Experimental study on Industrial Rapid Propagation of Potato Test-tube plantlets

For many years, due to the self-breeding and self-breeding of farmers, the yield of potato decreased year by year, the quality became worse, the shape of the product became worse and so on. It has been proved by scientists that virus infection and its accumulation in potato blocks are the main reasons for potato "degradation". In order to solve the problem of serious degradation and yield reduction of the main potato varieties in our city, we took the virus-free production of potato as a key experimental subject, and carried out experimental research on the problems existing in virus-free production, so as to make use of resources. it reduces the production cost, provides a scientific theoretical basis for increasing production and income of potato, and effectively speeds up the modernization process of virus-free potato production in our city.

1 general situation of the test

1.1 the virus-free seedlings were provided by the Institute of vegetables and Flowers, Chinese Academy of Agricultural Sciences. The main varieties are Kexin 1 and Kexin 3, and a small number of varieties are introduced, such as Kexin 13, Bashu 9, Bashu 10, as well as Feirita, Atlantic and so on.

1.2 the test site is located in the plant tissue culture and factory seedling workshop of the Municipal Institute of Agricultural Sciences, which is equipped with air conditioning and can adjust the change of temperature.

1.3 the virus-free seedlings were purchased in March 2004. After the laboratory instruments were bought back in May, they began to expand in small quantities, and mass production was carried out at the end of July.

2 test method

The technological process of the experimental production is as follows: medium configuration-bottling-sterilization-transfer-culture.

2.1The MS medium for potato test-tube plantlets is characterized by high concentration of inorganic salts and ions, and is a stable ion balance solution. The quantity and proportion of nutrients can meet the nutritional and physiological needs of plant cells. (1) MS medium formula: including a large number of elements, trace elements, iron salts, organic matter, others (Agar, sugar, sterilized water); (2) preparation of mother liquor: in order to make all kinds of ingredients convenient and accurate, reduce errors and cumbersome, various reagents are generally expanded 100 times, weighed and prepared into mother liquor, spare. Each time when preparing the medium, it is only necessary to take the mother liquid 10ml/L to make the medium. (3) pH regulation of culture medium: after all kinds of ingredients were prepared, the pH value was measured by pH test paper or pH instrument. The pH required for potato test-tube plantlets was 5.8-6, and then Agar was heated to completely dissolve.

2.2 bottling the medium into a 7 × 7 × 10cm cuboid four-spin colorless glass bottle, be careful not to adhere the medium to the mouth of the culture bottle, generally the amount of medium should be able to lift each stem segment, and seal with a breathable sealing film.

2.3The autoclave was used for sterilization, the temperature was controlled at 121℃ (plus or minus error of 1 ℃), and the time was set at 1820 minutes. After sterilization, slowly deflate to normal pressure, or cool naturally, open the lid of the pot and put the sterilized culture bottle on the worktable for cooling.

2.4 the transfer is carried out on the ultra-clean worktable in the inoculation room, the transfer material is the imported virus-free original species, and the transfer tools are scissors, tweezers, alcohol lamp, 75% alcohol, etc., in full accordance with the aseptic operation procedure. During the transfer, the seedling material was first cut into a stem segment with 1 or 2 axillary buds, and the stem segment was inserted vertically into the culture medium in the sterilized flask according to the original up and down direction of the plant (which must be distinguished). Note that the bud eye part of the leaf base can not be inserted into the culture medium. Each bottle can be evenly inserted into 15-25 new stem segments, of which 20 are the best, which is beneficial to the space utilization of the bottle and the growth of seedlings. After the bottle is inserted, it is sealed with the original sealing film, and the variety name, transfer date, transfer person, etc., are marked, and the original files are recorded in the file record book.

The necessary conditions for culture are as follows: the temperature is generally 20: 25 ℃, fluorescent lamp is used as light source, and two 40w fluorescent lamps are installed on each layer at the 30cm from the shelf surface, which can reach the light intensity of 2000lx and basically meet the growth needs of potato virus-free seedlings.

3Test conclusion and analysis

It was observed that under the condition of 18-20 ℃, 2000lx light and airtight asepsis, the terminal buds began to grow in 2 days, rooting began in 3 days, and grew to 5 leaves in 22 days and 25 days, and the plant could be grown at the height of 6~7cm. After the stem segment was transferred, it began to grow in 3 days, began to take root in 5 days, and became a plant in 25-30 days. And at 18-20 ℃, the strong leaves of the seedlings were large. At about 25 ℃, it usually begins to germinate in 2 days, root in 3 days, and grow up in 20 days. The seedlings are thin and the leaves are small. At 28-30 ℃, the buds began to take root one day after transfer, with few roots, difficult to form seedlings and many deformities. Stem thickened, terminal bud necrotic, leafless, fibrous root. Conclusion: the seedling rate is high when the test-tube plantlets are cultured at about 20 ℃.

3.2 pollution according to statistical analysis, in the early stage of test-tube seedling production and winter production, the pollution rate is about 4.4%-5.7%, while in the mid-August-September high temperature season, the pollution rate is increased to about 15%, and most of them are bacterial pollution. The conclusion is that the production period of potato test-tube plantlets should avoid the high temperature season.