How to thresh astragalus seeds?

1 Sulfuric acid rot skin treatment method:

Treatment of astragalus seeds with sulfuric acid is a traditional and effective method, according to the degree of hardness of the seed coat enamel layer, 50% to 80% sulfuric acid solution can be used, soaking time can be adjusted in 3 to 5 minutes. According to our experimental data, the best sulfuric acid concentration and soaking time relationship is: 65% sulfuric acid solution soaked astragalus seeds 4 minutes the best results, too short a period of time can not destroy the seed coat enamel layer, too long a period of time will destroy the seed internal germ. Sulfuric acid treatment of seeds immediately after rinsing with water, generally under running water after rinsing 5 to 6 times, with 1% to 2% sodium bicarbonate solution soaked for 2 to 5 hours, so that it is slightly alkaline, in order to facilitate seed germination.

Corrosion standards: sulfuric acid and astragalus seeds must be mixed evenly, and the removal of the surface enamel layer of the color of the seeds is a deep burnt yellow.

The advantages of sulfuric acid corrosion method are: fast, effective, germination rate of up to 90% or more, easy to promote the application. The disadvantage is: the use must be careful to avoid being burned by concentrated sulfuric acid.

2 Mechanical skin treatment method:

2.1 Rice milling machine grinding method: the use of rice milling machine milling wheel rotating at high speed to bruise the enamel layer of the seed. The number of times for 1 to 2 times is appropriate. This method is simple, low cost, high efficiency. The intensity and frequency of seed milling should be based on the model of rice milling machine and astragalus varieties, humidity, maturity and other specific circumstances.

2.2 Stone milling method: the principle of the same rice milling machine, the number of stone milling for about 70 laps, the side of the pressure turned, so that the seed milling uniformity, generally in the stone milling on the seed should be thicker, so as to avoid the seed was crushed.

2.3 Sanding method: fine sand mixed with seeds 2:1 ~ 4:1, placed in the mortar and evenly ground, has reached the purpose of breaking the enamel layer.

2.4 stone grinding, sand grinding combined method: sand and seed ratio of 2:1 ~ 1:1, evenly mixed and spread on the stone grinding, abrasion of the seed coat, you can take the sand under the seed.

Grinding standards: mechanical broken skin, the seed coat enamel layer burrs, the surface loses its luster, the color of the seed coat from brownish-black to grayish-brown or earthy-yellow, but do not make the seed grinding excessively and damage the seed kernel, you can take the sand under the seed.

The advantages of mechanical skin-breaking method are: time and labor-saving, sample processing flow is high, can be applied to mass production. Disadvantages are:The technology is not easy to master, grinding excessive will lead to seed breakage, affecting the germination rate.

3 Changing water temperature seed soaking method:

3.1 Method 1:Selected Astragalus seeds during the day immersed in water at about 35 ℃, cold water at night immersion, repeated treatment for 4 to 5 days (when the Astragalus seed glaze layer can be stopped when the softening of the seed), with a wet cloth to cover the seeds to promote germination, 2 days after the seeds have a tendency to germinate can be sown. This method of treatment of seedling emergence rate is greater than 75%, seedlings neat, but more time-consuming and laborious.

3.2 Method 2: soak astragalus seeds in water at about 50 ℃, after 9 to 12 hours, room temperature germination, the rest of the steps with the same method. The seedling rate of this method is basically the same as method one, but the germination potential is not good.

3.3 Method 3: soak the seeds in water at about 100 ℃, and quickly and evenly stirred for 1 to 2 minutes, immediately adjust the water temperature to 40 ℃, and then soak for 2 to 3 hours, and then pour off the warm water, cover the seeds with a wet cloth to germinate, and when the seeds sprout can be sown.

The advantage of the method of changing the water temperature for seed soaking is: the conditions required are simple and feasible. Disadvantages are: the program is more cumbersome, the water temperature and time must be strictly controlled, too short a time to achieve the effect of skin-breaking, too long a time to gradually reduce its germination rate.

4 drug seed dipping, seed mixing method:

4.1 Alcohol ether seed dipping: use 25% ~ 35% ethylene glycol ether, ethylene glycol butyl ether and other infiltration treatment of astragalus seeds for about 24 hours, which can significantly improve the germination rate, and can promote the growth of germ, embryonic root growth;

4.2 Hormonal seed dipping: use 200mg / Kg erythromycin solution to dip the seeds for 24 hours, can improve the seedling rate, but the concentration is too high. Seedling rate, but the concentration is too high will inhibit germination, and lead to seedling rot;

4.3 plant growth regulator seed dipping: 50 to 200mg / Kg rooting powder can promote rooting, to achieve the effect of seedling strength;

4.4 drug seed mixing: 0.3% to 0.5% carbendazim, 1 ‰ trichlorfon, 2% octopenthos powder mixing seed with prevention of diseases and pests effect.

The advantages of drug seed dipping and seed mixing are: it can promote seed rooting and germination and control of pests and diseases. The disadvantage is: the concentration of drugs is not easy to grasp, the concentration is too low effect is not good, the concentration is too high easy to cause drug poisoning.

5 Summary and Discussion

The above four treatments have their own advantages and disadvantages, if used alone, the germination rate from high to low order: "sulfuric acid skin treatment method" ≥ "mechanical skin treatment method"﹥ "Change the water temperature soaking method" ﹥ "drug soaking, seed mixing method". In actual production, each method can be used in combination, the principle is:

(1) "drug seed dipping, seed mixing method" is generally used with the first three methods;

(2) "sulfuric acid skin treatment method" should not be used with the "mechanical skin-breaking method". "Mechanical skin-breaking treatment", "change the water temperature soaking method" used in combination, so as not to damage the seed germ;

(3) "sulfuric acid skin treatment" can be used alone, or after the sulfuric acid treatment of the seed. After the sulfuric acid treatment of seeds, can also be selectively adopted "drug seed dipping, seed mixing method";

(4) "Mechanical skin-breaking treatment method" combined with the use of "changing the water temperature soaking method", before sowing the seeds, the use of a combination of "water temperature soaking method".