Chapter 290 - 151: Root System (Middle)

Chapter 290: Chapter 151: Root System (Middle)

About six months ago, while tending to his experimental fields, Jiang Miao discovered that the three new soybean varieties were exhibiting a kind of atavistic trait.

In many people’s minds, crops like soybeans, rice, corn, wheat, and millet are typically planted once, and after harvesting, they must be replanted the following year.

But in reality, this is a misconception.

The vast majority of herbaceous crops cultivated by humans today, whether they belong to the legume family, the Poaceae family, or the mustard family, exhibit an annual or seasonal life cycle because of human breeding, not because that is their original nature.

Those in the south who have grown rice will likely know that after harvesting, if the root system is left intact and given proper care, it can sprout anew.

In other words, a large portion of the ancestors of the herbaceous crops cultivated by humans today were perennial herbs.

Likewise, soybean ancestors also included perennial varieties.

In fact, some wild soybean varieties in the southern regions still retain their perennial growth characteristics.

The parent stock Jiang Miao used to cultivate the new varieties included several wild soybean types. However, after hybridization and induced genetic mutation, the genes from these wild soybeans accounted for only one-eighth of the new varieties’ total genetic material.

However, all three new varieties developed through induced mutation exhibited a new trait: water-storing root tubers. This, in turn, activated the cluster of perennial genes hidden within the new soybeans’ DNA.

In the experimental field, these soybeans would sprout anew from their roots about half a month after being harvested. With sufficient fertilizer, light, and heat, they would quickly flower and produce pods again.

Furthermore, the existing and relatively mature root system offered a significant advantage. Legumes naturally form nitrogen-fixing nodules, and after one growing season, the vast network of these nodules provided ample organic nitrogen for the next cycle.

At the same time, another characteristic of the new soybean varieties—the water-storing root tubers—provided an abundance of water, vitamins, and small amounts of sugars and amino acids for the soybean’s secondary growth.

In fact, the root tubers of these new soybean varieties are somewhat similar to another branch of the legume family: kudzu.

Although compared to kudzu root, the root tubers of the Immortal Bean series have a low starch content. Their water content is as high as 83%, with starch at around 3%, the remaining 12.8% being cellulose, 0.7% fructose, and 0.5% other components.

Thus, the Immortal Bean’s root tubers are similar to the yacon—the so-called "fruit" of the tuber world.

Of course, Immortal Bean root tubers cannot be eaten as a fruit or a vegetable, because they contain a considerable amount of trypsin inhibitors and soyagglutinin. They will cause poisoning if eaten without being cooked thoroughly.

With these root tubers, the Immortal Bean’s hidden perennial trait was directly activated.

As long as a certain amount of phosphorus and potassium fertilizer and trace elements are supplemented, along with one application of plant growth hormones and one of foliar fertilizer, the growth cycle of the second-crop Immortal Beans will be much shorter than the first.

Sprouting occurs around day 12 to 15, flowering from day 28 to 30, and podding begins between day 33 and 35. The flowering period ends by day 50 to 55, the first pods start maturing between day 65 and 68, and by day 85 to 90, all pods are mature and ready for harvest.

In the experimental fields, the measured yield of the second-crop Immortal Beans showed no significant difference from the first crop.

Although its growth cycle was shorter by over ten days, the second crop had a head start.

Of course, if this were all, it would still be impossible to grow a second crop in the Monan Region.

After all, the annual frost-free period in Zhelimu City is only 140 to 160 days. Once you account for the time needed at the start and end of the season, there isn’t enough time to guarantee two full soybean growth cycles.

What truly surprised Jiang Miao was the cold tolerance exhibited by the Immortal Bean series. He simulated the Monan climate in his lab and discovered that the Immortal Bean’s root system could safely survive a Monan winter. It would then rapidly send up shoots in March of the following year. In their seedling stage, they could withstand temperatures as low as minus 10 degrees Celsius. As long as the daytime temperature rose above zero, they would begin to sprout vigorously.

Starting their growth in mid-March, they are ready for harvest 90 days later, around mid-June.

After the harvest, a second growth cycle begins in early July. All pods are mature by early October. However, to allow for greater nutrient accumulation in the roots, the harvest is delayed until the end of October. Once harvesting is complete, it is early November.

In Monan, early November temperatures are typically below freezing. This inhibits the Immortal Bean’s subterranean root system from sprouting again, forcing it to conserve its ample store of nutrients and water to survive the winter.

This makes it possible to harvest two soybean crops a year. Moreover, this method eliminates the need for annual seeding and irrigation.

The Immortal Bean series only requires supplemental watering during its initial germination period when grown from seed, which boosts its germination rate and growth speed.

In Jiang Miao’s experimental field, the first batch of Immortal Soybeans planted had already completed its third harvest this March. Its yield not only didn’t decrease but actually increased by about 10%.

Especially in the experimental plots simulating a sandy soil environment, the third-crop soybeans saw a yield increase of about 17%.

The reason this occurred was the continuous expansion of the root system into the surrounding sandy soil.

Soil conditions in red clay farmland or clay-heavy paddy fields are unfavorable for the rapid expansion and deep penetration of the soybean root system.

In sandy farmland, however, the Immortal Bean series demonstrated shockingly aggressive growth.