What is a spawn?
If we talk about the fruits and vegetables, they can be grown by the means of seeds and roots. It is a fungus and hence cannot be grown by means of roots or seeds. For its germination spores are used. In the ancient age these spores were used for the germination of the mushroom. But in this generation they are using an advanced technology in order to make the mushroom seeds. They prepared it through culture media and is termed as a spawn or the mother spawn.
Nowadays most of the people are using the process of tissue culture in order to prepare the seeds for the cultivation of mushrooms. For the tissue culture the portion between the cap and root i.e. the stem is taken the mycelium inside the stem is transferred to the media. The chemicals used for the preparation of the media depends on the type of mushroom. For example, in case of an oyster mushroom, P.D.A (Potato Dextrose Agar) is used whereas In case of a button mushroom C.E.A(Compost Extract Agar) is used. Also some of them like M.E.A(Malt Extract Agar) also can be used depending upon the type of a mushroom. The mycelium is transferred to the media and is kept in an incubator at around 25°C. The mushrooms does not grow better from every culture so we have to select only the better cultures during the preparation of spawn. A pure culture tube can be multiplied into many culture tubes.
In order to germinate a very good mushroom it is very necessary to make a very good spawn,and hence should be prepared scientifically. So the things to be noted while making a spawn are as follows.
1. Lab
2. Experienced person in the field
3. Machinery equipments like Laminar flow, Autoclave, Incubator, Refrigerator etc.
4. Chemicals
In exception to this the vegetative mycelium should be pure and fresh. In order to grow a pure culture we should prepare a media which has huge amount of nutritive elements used for the development of fungus.
The preparation of a media
1. PDA(Potato Dextrose Agar)
Peeled potato :200gm
Dextrose :20gm
Agar agar powder :20gm
Pure water :1000ml
2. CEA(Compost Extract Agar)
Compost :200gm
Dextrose :20gm
Agar agar powder :20gm
Pure water :2000ml
3. MEA(Malt Extract Agar)
Malt :20gm
Agar agar :15gm
Pure water :500ml
1. PDA
In order to prepare a PDA first of all we have to take a peeled potato, wash it and cut into small pieces. In a vessel containing water of 1000 ml, boil the potato for 30 minutes. After it is converted to soft and white potato, filter it so that the peeled potato is separated from water. Now you can throw the potato an put the water. Now add 1000ml of distilled water and heat it in a clean vessel. After it is heated put the weighted amount of dextrose and agar agar powder and shake it from time to time.
After few time fil1 that liquid 1/3rd of the test tube and make it non-absorbent by keeping a cloth at the top of it. Wrap it with an aluminium foil and after all the liquid is filed , put the test tubes inside the autoclave for sterilization at around the temperature of of 120°C around 30-45 min. Make sure that it is sterilised completely inside the autoclave otherwise there may be the problems of germs later on. After, the test tubes are kept in inclined position. You can find tomorrow that the liquid remains in the form of a fungus which is ready for culture in the tube. This can be stored for a long period of time as well.
2.CEA
In order to prepare a CEA instead of peeled potato as in the above process, the compost is used and follow the same instructions as above for PDA.
3.MEA
Take the required materials as mentioned above and follow the instructions as in PDA.
Storage of a culture.
The culture of the mushroom spawn can be stored in different ways for a long period like 1-2 years. But must be transferred to a new media in every three months of period. Also make sure that the temperature during the storage of the culture is approx. 20°C. Also it is very essential to protect it from the insects otherwise there may be the probability of getting a lots of disease.
Substrates during the preparation of spawn.
For the preparation of the mushroom spawn, it is considered that wheat seeds are the best substrates among all the agricultural products. This is because mushroom has neither a leaf, nor a stem and not a root as well. That is why it cannot manufacture its own food for its growth. In whatever substratum it grows, it absorbs the minerals from the same substratum. And that’s why the wheat seeds has a huge amount of protein starch required for its growth. This helps to expand fungus in wheat as well as for the germination as well.
The mushroom has a vital role to get success in the production of a mushroom. Depending upon the type of a mushroom the spawns are available on different substrates. For example in case of an oyster mushroom wheat is used and etc. It is said that the best substrates for the spawn is sorghum, since it is not found all over the countries, wheat seeds are taken as a common.
Procedure
First of al1 we have to do a selection of wheat seeds, and during the selection we have to select the best seeds, like the one which do not have insects, dusts etc. and always the whole seeds. Make it clean and tidy. After it is cleaned boil the clean water in an aluminium container and put the wheat seeds for about 10-15 minutes. Shake it well while boiling. While shaking throw the wheat floating above water. Make sure that while boiling the wheat seeds, they do not break which may cause a damage in the spawn. After boiling it should be filtered and the boiled wheat should be dried and kept in air for 30-45 minutes. It should be dry though it is cooled. Now once it is dry and cooled, add calcium carbonate and gypsum is mixed at the ratio of 6:12. Now it is shake well and then packed in a clean bottle at the approx. weight of 250gm. Now the bottle is made tight with cloth and aluminium foil. After the bottles are sterilized in an autoclave for 2-3 hours at around 100°C. After it is removed from autoclave it is then made cold and the next day kept for incubation with laminar flow. The room should be made clean day by day, a spray with formaldehyde can be used. It is kept in an incubation room for about 3 weeks at 25°C.
Now this is called the mother spawn. The spawns are created from these mother spawn. In order to make spawns, a little mother spawn is kept in a bottle of a boiled wheat’s under a laminar flow for three weeks at around the temperature of 25°C. Now the bottle is filled with lots of fungus and is ready for cultivation. It can be made in a plastic bags instead of a bottle but the plastic should lie in the group of pp.
Storage:
An ordinary spawn cannot be stored for a long period of time, it should be consumed as soon as possible. In order to store a culture it should be kept at a very low temperature i.e. 0°C to -10°C at a maximum period of six months. A well done spawn can be stored in a temperature of 12°C to 14°C for a maximum period of two months. During the process of production, the spawn can be used for around 4 days at the room temperature.
Thing to be noted while the preparation of spawn:
Lab should made in a scientific way.
The lab should be cleaned time to time and formaldehyde can be used in order to kill the insects oftenly.
Before we operate the laminar flow it should be made on 15 min before we start work.
The temperature of the lab should be maintained.
During the inoculation use the proper gloves, apron and mask.
The inoculation needle should be made clean during inoculation.
The culture should not be very old.
Spawn with the green and brown colour indicates they are damaged.
Prevent it from bacteria.
A well done spawn is tight and is a pure white in colour.
Also visit the following for production of mushrooms
Production of oyster mushroom
Production of button mushroom
Also visit the following for production of mushrooms
Production of oyster mushroom
Production of button mushroom
