Most plants suffocate when you submerge them for an extended period of time. So, how does rice breathe? It turns out that not all plants need to breathe through the ground. Rice and mangroves are an example:
Generally plants need their roots to have some access to air (soil air) for respiration (breathing). However, some plants are adapted to living in situations where their roots are always wet. The classic example is mangroves, but rice is another. These plants develop alternative ways to get air into the plant. In mangroves they grow special roots that stick up out of the water like a snorkel. For rice, the stem is able to absorb air, so rice can breathe through its stem instead of its roots. The rice roots are also adapted to extract some oxygen from the water.
For reference, this is how you grow rice:
- Collect all of your clean plastic buckets and empty plastic laundry soap buckets to work in. You do not want to use any container that has holes in the bottom that would let the water out.
- Buy some long-grain brown rice from the bulk bins at the grocery store or in a bag. Organically grown rice will reproduce better than some long-grain brown rice, but most kinds seem to have some grains that sprout. Your goal is to find brown long-grain rice that is as close to untouched by machines and chemicals as possible. White rice will not work because it has been processed. Or, you can buy a package of your favorite rice seed from a gardening supply outfit.
- Fill your buckets with about 6″ of dirt or potting soil. Add water until it is about 2″ above the soil level and toss a small handful of your store bought long-grain rice into the bucket; they will sink so that they are lying on top of the dirt under the water.
- Rice likes a warm climate, keep your bucket in a sunny area and move it if necessary to a warm place at night. Keep your water level at about 2 inches above the dirt until the rice is growing strong.
- When your plants are up to about 5-6 inches, increase your water level to about 4 inches deep. After that, let the water level lower in the bucket slowly over a period of time. You will want the plants just about dry of standing water by the time you are ready to harvest.
- Rice is mature somewhere in its fourth month if conditions are right. The stalks will change from green to gold in color when they are ready. To harvest, cut your stalks and let them dry in a warm place, wrapped in a newspaper for 2-3 weeks.
- Roast your rice in a very low heat (under 200) for about an hour, and then remove the hulls by hand. You are now ready to cook with your own long-grain brown rice.
I saw this along the way:
Q: Why do plants with more access to water need more stomata?
A: Plants move water from soils to leaves through a passive evapotranspiration process which provides more hydrogen ions for photosynthesis. Therefore the movement of water does not require energy and is contingent upon the amount of stomata and water available. In the case of some herbaceous plants, this water movement will also provide turgid support for leaves and stems. If water is plentiful (not limiting) then plants may have more stomata, which allows for greater access to water (and the hydrogen ions needed), and increased support for herbaceous tissues.
Another interesting statement regarding the fact that an estimated 45% of the water used for irrigation in the world goes to rice:
World Water Day arrives again on 22 March. For me, it’s time to reflect on the relationship between rice and water—two of the world’s most precious commodities that are so intimately linked. The world produces some 700 million tons of paddy rice each year. This is enough to provide the staple food for more than three billion people, of which some 700 million live in poverty. The majority of rice is grown under irrigated conditions in which the fields are flooded from planting to harvest. Because of this flooding, rice is said to use a lot of water, about two and a half times the amount of water needed to grow a crop of wheat or maize. To ensure good yields, farmers and governments throughout the centuries (even millennia!) have developed irrigation infrastructure. And, since there are some 160 million hectares of planted rice land, rice has become the biggest single user of “developed” fresh water worldwide. Using some simple calculations, I once estimated that all the rice land receives 35–45% of all the world’s irrigation water (which itself uses some 70% of all the world’s developed water resources). Thus, rice is often portrayed as a “profligate” user of water—a crop we should stop growing to preserve our rapidly dwindling freshwater resources! So, should we?