The propagation of roselle can be carried out by sowing, cutting, dividing plants or layering. In spring, sowing is usually done indoors in mid-April; Cuttings are usually carried out in the middle and late June, and semi-lignified top branches are used as cuttings, which are easy to survive; The division of plants should be carried out before germination in early spring; The layering propagation is best carried out in early and middle June, and the creeping branches at the lower part of the plant are pressed into the soil. Note that the branches buried in the soil must be cut through the cortex with a knife, so that they can produce callus and take root quickly, and then transplant them until they germinate in the early spring of the next year, and do not bury them before cutting the layering. 1. Cuttings are divided into hardwood cuttings and semi-lignified cuttings. When cutting hard branches, one-year-old mature branches are often cut into 15 ~ 20cm cuttings for cutting in the open field. Semi-lignified cuttings are carried out from June to July in summer, and semi-lignified top branches are used as cuttings, which is easy to survive. In order to improve the survival rate of cuttings, 500 mg/L indolebutyric acid (or other rooting powder, used according to the instructions) can be dipped quickly to promote rooting. Cutting can be carried out under a shady shed, in a greenhouse or in a full-light fog bed. It is best to disinfect the soil with phoxim in seedbed planting, which not only eliminates pests, but also has the function of sterilization and disease prevention.
2. Seeding propagation is generally used for a large number of seedlings. Broccoli seeds are small and difficult to harvest, so they should be harvested in time after the fruit ripens in June 5438+ 10, and the seeds should be harvested after dehydration and air drying. Sow indoor potted plants in the middle and late April of the following spring. Soak the seeds in cold water for 2-3 hours, then mix them into 2-3 times of plain sand, spread them in the leeward and sunny places to accelerate germination, and sow them after 6-7 days. Before sowing, water is poured on the soles of the feet, seeds and sand are scattered on the bed surface together, and after sowing, the soil is covered by about 0.5 cm, and then plastic film is added to keep the seedbed moist until the seedlings grow completely and retreat.
3. layering or ramet propagation should be carried out before the plants germinate in early spring. It is best to press the lower branches of plants into the soil during the growth period in the first half of June, and pay attention to the fact that the branches buried in the soil must cut the cortex with a knife to produce callus and promote its rapid rooting. Before germination in the early spring of the following year, cut off the unburied part before layering and transplant it. Rhododendron rubrum is a deciduous shrub, belonging to Caragana of Caprifoliaceae, with plant height 1.5-2m, crown width 1.5m, oval leaves, reddish shoots, grayish brown old branches, axillary cymes and terminal panicles, tubular funnel-shaped flowers, rouge red, flowering from late May to late September, high ornamental value and cold tolerance. From 2003 to 2005, we carried out the experiment of Red Prince Jin, and the results were summarized as follows: 1 materials and methods1./experimental materials In March 2003, the seedlings of Red Prince Jin were introduced from Shenyang, planted in the central nursery of the garden, ridged, and the row spacing was 50×50cm. 1.2 test method overwintering test: the overwintering test was conducted in 1 1 at the end of June, 2003, and * * was divided into four groups: a, cutting off the aboveground parts and covering them with grass 10cm and then covering them with soil10cm; B, cut off the overground part of the covered soil10cm; ; C, cut off the overground part10cm; Grass; D, keep the aboveground part motionless and let it overwinter naturally. In April of the following spring, open the cold-proof soil to check the wintering situation of the red prince brocade belt. 1.3 investigation on the resistance of red prince brocade in the cultivation experiment, the characteristics of high temperature resistance, drought resistance, saline-alkali resistance and pest resistance of red prince brocade in our area were investigated. Observe and record the biological characteristics and growth and development characteristics of Red Prince Brocade. Results and Analysis 2. 1 Analysis of meteorological factors of introduction place and origin First, the natural conditions of introduction place and introduction place were compared and analyzed (see table 1). As can be seen from the table, the latitude of Shihezi is higher than that of Shenyang, but the temperature, evaporation, sunshine hours and soil conditions in the two places are similar, except for the great difference in precipitation. The precipitation in Shenyang is three times that in our area, but our area is an irrigated agricultural area, which can meet the needs of plant growth artificially. 2.2 In early April, 2004, the overwintering experiment was carried out on the red prince brocade. The results showed that after covering soil or grass, A, B and C treatments, the foot buds remained green and appeared on the ground. Without cutting off the aboveground parts, the roots of plants that have been wintering in natural land have begun to sprout a small number of buds, but they do not show up; It shows that the red prince brocade belt has strong cold resistance and can safely overwinter on land in our region. 2.3 Multi-resistance investigation (1) of Red Prince Jin is drought-resistant and high-temperature-resistant. From July 20th, 2004, the temperature reached 42℃, which lasted for about a week. At the same time, without irrigation for a month, the leaves of the red prince brocade began to droop and become soft. After the temperature drops, water them once. Soon, the leaves of the red prince brocade returned to normal, from soft to hard. This is because the stomata in the lower epidermal cells of the leaves of the red prince brocade are closed, which reduces excessive water loss and has drought resistance and heat resistance. (2) Salt and alkali resistance. Part of the soil in the base has high salt content, and many shrubs and perennial flowers grow weakly. We planted some red prince ribbons here. After observation, the red prince brocade belt has been growing well. The Red Prince Brocade in my base was planted in Karamay. This area is hot, dry and short of water in summer, and the soil has high salt content. Conventional flowers such as Chinese rose are weak, while red prince brocade grows well, which shows that red prince brocade has strong salt and alkali resistance besides drought resistance and high temperature resistance. (3) Resistance to pests and diseases. There have been no pests and diseases since the planting of the red prince brocade belt, which shows that the variety has strong resistance to pests and diseases. 3. Growth and development characteristics of Red Prince Jin in Shihezi Through the test, the performance of Red Prince Jin in our region is stable and the plant grows well. However, due to the geographical differences between our region and the place of origin, the growth of Red Prince Brocade in our region is somewhat different from the place of origin. (1) Because the latitude of Shihezi is higher than that of Shenyang, the sunshine time in summer is longer than that of Shenyang, and the hot weather is later, so the flowering time in our area is a little later than that in the country of origin. (2) Because the farmland is irrigated all the year round, the plants in the red prince brocade have strong branching ability, the flower stems are larger than the origin, and the flowering period is longer than the origin, which lasts from the end of May to the end of September. (3) From the performance of three-year cultivation, the cultivation performance is stable, and the plant height and crown width are close to the origin. (4) After three years of cultivation, if the aboveground parts are not cut off in winter, the dead branches of the aboveground parts need to be cut off in the following spring, which grows slowly in the early stage and rapidly after July. Conclusion & Discussion: Red Prince Brocade is cultivated in our region, and can naturally overwinter in the open field when it snows in winter. Because of its own biological characteristics, it has the characteristics of drought resistance, cold resistance and lodging resistance. After investigation, it has good saline-alkali resistance and pest resistance. It grows well in our region, with stable cultivation form and beautiful colors. Planting once a year not only saves manpower and material resources, but also increases the varieties and colors of excellent perennial flowers in urban construction and landscaping, which is worth popularizing.