The level of agricultural science and technology in Datang is very low, and the grain output is also very low. The main base of the pen ~ fun ~ pavilion www.biquge.info Datang is the Shaanxi area. The main food crops are wheat and millet (millet). The yield of wheat is about 250 catties per mu in watered fields and about 120 catties in dry fields. Millet is completely dependent on the sky for food, and the yield per mu does not exceed 100 catties.

The situation is similar in other provinces. Jiangnan is a little better, but there are not many places to develop, and the main grain producing area is only Yangzhou.

At this time, the population of the Tang Dynasty was only about 14 million people, and the land area was vast, so such a low grain production could maintain normal consumption in the absence of natural disasters.

"Mixing and waiting for death" is Li Su's great ideal, but in front of the word "eat", there is also the word "mixed". You have to do something to live, right? "Mixing" also has to be mixed.

Li Su himself has a fief, and the actual fief is 300 households, and the grain handed over every year is very pitiful. After he crossed over, he started to think about increasing food production.

He said to Tang Taizong: "Father, the son has a way to increase grain production. ”

When he was young, he studied history intensively and once thought that if he had the opportunity to govern the country, he would definitely create an unprecedented prosperous era.

After becoming emperor, he became more ambitious, exhausted, and worked hard. Under his leadership, Datang has made great progress.

However, the Tang Dynasty was built on the foundation of the former Sui Dynasty, which was riddled with wars. At the moment when everything was in ruins, there was internal rebellion in Datang, constant border troubles, and various natural disasters. Li Shimin felt that it was difficult to walk.

Among all the problems of Datang, the most urgent and difficult problem to solve is the food problem. The people take food as the sky, and they can't solve the problem of eating, so everything is not to be discussed.

At this time, Datang had already implemented the equalization system, and the cultivated land area was guaranteed, but the grain output was really low, and coupled with the drought last year, grain was very scarce.

At this moment, Tang Taizong couldn't help but be overjoyed when he heard Li Su's words. He said, "What's the solution? ”

Li Su said: "Erchen thinks that the low grain yield is mainly due to the problem of farming methods, the depth of cultivated land, the suitable varieties, the time of sowing, and the number and timing of irrigation, etc., which will affect the grain yield. It is necessary to pay attention to the scientific nature of grain planting. ”

At this time, Li Shimin interrupted him and asked, "What is scientificity?" ”

"Let's put it this way, growing grain is also a craft, and we must pay attention to skills, and skills are scientific." Li Su said.

Li Shimin said: "Oh, I see. You go on to say. ”

Li Su read a large number of materials on grain production in Shaanxi, and he wanted to give a science popularization lesson to the top sages of the Tang Dynasty in front of him.

First of all, he told them about the impact of Shaanxi's geographical location on grain production, and talked for a long time in the north and south of the Qinling Mountains, in Guanzhong and Hanzhong, and in the clouds and mountains, to prove that he had worked hard and was not untargeted.

As a result, Li Shimin became impatient when he heard this, and he asked directly: "Tell me, how much can the grain output be increased?" ”

Li Su said: "The yield of grain per mu is more than 300 catties. ”

There is a basis for this production of his. The yield of general varieties of millet is 600~800 catties, and the rice yield is 70~75%. However, with the development of science and technology, all kinds of hybrid millet have come out one after another, and the yield per mu is also growing rapidly, such as: on a test field in the lower garden of Zhangjiakou City, the highest yield per mu of "Zhangzagu No. 5" has reached 1720 catties, creating a world record.

When calculating the yield of millet, Li Yu fully considered the irrigation conditions, chemical fertilizers, pesticides and other factors, and gave a very low value when he could search for scientific planting methods and Taobao to obtain high-quality seeds.

"What?" Li Shimin sat up straight in surprise, and he said, "How many catties?" You repeat. ”

Li Su said affirmatively: "The yield of grain per mu is more than 300 catties. ”

"Great, if the millet can reach such a yield, it will almost double the increase, Your Majesty." Eldest Sun Wuji said excitedly.

"yes, that's unbelievable." Fang Xuanling was also a little excited.

"That's where it goes." Li said in his heart. He continued: "The yield of wheat per mu can reach 400 catties. ”

In 2014, Xianyang 10,000 mu of high-yield demonstration plots averaged 596.67 kg per mu, including a high-yield party, with an average yield of 724.16 kg per mu. Eight districts and counties in Xi'an have implemented high-yield wheat production, with the highest yield per mu exceeding 600 kg.

Li Su also gave a third of the yield per mu.

Li Shimin stood up excitedly, and he asked, "Are you sure?" ”

Li Su said affirmatively: "Erchen is sure. ”

Li Shimin slapped his hands hard and said, "Okay, if that's the case, the Datang grain problem can be fully solved." ”

Speaking of this, he said to Li Su: "Su'er, if you can really do this, what you want, your father will give you something." ”

Then, he said to the eldest grandson Wuji: "Auxiliary machine (the character of the eldest grandson Wuji), you will take the lead in this matter, and let Li Su be specifically responsible." First conduct a test near Chang'an, it was successful, and it will be widely promoted next year. ”

"Obey." The eldest grandson Wuji replied.

Li Shimin walked around the ground excitedly.

"Father, my sons still have something to say." Li Su said.

"Oh, you name it." Li Shimin sat back on the couch and said.

Li Su said: "Erchen can grow rice in the south in Guanzhong and the Hanjiang River basin, with a yield of 800 catties per mu. ”

Xi'an, September 12, 2016 (Xinhuanet) -- Recently, after the acceptance of rice yield experts, 55 households including Cheng Yuping and Zou Gen in Xinhua Village, Longtou Town, Chenggu County, a high-quality rice producing area in southern Shaanxi, had a yield of 767.1 kg per mu, more than 260 kg higher than that of ordinary fields, creating a new record of high rice yield in Shaanxi.

Li Shimin was a little dizzy: planting rice in the north yields 800 catties per mu!

Next, Li Su said: "There is one season every year in the north of the Qinling Mountains, and two seasons in the south every year. ”

"What?" Li Shimin was so excited that he stood up again.

Seeing Li Shimin's appearance, Li Su was a little scared, he took a step back and said: "Father, there is still a kind of grain that can be planted, this kind of grain is called potato, also called potato, with a yield of 4,000 catties per mu!" ”

On the morning of June 16, 2015, in Lion Village, Pu Town, Hantai District, Hanzhong City, the innovative use of spring sowing "double coverage" technology planted potatoes yielded 9,600 catties per mu, which was 1-2 times higher than the yield of traditional potatoes.

Potatoes are native to Peru and Chile in the Andes Mountains of South America. It was introduced to China during the Ming Dynasty. Li Su has a Taobao system, so it is not a problem to get seeds.

"Bang", Li Shimin took a step forward and slapped his palm on Li Su's head.

"Oh, father, why are you beating your sons." Li Su said aggrievedly.

"There's such a good thing, why didn't you say it earlier?" Li Shimin said happily. After speaking, he stepped forward and hugged Li Su, and said with a slight choked voice: "My good son." ”