Study on the Technology of Protecting Seedlings of Ural Licorice with Plastic Film Mulching in Different Sowing Times
Zhou Chengming1 Luo Xiaoling2 Wan Yuling2 Zhen Shilong3 Li Gang3
1. Beijing Daxing Shizhen Institute of Chinese Herbal Technology (Beijing 102609)
2. College of Chinese Materia Medica, Jilin Agricultural University (Changchun 130118)
3. Jilin Specialty College (Jilin 132109)
[Abstract] In order to improve the direct seedling rate of Ural licorice seedlings, this experiment uses four plot experiments with repeated treatments at different sowing dates. As a result, the emergence rates of mulch covered with four different sowing dates were significantly higher than the control bare sowing area planted in the same period. Improved, the seedling rate is also significantly improved, the emergence time is about 10 days in advance, the best mulch cover sowing date is early April, northern areas in early spring, there are multiple sand storms and cold spring, mulch cover technology can improve ground temperature, protect the soil, effectively avoid sand storms Invasion of licorice seedlings.
[Keywords] Glycyrrhiza uralensis film mulching technology Glycyrrhiza uralensis Fisch is a perennial herb belonging to the genus Glycyrrhiza, which is used as medicine in underground roots and rhizomes. It is the most important commonly used Chinese herbal medicine in China . In northern arid and semi-arid soils, domestic wild Ural licorice varieties have been studied by many people [2, 3, 4, 5]. Due to the poor soil retention and thermal insulation in early spring in the north, it is accompanied by multiple sandstorms and cold currents in early spring. Invasion often results in a low germination rate and seedling rate of licorice cultivation, which affects yield and quality. In this experiment, experimental plots were set up in the Yongding River Basin in Beijing. Film mulching technology was used to protect the loquat, keep warm, and prevent dust storms in order to increase the emergence rate and The rate of seedling formation reduces the wind test of licorice planting and improves economic benefits.
1. Experimental conditions and methods.
1.1 Experimental conditions
1.1.1 The soil for the test is located in Wangchu Village, Dodian Town, Fangshan District, Beijing. It belongs to the alluvial plain of the Yongding River, with sandy soil, surface sandy soil, organic matter 0.82%-0.90%, total nitrogen 0.028%-0.065%, alkaline hydrolysis Nitrogen 39.50-49.32 × 10-6μg.g-1, P2O5 12.87-14.24 × 10-6μg.g-1, K2O 53.2-96.3 × 10-6μg.g-1, pH 7.9 -8.3, the soil layer is deep, but the water and fertilizer retention properties are average.
1.1.2 Climate Fangshan District in the southwestern suburbs of Beijing is a warm temperate and semi-arid monsoon climate zone. It has less rain and wind in spring, hot and rainy summer, cool and dry autumn, cold and dry winter, and annual rainfall of 568mm. The amount is 63% of the whole year, and the rainfall intensity is large, and the soil water retention is poor.
1.1.3 The tested seeds were wild Ural licorice seeds (G.uralensis) collected in Inner Mongolia, treated with chemical drugs and coated, 90,126 seeds per kilogram, with a germination rate of 91%, a purity of 100%, and a purity of 97%.
1.1.4 The test mulch is a standard agricultural disposable mulch with a thickness of 0.008mm and a width of 1.5m.
1.2. Experimental methods
1.2.1 Experimental method The design of the test plot area is 3 × 5m2, and the seeding amount per plot is 90g. From March 30 to April 17, every 6 days is a sowing period. Depending on the temperature in the membrane, three repetitions were set for each treatment, and the control was naked sowing. Observe the indicators of the seedling stage of the covered film area and the naked sowing area, and finally calculate the seedling rate. See photo (1,2).
1.2.2 Seeding method For seeding, firstly rake the ground flat and fine, dig the ditch with a ditch opener, 8 rows per plot, and spread the seeds at 90g / plot evenly in the trench, cover the soil, and steadily, then cover the treatment area. Membrane, the control is the naked sowing area, without covering the membrane.
1.2.3 Collection of experimental data The temperature of 5cm underground and the temperature of the air inside the film in the cover film area is measured with a mercury thermometer, measuring three temperatures early, middle and late, recording and drawing the temperature change chart. The emergence rate and the emergence rate are both determined by random sampling. In this experiment, the length of the seedling rows was 74 cm. Two rows were measured each time to calculate the average. The length of the young roots at the three true leaf stages was also a random sampling method. 50 seedlings were dug out and measured separately, and the naked seedlings planted in the same period were also measured at the same time.
2. Results and analysis
2.1 The temperature change curves at different times of 5cm underground and 5cm below the bare sowing area are shown in Figure (1,2,3) and the temperature changes at different times in the film are shown in Figure (4). The results showed that: ① The temperature of 5cm underground in the covered film area was significantly higher than that without the covered film, and was stable, especially in the early spring cold currents and sand storms, which could effectively increase the ground temperature and protect the normal growth of licorice seedlings. ② After covering the membrane, the temperature inside the membrane is obviously higher than the normal temperature. ③ The surface of the membrane is full of water droplets, and the water droplets drip back into the soil.
