How can seeds be made to use less fertilizer and produce more grain?

Want to make farmers use less chemical fertilizer? Perhaps seeds can be made to absorb fertilizer better. Huang Jianhua, director of the Biotechnology Research Institute of the Shanghai Academy of Agricultural Sciences, is using barley seeds as a breakthrough point to study the efficient utilization of nitrogen fertilizer. If this research succeeds, it can raise the nitrogen fertilizer utilization rate of crops from the current about 35% to about 60%. This will also benefit rice and wheat, which are closely related to barley, and provide support for shared breeding technologies as Shanghai builds a basic innovation platform for seed-source agriculture.

China's agriculture has long been criticized for its high fertilizer consumption. Rice yields per unit area are similar to Japan's, but nitrogen fertilizer use is 3 times that of Japan. "Just as everyone's appetite differs, crops also differ in their fertilizer absorption rates," Huang Jianhua said. "At present, the average nitrogen fertilizer utilization rate of crops is only about 35%, which also means that most fertilizer, because it cannot be absorbed by crops, flows with farmland drainage into rivers, lakes, and seas or seeps into the soil." According to statistics, this kind of pollution has already become one of the main sources of agricultural non-point source pollution in China.

China is building an environmentally friendly and resource-conserving agricultural development strategy, and reducing the use of pesticides and chemical fertilizers is one of its major priorities. Huang Jianhua said that to reduce pollution, one "fundamental" approach is to start by improving crops' ability to absorb nitrogen fertilizer and reduce the loss of chemical fertilizer. At present, he is leading a project called "New Methods for Fertilizer-Saving, Disease-Resistant, and Drought-Resistant Germplasm Innovation Based on Cellular and Gene Levels," which plans to use 3 to 5 years to breed a new barley variety that can efficiently absorb nitrogen fertilizer, ensuring that yield, quality, and other factors remain on par while using 20% to 30% less fertilizer than conventional application.

Anyone even slightly familiar with agriculture knows how difficult it is to develop a new variety in 3 to 5 years. From selecting the desired traits to hybridization and homozygosis, and then to breeding a stable variety, it is not unusual to spend 10 years. Huang Jianhua said, "In recent years, foreign breeding technology has advanced by leaps and bounds." Huang Jianhua is referring to the internationally popular molecular marker technology and doubled haploid technology. The former can quickly screen crops for desired traits at the molecular level, while the latter can quickly stabilize traits to form new varieties. With this composite breeding technology, a new variety can be released in just 3 to 5 years.

Huang Jianhua has deep research experience in doubled haploid technology, but in trying to release "nitrogen-efficient seeds," he is troubled by the lack of a good molecular marker. "In fact, in breeding technology, which has the highest technological content in agricultural science, China still has a considerable gap with foreign countries."

Huang Jianhua said that in the past, China's main goal in crop breeding was high yield, but today factors such as nutrition, nitrogen efficiency, and resistance to pests and diseases have also become increasingly important. Developing China's own molecular breeding technology is another goal he has in mind.

Not long ago, Dutch Bulita eggplant seeds priced at 100,000 yuan per jin made people realize that agricultural products can also sell for the price of an Apple phone. However, becoming seeds that can fetch a high price requires a great deal of scientific research. Huang Jianhua said that world seed industry research has moved from the traditional conventional technology breeding stage to the stage of relying on biotechnology breeding. Global seed industry giants have invested huge sums in biotechnology and new variety research and development, developing a large number of new corn, cotton, and soybean varieties carrying target genes such as disease resistance, insect resistance, and herbicide tolerance, and they attach great importance to the collection of germplasm resources. Through mergers and acquisitions, multinational companies have not only acquired technology and markets, but also controlled a large amount of germplasm resources.

Several years from now, Huang Jianhua hopes to integrate nearly 30 years of breeding experience into shared technologies and build a basic innovation platform for seed-source agriculture for Shanghai. "The construction of an agricultural science and technology system is an important part of building a science and technology innovation center. To accelerate the development of modern agriculture, Shanghai must seize the seed-source link with the highest added value," Huang Jianhua said.