Efficient planting technique of asparagus twice Foster Mother Stem and three times asparagus in Pinghu, Zhejiang Province

Efficient planting technique of asparagus twice Foster Mother Stem and three times asparagus in Pinghu, Zhejiang Province

Fund projects: national bulk vegetable Industry Technology system Project (CARS-25), key Laboratory Project of Horticultural crop Biology and Germplasm creation of the Ministry of Agriculture

Pinghu City is located in Hangjiahu Plain with mild climate, fertile soil and four distinct seasons. The annual frost-free period is more than 200 days (days), which is suitable for the growth of asparagus and other crops. Pinghu began to plant asparagus in 2003. on the basis of using mushroom residue waste to improve and fertilize the soil, popularize and apply the "rice-mushroom-shoot" circular production model, that is, the rice straw produced after rice planting and harvest is used as the culture material for mushroom cultivation. The mushroom residue waste produced after mushroom planting is used as the base fertilizer for asparagus planting by ripening composting and fermentation, and asparagus two times raising mother stem and three times collecting asparagus (that is, keeping mother stem twice in spring and autumn, three times in spring, summer and autumn). In the process of production, ecological circular cultivation techniques such as rain shelter cultivation, application of organic fertilizer, integrated and efficient water-saving irrigation of water and fertilizer, and clean production of mother stem are applied. Reduce the use of chemical fertilizers and pesticides, protect the ecological environment, and realize the coordinated development of production and ecology. At present, the planting area of asparagus in Pinghu reaches 603.6 hm2 (9.054 mu), which is the main asparagus production base in Zhejiang Province. In 2017, Pinghu adopted the cultivation technique of 2 times raising mother stem and 3 times collecting bamboo shoots. The average yield of commercial tender bamboo shoots per 667m2 was 1570 kg, the output value was 12,899 yuan, and the benefit was 5340 yuan, which was more than 10% higher than that of traditional asparagus planting. Pinghu fresh asparagus is welcomed by consumers and marketers because of its thick stem, tender bamboo shoots and sweet and waxy taste. 90% of the products sell well in Shanghai, Hangzhou, Suzhou and other cities, and are exported to Beijing, Hong Kong and other places, with remarkable social and economic benefits. In this paper, the efficient planting techniques of two times raising mother stem and three times of collecting asparagus in Pinghu are introduced in detail as follows.

1 Variety selection

1.1 the F1 two-hybrid asparagus variety introduced by Grande from the United States has a large stem, uniform thickness, straight strips, compact scales, tall plants, strong growth potential, high yield and good stability. The tender stem is green, crystal clear, smooth and tastes good. The biggest advantage is that it has a good comprehensive shape and can meet the requirements of fresh market and processing export in many aspects.

1.2 Green Dragon introduced from the United States, high quality and high yield, delicate texture of tender stem, good green color, uniform thickness, high branching point, strong resistance, suitable for processing and fresh sale. The tender stem is hypertrophy, bright green, neat in size, tightly wrapped in apical scales, the height of the first branch is 48.1 cm, and the rate of scattered head is low. It has good adaptability, strong resistance, is not susceptible to disease, and has strong resistance to root rot and stem blight. The dormant period is short, so it is suitable for cultivation in open field and protected field.

1.3 the first generation of hybrids introduced from the United States in California have strong growth potential, tall plants, short dormancy period, good early harvest, about 10 days (days) ahead of the general varieties, long harvest period and good high yield. The stem of this variety is uniform and dark green, the lavender part is less, the bamboo shoot tip is conical and the scales are tightly wrapped.

2 raising seedlings

2.1Paddy soil was prepared with nutritious soil and mixed with 5 kg superphosphate per cubic meter of soil, crushed by machine and mixed well, then packed into a nutrition bowl of 10 cm × 10 cm for use. Commercial seedling substrate can also be purchased directly.

