Why are the cut water bamboo stalks covered in black spots? Can I eat it?

Tell me first what ingredient this is, haha

Water bamboo shouldn’t be eaten like this; it’s recommended not to consume it!

If we were to rank plants based on their seniority, arrowhead would definitely be considered the number one. This grass species of the genus Zizania was, in its time, a food crop that could be considered on par with the \"five grains\". During the gathering era and in the early stages of agricultural development, the seeds of the arrowhead plant – arrowhead rice – were once used as an important food source. In ancient texts such as The Rites of Zhou, the ancients even classified glutinous rice as the sixth grain, on par with the five major grains of rice, millet, foxtail millet, wheat, and soybeans. In fact, all grasses have seeds rich in starch; it’s just that some seeds are too difficult to collect (such as the African wild rice that grows in water), some are too small (such as reeds), and some cannot be harvested at regular intervals (such as bamboo). Relatively speaking, arrowhead rice is a grain that is relatively easy to harvest and utilize. Moreover, kudzu is a perennial plant; once planted, it can provide us with food for a long time, just like fruit trees. However, the yield of arrowhead rice is far inferior to that of rice. Coupled with the long flowering period of the arrowhead, the uneven maturity of its seeds, and the fact that the seeds fall off the spikes as soon as they mature, it is a rather difficult-to-cultivate grain crop; as a result, it was gradually abandoned by people over time. After being abandoned by the main group of food crops, cultivated arrowhead found a new home in vegetable stalls, and those infected with rye rust reappeared.

The rhizomes of cultivated water caltrop become deformed due to fungal infestation, producing vegetables that resemble bamboo shoots – these are water bamboo shoots. Not all cultivated water caltrops can produce water bamboo; the stems of those that are not infected remain in their original state, and thus are referred to as \"male water bamboo\". The stem of the infected plant is abnormally swollen. Image: jichitube.com Generally, we think that the relationship between plants and microorganisms is one of conflict – such as Penicillium, which causes citrus to rot, Aspergillus flavus, which makes peanuts toxic, and yeast, which leads to rotten apples. But some microorganisms and plants can coexist peacefully, each getting what it needs. The most typical examples of symbiosis in nature are the rhizobia in leguminous plants and the symbiotic fungi in orchid plants. In these two typical parasitic events, the plant hosts play a dominant role; they create spaces specifically for these microscopic organisms to live in. Of course, the microbial tenants don’t live there for free; they serve the host. The rhizobia of leguminous plants convert nitrogen from the air into fertilizer that plants need, while the symbiotic fungi of orchid plants help them absorb water and mineral nutrients. If we have observed the roots of orchids, we can understand the mystery of the symbiotic fungi—orchid roots are bare, without any root hairs, because the fungi have completely taken over the function of those root hairs. This is a typical symbiotic relationship in nature.

Of course, the smut fungus and the arrowhead do not have such a peaceful relationship. As we mentioned earlier, sweet flag plants infected by the black mold can no longer produce seeds. Furthermore, the Ustilago fungus secretes certain chemicals to stimulate the swelling of the arrowhead’s stems. You should know that the stems of normal arrowhead plants are about as thick as those of rice plants; at most, they are as thick as ordinary chopsticks. However, the swollen stems can reach the thickness of rolling pins. This has allowed the Ustilago fungus to greatly expand its habitat. Once the growth period of the arrowhead plants is over, many spores of smut fungi are released to infect new plants.