Seedling raising technique of softwood cuttings of European spruce

European spruce is an excellent tree species introduced from northern Europe in China. The tree grows fast. Because of its straight stem shape, wide adaptability, especially strong cold resistance, it has become not only an excellent timber tree species, but also an ornamental tree species for urban greening because of its beautiful tree shape and dense evergreen branches. Due to the direct introduction of seeds, the seedling growth is slow, it takes 5 years to get out of the nursery, and a large amount of foreign exchange is needed to introduce seeds, so the development is very slow. In order to speed up the promotion of this tree species and meet the needs of the rapid development of forestry construction and urban and rural greening, we carried out the experiment of raising seedlings with tender wood cuttings. the results showed that the rooting rate was 77.5%, the average number of roots per plant was 5.6, and the preservation rate of transplanted seedlings was 85%. Cutting seedlings can not only maintain the excellent characteristics of the mother tree, but also make the seedlings out of the nursery two years ahead of schedule.

I. ear wood collection

In the stand under 10 years old, the excellent mother tree with straight trunk and thick honey crown was selected, and the semi-lignified twigs of the same year were collected as ear wood. The spike wood is required to grow healthily, free from diseases and insect pests and without mechanical wounds. The time of ear picking is best to be planted with picking. If the cutting site of the cuttage forest is far away, it can be collected 2 days before cutting, but in the process of transportation, attention must be paid to keeping water, and the base can be soaked with high concentration hygroscopic agent to retain water.

Second, the setting of slotting machine

The slotting machine adopts cantilever rotating all-optical automatic spraying device. The slotting bed is located near the source of water in the nursery. According to the requirements of the spraying device, a circular slotting bed with a diameter of 13 meters and a height of 50 centimeters is built. The periphery is made of brick and cement, and the base leaves holes for drainage every 1.5 meters. First lay a layer of 15ml 20cm thick pebbles on the bed, cover it with a filter layer of pebbles about 10cm thick, and then cover the filter layer with 20cm thick pure river sand for soil insertion.

Third, insert bed sterilization

In order to prevent cuttings from being harmed by fungi and bacteria and affect rooting and survival, soil cutting must be sterilized before insertion. First fully rinse the bed with clean water, and then spray with 0.5% potassium permanganate solution, the dosage is 2500m3 / m2, or you can spray it with 500 times carbendazim.

4. Cutting and cutting

The cutting time is about June 20. The spike wood of European spruce was cut into 10 × 12 cm long cuttings with terminal buds, and the thin, withered and stunted branches were removed. In order to improve the survival rate of cuttings, after cutting, every 50 cuttings were soaked in 3cm indole butyric acid solution with the concentration of 1000ppm for 30 minutes. The cuttings were cut before 10:00 in the morning and after 4 p.m., with a cutting depth of 3.5cm and a row spacing of 3 × 5cm (666 roots per square meter), followed by watering, so that the cuttings were closely combined with soil.

Fifth, plug-in management

1. Sterilization and disease prevention. Insert all the beds together, immediately spray 500x carbendazim solution for sterilization, the dosage is 1000 ml per square meter. From now on, take the medicine every 10 days, and spray it again after the rain. After the spray stops in the evening of spraying time.

2. Water management. Water management is the key to the survival of cuttings. if the automatic intermittent spraying system is started after cutting, the spraying interval time and spraying time must be strictly controlled. The appropriate time for each spray is to rotate the arm for 2 weeks. Interval time, the first 20 days after insertion, from 10:00 to 5 pm on sunny days, spray every 2 mi 3 minutes, and reduce the spray time before and after 10:00 every 10 mi 15 minutes. After 60 days and 60 days, the times of spray were correspondingly reduced to 7 minutes, 30 minutes, 15 minutes and 60 minutes every 6 min, 20 mi, 15 min and 40 min, respectively. The number of spraying should be reduced on cloudy days and should not be sprayed at night.

3. Extra-root fertilization. Fertilization can supplement nutrients to cuttings and improve the survival of cuttings. From 20 days after insertion to late September, 0.2% urea and 0.3% potassium dihydrogen phosphate mixture was sprayed every 10 days, with a liquid volume of 0.5 kg per square meter. External fertilization was carried out after stopping spraying in the evening.

Transplanting and changing beds

In order to accelerate the growth of seedlings, the one-year-old seedlings survived by cuttings must be transplanted to the general nursery for 2 years. For example, in late June, the survival seedlings should be raised on the cuttage bed at the end of October, the seedlings with poor root system should be removed, and the seedlings would be bundled up according to 60 plants, and then Sha Zangyue would be carried out. In the following spring, double ridges were used for transplanting. The ridge distance was watered immediately, and other management measures at seedling stage were the same as those of field seedlings.