2.2 after washing, the uncoated seeds were soaked in 55-60 ℃ warm water for 15 min (min) and stirred continuously, then soaked in 25-30 ℃ normal temperature water for 72 h (h).

2.3 sowing time: from early March to early May in spring, from mid-May to early July in summer, and from mid-August to mid-September in autumn. Autumn sowing is mainly used in production, and the amount of seed used in every 667 m2 field is 45g to 60g. The seedlings were raised in a nutrition bowl with a seedling bed width of 1.1 m. Two days before sowing, the soil was watered with 600 times of 50% carbendazim wettable powder, and 1 seed was sown in each bowl. After sowing, the medicinal soil was covered with seed, and the medicinal soil was prepared according to the proportion of 10 g of Duofu wettable powder mixed with 20 kg fine soil, and it was pre-wet two days before sowing, and the thickness of covering seed was about 1 cm. After sowing, it was covered with plastic film to keep moisture. Raise seedlings in spring to keep warm in a small arch shed, and cover sunshade net in autumn to cool down. It can also be used to raise seedlings in acupoints.

2.4 Seedling bed management keep the bed soil moist after spring sowing, and after 20% of the seedlings are unearthed, the plastic film can be removed to prevent the seedlings from being injured too late. After the emergence of more than 70% of the seedlings, the small arch shed should be ventilated in time to prevent the temperature in the small arch shed from being too high during the day (more than 30 ℃) and keeping the night temperature above 13 ℃. When the air temperature is stable at 20 ℃ and the seedling height is 20 cm, the small arch shed film should be removed in time or the method of ventilation should not be uncovered to enhance the light. 7 days before transplanting, the seedlings should be ventilated and transparent, and the temperature should be 25: 30 ℃. Two days before transplanting, the 1000-fold solution of carbendazim wettable powder plus 10% imidacloprid wettable powder can be sprayed to control diseases and pests, and transplant with medicine. The sunshade net is covered outside the autumn sowing greenhouse, and the seedling bed and the sunshade net of the small arch shed are used for double shading and cooling. The small arch shed should be ventilated in time to prevent the seedlings from burning when the temperature in the small arch shed is too high (more than 35 ℃) in the daytime, and it can be planted when the ground temperature is more than 15 ℃ in the following spring.

Water management: if the soil in the nutrition bowl turns white, be sure to water thoroughly in the morning or evening on a sunny day, and water again after 7 days (days). 45-60 days after sowing in spring and summer, the seedlings had 3-4 branches and were planted when the plant height was more than 25 cm.

3 colonization

3.1 soil preparation is generally 10-15 days (days) before planting. The sandy soil blocks with deep and loose soil layer, rich in organic matter, low groundwater level, good drainage and irrigation and pH 6-8 should be selected. The texture of Pinghu soil is sticky and can be improved by mushroom residue waste with rich nutrition. The mushroom residue waste was collected for composting in May and July. In principle, the compost size should be 2 m wide and 1.5 m high, with unlimited length, turning the material once every 15 days (days), turning the material for 3 times in the whole process, and applying it to the soil as base fertilizer after the fermentation was completed from August to December. Generally, 3 000 ~ 5 000 kg was applied every 667m2, and the land was leveled after being deeply turned into the soil.

GP-C622, GP-C825, GP-C832 monomer or multi-span steel greenhouse was selected to carry out the whole process of rain shelter cultivation. Four rows of asparagus were planted in 6 m wide greenhouse, the distance between the planting center of the first row and the fourth row of asparagus and the edge of the greenhouse was about 1.0 m, and the distance between the first row and the second row of asparagus, the third row and the fourth row of asparagus was 1.4 m. The distance between the planting center of the second row and the third row of asparagus is 1.2 m. Six rows of asparagus were planted in 8 m wide greenhouse, the distance between the first row and the sixth row of asparagus and the edge of the greenhouse was about 1.0 m, and the distance between the planting centers of 6 rows of asparagus was about 1.2 m. The plant spacing was controlled at 25 cm ~ 40 cm ~ 2 and 1 111 ~ 1 780 plants per 667 m ~ 2 in 8m wide greenhouse and 667 m ~ 2 greenhouse respectively. During planting, a planting ditch with a depth of 10-15 cm was opened in the middle of the border (60 cm wide), and 3% phoxim granules were applied to control underground pests, with a dosage of 3-4 kg per 667m2. The scale buds of the seedlings were planted in the same direction, the roots were stretched, the soil thickness was 5 cm, and the planting border was watered within 3 hours (hours) after planting.

