A team of scientists has genetically engineered new breeds of high-yield varieties of rice, wheat, and other grains that require less fertilizer.
The New Green Revolution
Back in the 50s and 60s, the green revolution, a period when scientists found a way to supercharge agricultural production by adding fertilization, using pesticides, and other management technologies. While the process yielded larger harvests, it came with a cost: the nitrogen fertilizer that supplied the nutrients needed to produce more crops became a threat to the environment and the ecosystem.
A new study led by Xiangdong Fu, a plant geneticist from the Chinese Academy of Science, found a way to reduce the necessity for fertilizer and, therefore, make production more environmentally friendly.
His team surveyed the DNA of 36 rice variety and examined the role of molecules called DELLA, proteins that suppress the absorption of nitrogen in green-revolution crops and make them hungry for more fertilizer. The scientists involved in the study were able to identify two genes that control the nitrogen consumption: one codes the DELLA protein while the other codes for a growth-regulating factor 4 or GRF4 protein.
Fu believes that the GR4, initially thought to increase only grain size and yield, can also counteract the effects of DELLA protein on a plant's ability to absorb and metabolize nitrogen. When they bred the rice to produce more GR4, they came up with short plants with high yields that require significantly less nitrogen.
The findings were published in Nature on Aug. 15.
Toward A More Environmentally-Friendly Future
Xin Zhang, an environmental scientist who is not involved in the study, is excited about the promise of grains requiring less fertilizer and decrease excess nitrogen from wreaking havoc on the environment.
"Human activity is adding too much nitrogen to the planet," Zhang stated. "It's critical to improve the efficiency of the system."
She explained that due to the use of large amounts of fertilizer in farms all over the world, the human race has doubled the amount of excess nitrogen around the world. Zhang also added that saving the world from nitrogen pollution should not end on producing more nitrogen-efficient crops.
Nathan Mueller, an agricultural system expert from the University of California Irving, agreed that farmers should use more precise methods to identify the right amount of nitrogen needed by the crops to avoid excesses.
Jennifer Volk, an environmental-quality specialist from the University of Delaware, shared that the next step should be to introduce methods that lessen the potential environmental damage from agriculture. This includes construction of wetlands with plants that filter excess nitrogen and other nutrients before they end up in streams and rivers.