Plant tissue culture couldn’t be practiced without sterile vessels to hold your media and plant material. Luckily there are many types of containers that can be used which are easily sterilized and used. Most of them are also reusable and can be found easily to repurpose.
Being creative when looking for potential vessels can save a lot of money. Friends and coworkers often will save their glass containers for you if you notice they have a habit of drinking or consuming from suitable containers. Certain sizes have benefits in certain stages and paying attention to the best use of materials and space will provide the most return.
Thin test tube vessels make great initiation phase vessels while wide-mouth canning jars make exceptional vessels for multiplying fast growing bushy plants. Baby food jars are in the middle of the aisle as they offer good space saving potential while keeping plenty of plantlets safe and happy. Both are easily found and autoclavable heatproof lids are available from tissue culture supply houses.
Larger vessels offer the option of allowing plantlets to grow and use up hormone to begin rooting, saving steps. Bigger jars can be used for fast-growing multiplication stages to be split and replated quickly in order to multiply efficiently. Smaller jars allow for a higher number of explants to be initiated as they use less media, this is handy for hard to clean or fragile explant material so that they can be attempted in larger numbers resulting in higher odds of clean initiation. Each size has its own benefit and setbacks. Using these benefits will create advantages and increase productivity.
Vessels must be made of materials that can withstand the high heat in the autoclave or pressure cooker. Glass can most easily withstand these temperatures but not all plastics can. For this reason, PP, or polypropylene, plastics are used in the autoclave. Most plastics marked with PP can be autoclaved, with some limits. Thin deli tubs marked PP can be used with enough venting provided to allow them not to crush when cooling down from the force of cooling vacuum.
The most trusted and widely used vessels throughout the industry are specially made for plant tissue culture. While they are the most durable and reliable they are also the most costly option. There are many great commercially available vessels in many configurations. They are largely very durable and will last for an extended time. Some options include square containers for saving space, round ones with screw on lids, and easy to use slip on lids for glass containers.
Some of these commercial vessels easily cost 10 US dollars each or more. In the long term it will amortize and pay itself off but those wanting or needing to start on a tight budget might opt for a more cost friendly option.
Baby food jars are an excellent vessel to use when trying to save money. The metal lids that come on the jars can be reused by poking a hole in the lid. Small round bandages used for shaving nicks can be placed over the hole to keep it sterile after autoclaving.
Another option is to use a larger hole and use a rectangular piece of sponge shoved into the hole. The sponge method allows the lids to be reused several times where the bandage method needs the bandage replaced each time. The benefit of the bandage method is that they are easier to stack.
The supply company Magenta makes a lid for use with baby food jars. They offer vented and non-vented plastic caps that slip on over the glass baby food jars. Magenta B Cap lids help make the job easier by allowing the cap to be easily put on after plating. Even some smaller commercial labs use baby food jars with Magenta B Cap lids. The vented lids are my favorite.
Ads placed in local newspapers or online For Sale/Wanted sites are good resources for baby food jars. Thrifty and eco-friendly parents will save baby food jars for reuse and offer them occasionally but the best results come from offering a small amount per useable baby food jar in the local wanted/for sale ads.
Canning jars make also very useful and versatile vessels for plant tissue culture. Canning jar sized lids are available from Magenta that fit the threads of half-pint, pint, and quart jars in both regular and wide-mouth sizes. These jars are easy to gather and the lids can be purchased in lots of 100 for convenience if you need that many at a time. Canning jars can often be found on For Sale and Wanted sections in local papers and online sites also.
Almost any glass canning jar can be used as vessels in plant tissue culture. Single serving cold coffee drink jars with a wide mouth work very well for most plants and are easy to find. Most glass jars like this will need to have the lid reused for several times using the vent methods but will rust eventually. Light rust doesn’t seem to have an effect on the sterility of vessels but when it scales it should be replaced. Replacing missing or damaged metal lids with tin foil is an appropriate method but will allow for slightly higher numbers of contaminated vessels as they do not seal as tightly and securely.
Polypropylene plastic deli tubs can be used and are cheap to use. 16 ounce to 32-ounce bins are easy to find. The problem with them is that they are thin and will collapse under the weight of each other when autoclaved if not stacked carefully. They must be evenly placed to disperse the weight of the ones above them by alternating them at a 45-degree angle so that two are below the one on top.
Deli tub lids must be well vented using the sponge or bandage method. If they are not highly vented either the expansion from heating will push the lids off or the contraction from cooling will suck them flat and make them unusable. 2 or 3 spot bandages with a 1/4 inch hole is usually enough ventilation. Test your deli tubs with your method of autoclaving to make sure before processing an entire batch to make sure you have the method working.
32-ounce deli tubs also make an excellent container for taller plants, like bamboo, or fast growers. Extra height allows for longer growing times in vessels so that plantlets can start rooting on their own after they use up the plant hormones in the media. Plantlets can sometimes go straight from multiplication to hardening off, or even moved to the greenhouse while still in-vitro to acclimate while saving steps and ultimately time.
Test tubes made of glass are useful for initiation and small plantlets. Glass test tubes can use a sponge cube shoved in the top to protect the opening from contamination. Polypropylene test tubes made for plant tissue culture are especially handy and are available from most online plant tissue culture suppliers. Look for flat bottomed test tubes as they are much easier to work with as they stand on their own.
Test tubes with screw on lids make it very easy to use, especially when plating explants. Initiation phases often use only one or two explants per vessel to lower chances of contamination and the small size of test tubes is perfect for making the most out of resources. Media goes a lot further in smaller vessels which means more explants can be initiated with the same amount of media. You will lose explant initiations to contamination or other reasons, and the more you start the higher your chances of success.
Another alternative are polypropylene plastic bags. They are cheap and fairly easy to work with in the multiplication stage. They are better suited only for the multiplication stage to growout. The top is rolled and secured with a paperclip. Venting with spot bandages worked well enough for me. Coarse sand as a media gelling agent works well enough as it helps support the bags better but agar will work. Overall they are cumbersome and finding quality bags that wont melt is harder. They are difficult to replate as the bags are hard to get material in and out to divide cultures.
Whatever vessels used must be able to withstand the high heat of an autoclave or pressure cooker. Never put a jar and lid in the autoclave or pressure cooker that is completely sealed. It must be vented with a slightly loose cap to avoid accidents. Glass jars should be free of nicks and chips as heating and cooling can easily break a damaged glass jar.
When screwing on jars screw the lid snug then back off one-quarter of a turn. If the jars cannot vent they may very well explode inside the pressure cooker or autoclave.