2.2 The licorice planted in stages, no matter which period of licorice seed is planted, the mulch is covered about 10 days earlier than the germination and emergence of the bare sowing area, and the emergence is neat and consistent, and the emergence rate of the bare sowing area is low, especially the sowing on April 5. Most of the seeds in the bare sowing area died of drought and cold spring. The field observations of the emergence rate are shown in Table 1. The results showed that in the emergence rate, the cover film area was significantly higher than the bare sowing area. For example, the emergence rate of two cotyledons in the licorice-covered area planted on April 5 was 33.09%, and the control area was only 1%. See photo (3, 4).
2.3 When the seedlings in the film-covered area reached three true leaves, we randomly took 50 seedling roots in each plot to measure the length of the seedlings compared with the control area sowed at the same time. The recorded results are shown in Table 2. The results showed that when the seedlings in the cover film area had grown into 3 true leaves, the leaves were shiny dark green, while in the bare sowing area there were only 1-2 true leaves, and the root length was significantly different. The shoots in the cover film area were as long as 15 cm. The young roots in the bare sowing area are only about 9 cm long.
3.1 From this experiment, it can be seen that the technology of licorice seed sowing and mulching can significantly improve the seed emergence and seedling rate, which is very beneficial for planting licorice on sandy loam soil in early spring in the northern region, especially in early spring and cold in spring and irregular March-April. During multiple sandstorms, the use of mulch mulching technology can increase the ground temperature and the temperature inside the film, and can protect it, which can effectively avoid the catastrophic damage of licorice.
3.2 Among the four different sowing dates in this experiment, it was better to plant the cover film on April 5. Not only the seedling rate was high when 2 cotyledons were used, but the highest seedling rate was obtained when 3 true leaves were used. Therefore, it is advisable to plant seeds and cover films in large areas in early April, which provides a scientific basis for planting licorice in northern areas, especially in the northwest, to improve yield and quality.
1. Zhou Chengming, Kong Xiangfei, Ma Yishu, Wang Fengqi Research on Cultivation Technology of Ural Glycyrrhiza uralensis in Daxing District of Beijing, China Journal of Chinese Materia Medica, 2000, 25 (3): 140--143
2. Zhou Chengming's Cultivation of 80 Commonly Used Chinese Herbal Medicines, Beijing China Agricultural Press, First Edition, 1998.1
3. Zhou Chengming's Cultivation of 80 Common Chinese Herbal Medicines, Beijing China Agricultural Press, Second Edition, 2002.4
4. Zhao Yangjing, Chen Zhen, Li Xianen, and the suitable sowing date of licorice introduced in the semi-arid area of Huanghuaihai, China Journal of Chinese Materia Medica, 1999, 24 (4): 208
5. Fu Kezhi and other licorice wild plants in China, Harbin, Northeast Forestry University Press, 1989.2
A study on enhancing seedling number which adopt the technique of covering seed with plastic film in different sowing period
(BeiJing shizhen institute of Traditional chinese medicines, BeiJing, 102609)
Luo Xiaoling Wan Yuling Yin Chunmei Wang Xiuquan
(JiLin Agricultural university, ChangChun, 130118)
[Abstract] In order to enhance the number of uraler licorice seedling in fields, the experiment adopt small plot trial method that sow seeds in four different time. And on study the seedling number of the trials adopting the technique which cover seeds with plastic film is notably higher than seedling number of ck trial every stage. The time of seed grown to seedling is advanced about ten days also. The best time of sowing uraler licorice seeds is on April 5 in Bei Jing.
[key word] Glycyrrhiza uralensis cultivation; The technique of covering seeds with plastic film; The technique for ensuring seedling number
Table 1 Observation results of 2 cotyledon emergence rates in 4 different sowing dates from March 30 to April 17
Determining the average number of bare sowing areas in the cover film area during the sowing period. Determining the average emergence of the day-bare sowing areas (month-day). Period (month-day). Emergence rate (%). Period (month-day). Seedling rate (%).
3 30 4 13 27.45 4 13 13.78
4 5 4 18 33.09 4 18 1.00
4 11 4 20 21.82 4 26 10.92
4 17 4 26 21.49 5 5 18.30
Note: The licorice seedlings in all naked sowing areas emerged about 10 days later than the cover film area. Most of the seeds died in the naked sowing areas due to drought on April 5.
Table 2 Film-covered licorice planting rate and average young root length in 3 true leaf stages at different sowing dates
Sowing date (month and day) Date of measurement of various indicators in the cover film area and naked sowing area (month and day) 3 true leaf seedling growth rate in the cover film area (%) Average root length (cm) in the cover film area 2 pieces in the bare sowing area True leaf seedling growth rate (%) Mean young root length of control naked sowing area (cm)
3 30 5 3 25.16 15.13 12.85 9.1
4 5 5 8
1 The temperature change line between the mulching area and the bare sowing area at 5cm underground at 8:00 am, the solid line is the temperature of the mulching area, and the dotted line is the bare sowing
Figure 2 The temperature change line of the ground temperature in the film and 5cm below the naked sowing area at 12:00 noon. The solid line is the temperature of the ground in the film.
Figure 3 The temperature change line at 5cm underground between the covered and uncoated areas at 10:00 pm. The solid line is the underground temperature of the film area, and the dotted line is the underground temperature of the bare sowing area.
Figure 4 Temperature changes in the film at 8:00 am, 12:00 noon, and 10:00 pm.