According to the sugar: vinegar: white wine: water: 90% crystal enemy insect ratio of 6:3:1:10:1 mixed well, placed in the basin, every hm2 put 15 pots, height 1.0m, replenished 1 time a day sweet and sour solution, at the same time, take out the booby traps of pests.
2.3.2 Bait booby traps
Small ground tigers and moths can be booby-trapped with poisonous bait. First, sauté 5 kg of wheat bran or rapeseed cake over low heat, add 90% crystalline insects 50g and a small amount of water to mix well, or 10% imidacloprid wettable powder 1000 times liquid, and sprinkle in the sweet potato field in the evening for booby traps. The nectar habit of adult sweet potato moths is used to trap them with syrup bait during the adult season, or to hunt in places with more sources of honey to reduce the amount of eggs in the field. If the above paulownia leaves are first immersed in 90% crystalline dimethods 150 times the liquid, and then put into the sweet potato field, the small ground tiger larvae can be directly killed, and the medicinal effect lasts for about 7 days.
2.3.3 Sexual pheromone booby-traps
Use sex pheromones to trap adult sweet potato wheat moths. The peak period of release pheromones is 1 to 3 days after the feathering of sweet potato wheat moth, especially on day 2, so prepare before the peak of adult insects. The height of the trap can be slightly higher than the sweet potato, generally not higher than 10 cm.
2.4 Scientific use of medicine
2.4.1 Sweet potato soft rot and sweet potato dry rot
Before seeding potato blocks into the cellar, use 5% sucrose lipid ester wettable powder 300 to 400 times liquid, or 50% methylthiopramine wettable powder 500 to 700 times liquid, or use 50% carbendazim wettable powder 500 times liquid, dip the potato cubes 1 to 2 times, and dry them into the cellar. Or use imidamine manganese salt - sweet potato disinfection preservative 50g first with a small amount of water moistened stirring and then mixed with water 20 ~ 40kg (can disinfect 1000 ~ 2000kg potato block), soak the potato block for 1 ~ 3min after fishing out, drizzle off the liquid medicine and then store in the cellar; You can also put 1 layer of potato blocks in the cellar, spray 1 time medicine, and spray wet potato blocks; If the potato nuggets are already in the cellar, they can also be poured with medicinal solution.
2.4.2 Sweet potato virus disease
(Mosaic disease) Nanchong sweet potato virus disease is mainly sweet potato feathery mottle virus (SPFMV), also known as sweet potato green spot virus (SPCMV), sweet potato wood plug virus (SPICV), sweet potato schizophidity virus (SPRCV), sweet potato virus A (SPV-A) and so on. At the beginning of the disease, use 0.5% shiitake mushroom polysaccharide water agent 3000mL + Bihu wettable powder 600g, or 8% niyramycin water agent 900mL + Bihu wettable powder 600g, or 80% morpholine guanidine hydrochloride WG 900g + Bihu WP 600g mixed with water 450 ~ 675kg manual spray, or mixed with water 112.5kg mobile mi mist, or 5% mytoxic clear wettable powder 500 times liquid, or 20% virus Ning water-soluble powder 500 times liquid, or 15% Virus Bike wettable powder 500 ~ 700 times liquid spray, 7 ~ 10 days once, continuous administration of 3 to 4 times.
2.4.3 Sweet potato black spot disease
(1) Impregnation of seeds with medicinal agents. Soak the seed potato with 50% carbendazim wettable powder 500 times liquid for 5min, or 50% methylthiopyridine wettable powder 800 to 1000 times liquid soak the seed potato for 10min, and then dry it into the cellar, each agent is soaked in seed potato 10000kg per kg of liquid, and the efficacy of 10 consecutive soaks in seeds for 10 times is not reduced. It can also be mixed with 50% methylthiopramine (or 50% carbendazim) wettable powder and dichlorvos according to 1:1, mixed into 500 times liquid, directly sprayed on the surface of the seed potato, and the seed potato can be moistened to cover the soil or (sand) and treat pests. (2) Disinfection of seedlings with chemical impregnation. Use 50% methylthiophilin wettable powder 500 to 700 times liquid or 50% carbendazim 2500 to 3000 times liquid, dipped in roots 6 to 10 cm deep, with 2 to 3 min.
