Chen Chengxian and soybean researchers went to check the growth of soybeans.

After getting all the details of the soybeans, Chen Cheng returned to an office that Mr. Zheng had arranged for him.

He had a laptop with him, and of course he had to open it for a show.

The "secret weapon" is still the super agricultural technology system in his head.

Calling up the system, Chen Cheng entered the soybean raw information.

His main purpose this time was to explore and breed soybean varieties with well-developed root systems, so he first paid attention to the 3D virtual soybean plant root system.

The root system of this soybean variety is slightly more developed than that of autumn soybean in Hanxi Province, and the main root is thicker.

A strong taproot means that it is more resistant to lodging, and the deeper the root, the stronger the drought resistance.

The roots of soybeans are divided into main and lateral roots, which can penetrate into the soil at a depth of 1.5 meters and have a bell-shaped root system. Soybeans have a straight root system and are divided into taproot and lateral roots. The root system of soybean is composed of taproot, lateral root and root hair, which supports and fixes the plant and absorbs nutrients and water. The taproot is formed by the elongation and development of the seed radicle.

The taproot depth of soybean can reach 180cm and expand horizontally by 35~45cm, but the main root system is distributed in the tillage layer about 0~20cm deep.

Chen Cheng clicked on the 3D virtual image of the soybean plant, then zoomed in to observe it.

He found that the soybean plants grown in the laboratory had more rhizobia in their roots than the autumn soybeans in Hanxi Province.

"It's probably the result of their selection and cultivation."

Chen Cheng thought about it, and his eyes fell on the distribution of rhizobia.

He found that although the soybean of this variety has a well-developed root system and a long taproot, the rhizobia are concentrated in the upper part of the taproot and do not grow to the lower part of the taproot and lateral roots.

Chen Cheng hurriedly looked through the literature in the supercomputer and quickly figured out this problem.

Soybeans are deep-rooted crops with a wide and deep root distribution, which puts high demands on the soil in which soybeans are grown. In cultivation and planting, it is necessary to carry out proper deep ploughing and fine land preparation, and the depth of ploughing should be about 20 cm.

At the same time, the combination of deep fertilization and layered fertilization creates a good soil structure, increases porosity, air circulation, and enhances the ability of water storage and drought prevention, which is conducive to the growth of soybean roots and the reproduction and growth of rhizobia, and is conducive to improving soybean yield.

But this brings up another problem.

That is, rhizobia are not adapted to live in deep soils.

The source of nitrogen for nitrogen fixation in rhizobia is air, which is ineffective if it is deep in the soil, and the rhizobia do not develop better.

"Devouring the Starry Sky: Signing in to Become a God"

The nodules are produced by the action of rod-shaped rhizobia with 1 ~ 2 flagella at one end, it is an aerobic bacterium, which mainly grows on the root system 20 cm near the ground.

The diameter of the nodule is generally 4 ~ 5 mm, which is green at the beginning, gradually turns light red, and finally turns dark brown.

Carbohydrates and other nutrients are delivered into the human nodules by the vascular bundles in the soybean roots to maintain the growth and reproduction of the root nodules.

In turn, rhizobia fixes the free nitrogen in the air, and in addition to self-sufficient nitrogen nutrition, the excess part is supplied to the growth and development of soybeans, which is the symbiotic relationship between soybean and rhizobia.

Therefore, in the process of soybean planting, farmers need to carry out fine planting, especially the soil treatment requirements are higher.

Other crops generally need to plough the land before sowing, but soybeans need to be ploughed, ridge cropping, raking, subsoiling and other land preparation techniques in addition to ploughing.

Because soil moisture status, nutrient status and some physical properties of the soil are important factors affecting soybean yield.

Soybean seeds require more water to germinate than cereal crops. The young roots of soybean are tender and have a large water content, and suitable soil moisture conditions can promote the elongation of young roots to depth. When the soil is suitable, the taproot of the plant can reach about 1 meter, and the lateral roots can expand in parallel to about 0.5 meters.

However, when the soil moisture is insufficient, it will affect its longitudinal and horizontal expansion. At the same time, soybean roots are sensitive to changes in oxygen in the soil. Under hypoxic conditions, root growth is significantly reduced.

Therefore, moderate soil moisture content, deep tillage layer, and moderate tightness can provide good water content and aeration conditions, which will promote the growth and development of root system.

So, under these constraints, farmers will have to spend more manpower if they want to increase soybean yields.

This is where Chen Cheng wants to change.

"Started iterative simulation experiments to breed the offspring of soybean varieties with well-developed root systems."

Chen Cheng directly started the simulation, preparing to use the supercomputer to simulate the iteratively cultivated soybean varieties just like last time.

Soon, the supercomputer was able to simulate soybean varieties with well-developed root systems based on the conditions he set.

"Well, the root area has increased by 64%." Chen Cheng thinks this data is okay.

But when he implanted rhizobia into it and started a symbiotic simulation, the problem arose.

The implanted rhizobia still clustered near the upper part of the taproot and did not spread to the periphery of the larger lateral roots.

That is, the effect of rhizobia is not exerted.

It should be known that under normal cultivation conditions, rhizobia can fix about 3~3 nitrogen per mu. 5 kg, equivalent to 17.5 kg of ammonium sulfate. The rhizobia provides one-half to two-thirds of the nitrogen it fixes for soybean uptake.

Therefore, the quality of nodule development and the activity ability of rhizobia directly affect the growth and yield of soybean.

Chen Cheng selects and breeds soybean varieties with well-developed root systems so that they can carry more rhizobia.

But the problem now is that rhizobia don't grow on them.

It hurts.

After repeatedly checking the simulation process, Chen Cheng found that this is related to the habits of rhizobia.

First, rhizobia need to survive in shallow soils, where they are more likely to be exposed to nitrogen in the air.

Secondly, the reason why rhizobia are mainly concentrated on the taproot is because the structure of the taproot and the lateral root is different.

The cortex of the taproot is thicker and has a larger cross-section. After symbiosis with rhizobia, they are able to multiply and develop very quickly and clump together to form rhizobia clusters.

On the lateral roots, rhizobia can only 'fight alone' and cannot form rhizobia clusters, so they have to gather at the taproot.

"How can you let them gather on the lateral roots and form nodules?"

Chen Cheng thought of a way to continue to increase the lateral root capacity.

That is, to make the lateral roots of the soybeans grow thicker and closer to the taproot.

Of course, there must be a loss of some nutrients, but Chen Cheng feels that it is insignificant compared to the benefits obtained after the symbiosis of a large number of rhizobia.

Chen Cheng no longer reasoned, but spoke directly with the results of the simulation.

He continued to iterate on the simulation.

After more than three minutes, the system gave the rhizome-improved soybean after 14 generations.

"87% increase in rhizome area?!"

Chen Cheng himself was frightened by this result.