4 Management in the first year after planting

Autumn sowing was mainly used in production, and commercial bamboo shoots were not collected before cutting mother stems in summer in the following spring, and 3-4 mother stems per plant were left after cutting mother stems in summer. Combined with summer cutting mother stems to clear the garden to loosen soil, Israeli potassium calcium nitrate (N-P-K-Ca = 15-5-35-25, the same below) water soluble fertilizer was applied for 7 kg every 15 days (days). Commercial bamboo shoots can be harvested after leaving the mother stem for 30 days. During the period of bamboo shoot harvesting, topdressing was applied once every 15 to 20 days (days), and 7 kg of Israel potassium nitrate calcium precious water soluble fertilizer was applied every 667m ~ 2 for 6 times.

5. Field management

5.1 Water management advocates the use of micro-drip irrigation to save water. During the growth period of asparagus, the soil water content around the eyedropper on the planting bed is moist, but there is no water in the ditch, and it is appropriate to walk in the ditch without soil on the sole.

5.2 Fertilizer Management according to the growth and development needs of asparagus and the characteristics of integrated water and fertilizer application, winter sprouting fertilizer, summer shoot fertilizer and autumn fertilizer are mainly applied throughout the year, and applied in the form of water-soluble fertilizer through micro-drip irrigation, which can save labor and improve fertilizer efficiency. Summer shoot fertilizer after the spring mother stem remained to grow up: after the spring mother stem remained to grow up from the middle of May to the first ten days of June, Israel potassium nitrate calcium precious water soluble fertilizer was applied for 7 kg every 667m2, once every 15 days (days), twice in total. Autumn hair fertilizer after clearing garden in summer: combined with loosening soil in summer, 7kg was applied every 667m ~ 2, once every 15 days (days), twice in total. Sprouting fertilizer in the middle and last ten days of December: combined with the ploughing and loosening soil after clearing the garden in winter, 1 500 × 2000 kg of mushroom residue organic fertilizer, Shima brand potassium sulfate compound fertilizer (N-P-K = 15-15-15) 50~60kg and vegetable cake fertilizer were applied per kg. After fertilization, ditches were opened to smooth the border surface.

During the period of asparagus picking, according to the growth of asparagus mother stem or the situation of asparagus harvesting, 7 kg of Israel potassium nitrate calcium precious water soluble fertilizer was applied every 667m ~ 2, once every 15 ~ 20 days (days), for a total of 6 ~ 8 times. The integrated technology of water and fertilizer can reduce the humidity in the greenhouse and effectively control the occurrence of asparagus root rot, but the drip irrigation belt should not be too close to the root of asparagus. Generally, the drip irrigation belt should be placed 15 cm away from the root of asparagus to prevent the root rot of asparagus caused by waterlogging in the rhizosphere.

5.3 Plant management

5.3.1 the mother stem of spring asparagus was collected from late March to the first and middle of April, and the tender stem with strong growth, disease-free spot spot and thicker stem (about 1 cm in diameter) was retained according to the market situation. The number of asparagus in two-year-old and over-three-year-old asparagus was 3 and 4, respectively. The retained mother stem is required to be evenly distributed. When the plant height is 1.3 to 1.5 m, the core is removed and the residual leaves are removed. Generally, a 1.3 m high wood (bamboo) pile is erected every 1.5 to 2.0 m. When the local upper stem is formed, use cloth strips or nylon rope to cover the aboveground stem between the two stakes, and let the branches and leaves spread naturally, and do not tie the plants together.

