Legislator finds new solutions to save crops from pests

Zhang Keqin, a national legislator and an agrarian from the biodiverse Yunnan province, is well aware of the central part that science and technology plays in consolidating safe and secure food supply.

Zhang, an academician at the Chinese Academy of Sciences, was elected a deputy to the 14th National People's Congress, the top legislative body, last month. He has devoted his life to finding bio-solutions to control pests.

"Over the past three decades, my colleagues and I have helped created a microorganism bank that can help check the spread of nematodes," the 65-year-old said on Sunday at a delegates' passage interview on the sidelines of this year's two sessions, the annual meetings of NPC and the Chinese People's Political Consultative Conference National Committee, the top political advisory body.

Nematode are unsegmented worms with elongated rounded body, the former vice president of Yunnan University explained to a pool of reporters at the Great Hall of the People in Beijing. The worms can cause tumor-like lumps at crop's roots, and have been nicknamed cancer of plants. Because of them, plants wither and become infertile and yield-less, he said.

There are various types of the worms, and more than 5,000 are deemed destructive to plants. The annual crop loss due to the pest is estimated at $157 billion globally, he said.

"Don't ignore it as too tiny, it has close connections with all of us," he said.

That is because much of the world is still heavily reliant on pesticides to tackle the worms. Since soil is itself corrosive to chemicals, pesticides are usually applied in large amounts. The practice can lead to contamination of soil and underground water. The chemical residues in crops also have an immense impact on human's health, he said.

Yunnan province, though accounting for only 4 percent of China's land areas, is home to more than half of the country's plant and animal species, and proves to be an ideal place to carry out experiments over bio-control methods for pests such as nematodes.

"More effective control of the worms needs us scientists to better understand the interrelations among micro-organisms, crops and nematodes," he said.

Zhang said that nematodes are rather clever living things. They can detect the chemicals released by the growing plants' root system, and pinpoint the location of their preys.

In light of that, "We selected a number of chemicals that appeals to the worms and lure them to a microorganism trap," he said.

"After the theoretic breakthroughs over such complicated biomolecule mechanism was made, our team developed three bio-solution products, which had been promoted for widespread use," he said.

The application of such products in a sweet potato- and tomato-growing village in Yunnan has led to decline of infection rate of nematodes from over 90 percent to just 2 percent over the course of four years.

"The quality and yield of tomatoes have improved notably, and what's more important is that such tomatoes are free of chemicals," he said.

Science and technology are the central plank to ensuring safe and secure farm produce supply, he noted. "As a legislator in the agricultural sector and an agricultural scientist, I am obliged to make my due contribution to the national strategy of invigorating farming sector."