Propagation method of Robinia pseudoacacia (basic knowledge): Optimal propagation time: It is most suitable to sow Robinia pseudoacacia before and after the "Grain Rain" solar term.
Best growing soil: Robinia pseudoacacia likes loam, sandy loam, sandy loam or clay loam with deep, fertile, loose and moist soil.
Growth humidity requirements: Robinia pseudoacacia likes humidity and grows fast in coastal areas with high air humidity.
Optimum growth temperature: Robinia pseudoacacia likes warm environment and is a temperate tree species.
Optimum growth light: Robinia pseudoacacia likes light and is not tolerant to shade.
Matters needing attention in Robinia pseudoacacia breeding: fertilization;
After Robinia pseudoacacia seedlings, 1 topdressing 1 irrigation, urea 45 ~ 75 kg/hm 2. At the end of June, combined with irrigation, topdressing was divided into two times, and the fertilization amount was 75 ~ 195 kg/hm 2, and fertilization was stopped at the beginning of August. It is best to plow in winter and rake the ground in early spring, and apply 3000 kg to 5000 kg of decomposed base fertilizer per mu. Soil preparation should be done early in spring, with deep ploughing (above 25 cm), fine raking and leveling. At the same time of soil preparation, mix 5 {BF} phoxim (1 kg) and 1 kg black alum (ferrous sulfate) powder per mu, then mix 40 times of fine soil and sprinkle it into the soil for soil disinfection.
Water supply point:
Robinia pseudoacacia is very sensitive to water conditions, and grows slowly in places with too high groundwater level and too much water, which is easy to induce diseases, leading to rotten roots, dead branches and even death of plants.
Pruning points:
1) Pruning: The time and quantity of pruning depends on the purpose of afforestation. General afforestation should be pruned after the young forest is closed; In order to cultivate tall trunks and prevent excessive shading, the surrounding green spaces and shelterbelts should be trimmed properly in the first three years. Robinia pseudoacacia under 2 years old has a lower trunk. Generally, strong and upright branches are selected as the trunk, and the rest branches are drained according to different conditions. After the trunk is pruned to a certain height according to the ratio of crown to stem, the thick competitive branches, overgrown branches, upright branches and some over-dense side branches, drooping branches and dead branches in the upper part of the crown are drained.
2) Pruning sprouting strips: after pruning, the long branches on the trunk or main side branches should be removed or cut off; For sparse branches at the base of trunk and the top of trunk heading in winter, sprouted new buds and buds should be cut off as soon as possible. Pruning should be carried out in summer, preferably from early June to early July, which has the advantages of less trauma and quick healing, and generally does not sprout a large number of branches, which is beneficial to the growth of young trees.
Breeding point:
Robinia pseudoacacia is usually propagated by sowing.
sow seeds
Robinia pseudoacacia is vulnerable to late frost and freezing injury when sowing in drought, so sowing should be done later rather than earlier, especially before and after Grain Rain Festival. [5] Border sowing or field sowing can be used. Generally, field-type seedling raising is adopted. Leveling the Miao Di first, then ditching and drilling, the row spacing is 30~40cm, the ditch depth is 1.0~ 1.5cm, the bottom of the ditch should be flat and the depth should be consistent. Seeds should be evenly sown in the furrow, and then covered with 1~2cm thick soil in time, and gently suppressed, from sowing to emergence.
seed treatment
Robinia pseudoacacia pods changed from green to reddish brown, and the pods were hard, dry and mature. Seeds should be collected in time, and the peel, grain and contents should be removed by sun exposure to obtain pure seeds. Pod seed rate 10 ~ 20 {BF}, 1000-grain weight about 20g, germination rate 80 ~ 90 {BF}.
The seed coat of Sophora japonica is thick and hard. Germination must be accelerated before sowing, that is, the seeds are poured into hot water at 60~80℃, fully stirred with wooden sticks, and mixed with cold water for 5~ 10min, and the water temperature is reduced to 30~40℃. Then remove the impurities and bad seeds floating on it, soak the good seeds for 24 hours, and then remove the hard seeds with a fine-mesh iron sieve when they are slightly dry. After 4 ~ 5 days, the seeds germinate and can be planted.
Pest control:
Robinia pseudoacacia is endangered by many kinds of pests, such as termites, leafhoppers, scale insects, locust aphids, scarabs, longicorn beetles, locust foot moths, mulberry-winged foot moths, smelly bedbugs and so on.
Robinia pseudoacacia seed wasp is the main pest of seeds, and the damage rate can reach 80 {BF}. The pests and diseases of Robinia pseudoacacia seedlings include ground maggots, weevils, aphids, damping-off and so on. It was found that spraying 40 {BF} omethoate emulsion 1500 times can control pests. For damping-off disease, 300-400 times of 50 {BF} mancozeb solution should be sprayed at the initial stage of the disease to sterilize and protect seedlings.
Expanding knowledge-the function of Robinia pseudoacacia: 1, the use value
Robinia pseudoacacia is hard and heavy, resistant to corrosion and wear, and suitable for sleepers, vehicles, buildings, columns and other materials. It is a fast-growing firewood forest tree species with fast growth and strong germination; It is also an excellent nectar source plant.
Robinia pseudoacacia is an important fast-growing timber tree species with fast growth, tough wood, fine texture, elasticity, water resistance and corrosion resistance. Can be used as materials for buildings, sleepers, vehicles and farm tools; Leaves contain crude protein and can be used as feed; Flowers are excellent nectar plants, and the seeds are pressed with oil as raw materials for soap and paint.
2. Industrial value
Robinia pseudoacacia in food industry, locust bean gum is often compounded with other edible gums to be used as thickener, water-retaining agent, adhesive and gelling agent. Elastic jelly can be formed by compounding it with carrageenan, while brittle jelly can only be obtained by using carrageenan alone. When it is compounded with agar, the breaking strength of gel can be significantly improved. When compounded with seaweed gum and potassium chloride, it is widely used as a composite gelling agent for canned food. The combination of carrageenan and CMC is a good ice cream stabilizer. It can also be used as a water-retaining agent in dairy products and frozen dairy candy to improve taste and prevent the formation of ice crystals.