5.3.2 keep the autumn mother stem from mid-June to early August, clear the garden in summer according to the time of picking asparagus in summer and weather conditions, and pay attention to avoid the high temperature season in late July. When clearing the garden (you can choose to clear the garden mechanically) cut the aboveground plants and weeds on a sunny day, and move out of the asparagus field for centralized treatment. After loosening the soil, asparagus and the surrounding soil were irrigated with more than 40% mn-Zn wettable powder 600 times and other fungicides to disinfect the soil.

After clearing the garden in summer, the autumn mother stem was kept, the asparagus of one or two years old left 3-4 per plant, and each plant of more than 3-year-old left 4-5. When the asparagus plant height is 1.5 m in 8 m wide greenhouse and 1.3 m in 6 m wide greenhouse, stand and pull double lines in time to prevent lodging.

5.4 in winter, the garden was cleared in the middle of December after the aboveground plants of asparagus withered completely, and the fine weather was selected when the garden was cleared. the greenhouse king four-wheeled tractor was installed with 4JQ-130 straw shredding and returning machine instead of manual cutting of mother stalk (figure 1). Mechanical garden cleaning can deal with 867.1 m2 of asparagus straw per hour, saving labor more than 5 times, and the mother stem is concentrated in the waste treatment area for fermentation. After clearing the garden, pay attention to do a good job of soil disinfection. Before disinfection, remove 23 cm of the topsoil around the asparagus tree plate and sun for 2 days, and then irrigate the asparagus tree plate and the surrounding soil with more than 40% manganese zinc wettable powder or 45% stone-sulfur mixture.

Fig. 1 using straw shredding and returning machine to mechanically cut the mother stem to clear the garden

Fig. 1 using straw shredding and returning machine to mechanically cut the mother stem to clear the garden

(6) Disease and pest control

6.1 the main pests of asparagus include beet armyworm, Spodoptera litura, thrips and aphids, among which beet armyworm is the most serious. There are 6 generations of beet armyworm and 5 generations of Spodoptera litura every year. July to October is the peak of damage to two species of Spodoptera exigua pests, mainly the 3rd, 4th and 5th generations. The larvae can harm the young stem of asparagus, the green part of the aboveground stem and the pseudo-leaf, etc. when the damage is serious, the young stem can not germinate normally and deformed, and all the green part of the aboveground stem and pseudo-leaf are killed. Insect sex traps can be used to trap and kill night moth pests. One or two special traps are suspended in every 667 m2 greenhouse, and the suspension height should be slightly higher than that of the asparagus mother stem, and should be adjusted in time with the height of the mother stem. For young larvae, 20% chlorobenzamide suspension is 3000 times, the safe interval is 1 day, 15% indenyl suspension is 3000 times, the safe interval is 3 days, 6% ethyl spinosad suspension is 2 500 times, the safe interval is 5 days. 10% mifenil suspension solution 1000 times, the safe interval 10 days (days), etc., the above agents were sprayed 1 times twice depending on the condition of the insect. Weeds such as amaranth in the greenhouse are also the main hosts of beet armyworm and other pests, so they should be sprayed together.

Thrips and aphids can be trapped and killed by color plate. Yellow board and blue board have significant trapping and killing effect on thrips, among which the blue plate is the best. When the mixture of thrips and aphids occurs in the field, yellow board can also be used to trap and kill two kinds of pests. The hanging height of the color plate should be slightly higher than that of the mother stem of asparagus, and should be adjusted in time with the height of the mother stem.

Every 667m2, 3040 blue (yellow) plates of 25 cm × 40 cm were suspended. At the initial stage of the occurrence of thrips, 6% ethyl spinosad suspension 2 500 times or 10% bromocyanide dispersible oil suspension 2 000 times can be sprayed with a safe interval of 7 days. At the initial stage of aphid occurrence, 70% imidacloprid water dispersible granule 15000 times or 10% bromocyanide dispersible oil suspension 2000 times can be sprayed with a safe interval of 7 days (days), only once.

