After a long harvest in spring and summer, the nutrients stored in the roots of asparagus have been basically exhausted, the young stems that grow have become thinner, the fibers have increased, the quality and yield have decreased significantly, and the aboveground mother stems have withered and yellowed, at this time, the harvest must be stopped and transferred to autumn management. Autumn management, the focus is on the retention of asparagus autumn stems to accumulate nutrients and lay the foundation for the high yield of asparagus next year.
First, timely selection, breeding of mother stems, classification management
For asparagus plants transplanted in that year, each root disc retains 10 to 15 female stems (do not leave the garden, only cut weak and yellow branches); the number of retained mother stems for more than two years depends on the asparagus planting year and field growth. Field growth is robust and disease-free generally do not need to carry out secondary stem retention, just need to strengthen the management of plants and water and fertilizer, generally 2 to 3 years to leave 4 to 6 roots, more than 4 years 6 to 10 roots, the mother stem is required to be evenly distributed. Field plant diseases and insect pests are serious, especially stem blight is serious, and secondary stem retention is required, and autumn asparagus generally begins to retain the mother stem in September. The specific retention time is carried out in a good weather after the whole field shoots are unearthed and neatly excavated.
Second, thoroughly clear the garden and remove germs
For bamboo shoot fields that need to retain stems for the second time, after the asparagus harvest is over, it is necessary to clear the garden in time to keep the mother stems so as not to affect autumn hair. Generally around the beginning and middle of September, all the female stems on the ground are cut on sunny days, and transported out of the field together with weeds to burn or bury them in a place far from the asparagus field, and the soil around the root plate is peeled open and allowed to bask in the sun for 1 to 2 days. Then spray 40% asparagus green powder 600 times liquid plus 300ppm agricultural streptomycin, or spray 50% Raptor 600 times liquid or dixon 1 ~ 1.5 kg / mu or 45% Schnanin 300 times liquid, disinfect and sterilize the root disc and the surrounding soil, reduce the source base, in order to protect the growth of young stems from harm.
Third, reapply autumn fertilizer to promote stem growth
The heavy application of autumn hair rejuvenation fertilizer is conducive to promoting the vigorous development of autumn stems, expanding plant photosynthesis, accumulating more nutrients, and laying a material foundation for the next year's abundant production. Autumn fertilizer is mainly organic fertilizer, requiring more than 4000 kg of decomposing organic fertilizer per mu, adding compound fertilizer 25 kg or phosphate fertilizer 50 kg, potassium fertilizer 10 kg, urea 20 kg mixed application. At 20 to 30 cm from the root plate, ditch 15 to 20 cm, apply fertilizer deeply and cover the soil. After the mother stem is retained for one month, the topdressing is applied every 10 to 15 days, and 10 kg of urea is applied per mu. Starting in late September, extra-root fertilizer is applied once every 5 days before topdressing or 5 to 7 days after topdressing. Foliar fertilizers such as brassica are sprayed on asparagus stems and leaves in the evening or morning to strengthen the plant, prolong the green retention period and accumulate more nutrients.
Fourth, the whole branch is set up
Timely loosen the soil and weeds, before entering the rainy season, timely set up the whole branch to prevent the branches and leaves from collapsing to the ground, causing the small environment of the rhizome to be closed, remove the dead aboveground part in time, improve the ventilation and light transmission conditions, and raise the stem to prevent disease, so as to prevent the occurrence and spread of asparagus stem blight, brown spot disease and standing blight.
5. Prevention and control of pests and diseases
Disease: The most common disease of asparagus is stem blight. The anti-disease agents are: 30% Shuangji suspension 800 times liquid + 50% Shuangjisheng (former Luxin net) 500 times liquid + new high fat film; 30% Double Ji Sheng 800 times liquid + 50% Lu Feng 500 times liquid + high fat film; 50% Double Ji Sheng 500 times liquid + 80% Bidelide 800 times liquid + new high fat film. When spraying, the main stem 60 cm above the ground should be mainly sprayed, supplemented by the upper branches and leaves, and sprayed evenly.
Insect pests: The main pests that harm asparagus are: thrips, cotton aphids, grasshoppers, locusts, asparagus wood moths, lamp moths, night moths, bugs, armyworms, fourteen-point negative mud worms, inchworms, grubs, caddisflies, ground tigers, etc. It can be booby-trapped with insecticidal lamps and combined with spraying or root irrigation. It can be used with 15% kualaxing 1500~ 2000 times liquid or permethrin agents.
Asparagus is mainly exported to the international market, the residual poison of pesticides should be highly valued, and the use of high residue insecticides and organic arsenic fungicides is prohibited.