2.4.4 Sweet potato spotting disease
At the beginning of the disease, 65% daisen zinc wettable powder 400 to 600 times liquid, or 70% methyl thiophanomymid wettable powder 1000 times liquid spray prevention and control, 5 to 7 days spray 1 time, 2 to 3 times continuously.
2.4.5 Grubs
Grubs are larvae of scarab beetles. Roots can be irrigated with 50% octyl thiophos emulsion 1000 times liquid, or 15000kg of fine soil with 50% octyl thiophosphorus emulsion 15000mL per hm2, and evenly sprinkled into the plough bottom ditch when ploughing the ground. When controlling tigers and caddisflies, you can also use poisonous bait to trap: take 80% of the wettable powder of 80% of the enemy insects 60 to 100g, first add a small amount of water, and then mix well with the stir-fried vegetable cake 5 to 7 kg, and then put it into the field; Or use poisonous grass to booby trap: take 25 to 40 kg of fresh grass (the section of 1.7 cm of the growth of the grass), and then take 90% of the enemy insects 50g (add the appropriate amount of water and mix well), spray the liquid into the fresh grass, and sprinkle it on the root ground of the potato seedlings in the evening to trap it.
2.4.6 Small-ground tigers, crickets
Before the age of 3 years, each hm2 can choose 50% octylthion emulsion 750 mL, or 2.5% cypermethrin emulsion or 40% cypermethrin emulsion 300 ~ 450 mL, 90% crystalline dimethoate 750g, 450 ~ 675 kg of manual spray with water, or 112.5 kg of motorized mist with water, or 50% octyl thiophosphorus emulsion 4.5 kg with water 30 kg, mix dry fine soil 300 kg, evenly sprinkle around the potato seedlings; After the 3rd age of the ground tiger, if the damage is serious, use chopped fresh grass to mix 90% of the soluble powder of the enemy insects 800 times liquid, hm2 375 ~ 600 kg per hm, sprinkled on the potato ridge in the evening to poison.
2.4.7 Sweet potato leaf beetle (sweet potato goldenrod)
(1) Biologics. Spray the ground with 75 kg of green zombie agent per hm2 and then plough it into the soil, where the green zombie can parasitize the larvae and make it deadly. (2) Prevention and control of poisonous soil or poisonous fertilizer. 90% dimethoate soluble powder 750 ~ 1000g or 50% octylthiophosphorus emulsion 200 ~ 300mL, are mixed with fine soil 15 ~ 20kg evenly, withdraw the ground surface, or mixed with fertilizer, roll into the ground when ridged, can effectively kill the larvae. (3) Spray prevention and control. In the case of adult large occurrence, spray on potato seedlings or potato plants with 90% crystalline diphthiae soluble powder 1000 to 1500 times liquid, or 50% octylthion emulsion 1500 times liquid, or 0.6% matrine nicotine l000 times liquid, or 5% high performance cypermethrin emulsion 2000 times liquid, or per hm2 with imidacloprid 5% emulsion 900 to 1500 mL, or 10% wettable powder 450 to 750 g, 25% wettable powder 180 to 300 g, or 70% Water dispersible granules 75 ~ 105g mixed with water 450 ~ 675kg manual spray, or mixed with water 112.5kg mobile mist, sprayed every 5d or so 1 time, 2 to 3 times continuously, the effect is better.
2.4.7 Sweet potato moth When there are 3 to 5 pre-instar larvae per m2, or 2 worms per 100 leaves, it can be controlled by medicine. You can choose 1% methylaminoavermectin benzoate emulsion 1000 times liquid, or 20% chlorofuran benzamide suspension 5000 to 7000 times liquid, or 1.8% avermectin emulsion 1500 to 2000 times liquid, or 2.5% high efficiency cypermethrin emulsion 1000 to 1500 times liquid, or 5% fluling urea emulsion 1000 to 1500 times liquid, or use the compound preparation of the above agents for spraying, all of which have a good control effect on sweet potato moths.
2.4.8 Sweet potato wheat moth When a large number of larvae occur in 1-2 instars, it is immediately administered for control. You can choose 2% Avi Perchlorofluoroemulfan Emulsion 1000~2000 times liquid, or 2 avermectin emulsion 1000~2000 times liquid, or 2.5% high-efficiency cypermethrin emulsion 1000~2000 times liquid, or 5% fluoropyridine suspension 1000 times liquid, spray control in sunny and windless afternoons, about 1 time in 7 days, 2 to 3 times continuously.