No underground pests such as small land tiger have been found to damage asparagus in Pinghu. According to the author's investigation, beet armyworm is the main damage to the base of asparagus, and its larvae can be eaten at the base of asparagus, which is often mistaken for small land tiger. Pay attention to ground spray during prevention and control.

6.2 the main diseases to control asparagus include root rot, stem blight and so on.

Root rot: under the cultivation mode of shelter from rain in greenhouse, the incidence of root rot of asparagus is the most serious, which can occur in all growing seasons of asparagus, especially in the rainy season with high temperature. The tilt angle of the greenhouse should be close to 90 °. If the tilt angle is slow, the spatter of Rain Water will lead to the serious occurrence of asparagus root rot on both sides of the greenhouse. On the basis of clearing the garden in winter, soil disinfection should be carried out in time. In individual plots with root rot, the roots can be drenched with 500x carbendazim wettable powder or 0 Bacillus subtilis wettable powder containing spores. The diseased plants with seriously rotten roots were treated in time, and the soil was disinfected with 50% carbendazim wettable powder 500 times after digging. Rain Water is the carrier of bacterial spore transmission, and avoiding water transmission is the key to prevent the occurrence of asparagus root rot. Therefore, on the basis of rain shelter cultivation, measures such as opening ditches to reduce humidity, lowering the groundwater level, and removing stagnant water in time when the rainy season comes.

Stem blight: before or at the initial stage of asparagus stem blight, 10% difenoconazole water dispersible granules 1 000 × 1 500 times, safe interval 15 days; or 80% mancozeb wettable powder 500 times, or 65% mancozeb wettable powder 350 times, or 70% thiophanate 600 times wettable powder and other foliar spray, safe interval 7 days (days), spray 2 times 3 times depending on the disease. The mother stem can also be smeared with 50% carbendazim wettable powder 50 times or 25% azoxystrobin suspension 100 times.

6.3 Prevention and control of physiological diseases during the growing period of asparagus, the tender stem will crack, split longitudinally into brown deep mouth, and cause rot. It is mainly a physiological disease caused by the imbalance of water supply in the soil and the sudden watering of the soil after a long period of drought. The key to prevent cracking is timely watering to keep the soil water content relatively stable and to prevent sudden dryness and humidity.

7 harvesting

Asparagus can be harvested in the same year after planting, generally entering the peak period in the third year, and can be harvested continuously for 15 years and 20 years. The tender stems on the ground can be harvested when they grow to about 30 cm, and they are usually harvested with a special asparagus shovel in the morning. Young stems grow fast in high temperature season, and can be harvested twice a day in order to ensure quality. The asparagus harvested were graded and packaged according to customer requirements, which were generally divided into three grades: stem diameter 0.8 cm (long 22cm), 0.8 cm 1.2 cm (26 cm long), and 1.2 cm (long 32cm).

Spring bamboo shoots are harvested every year in spring, summer and autumn. Spring bamboo shoots are harvested in February and March. The output is 300,400 kg per 667m2, accounting for 30% of the annual output, and the output value is 4,000 to 5,000 yuan, accounting for 40% of the annual output value. Summer bamboo shoots are harvested in May and August, with an output of 600,700 kg per 667m2, accounting for 45% of the annual output, with an output value of 3,400,000 yuan, accounting for 30% of the annual output value. Autumn bamboo shoots are harvested in September and October, with an output of 400,500 kg per 667m2, accounting for 25% of the annual output, with an output value of 3,200,000 yuan, accounting for about 30% of the annual output value. In total, the annual yield of tender bamboo shoots per 667m2 is about 1500 kg, the output value is about 13000 yuan, and the benefit is about 5300 yuan.