Image of a series of steps in a hillside, each covered in green vegetation.
Enlarge / A terraced rice field in Vietnam.

Natural gas is used to make NitrogenFertilizer Natural gas is harmful to life on our planet so we should probably stop using it. Nitrogen is needed by food crops. Since the human population is going to grow over the next few decades, and the arable land is going to decline, it is quite the dilemma.

In response, genetic engineers in China have been developing crops that can thrive with less nitrogen, and they made a strain of rice with a higher yield than regular rice. Each grain particle is bigger and the plants flowered earlier. A yield increase of less than 1 percent is what most breeding methods can only achieve in cereals.

One gene alters many

The scientists looked at the expression of a set of genes that are often involved in different aspects of a single function. The focus was on factors that regulate photosynthesis.

In order to find the perfect target, the researchers screened a set of 118 transcription factors previously identified to regulate photosynthesis in rice and maize to find any that were also upregulated in response to light and low levels of nitrogen. They created a lot of rice lines after finding one. It's like demanding to speak to the manager if you want to express a transcription factor like this instead of the individual genes that control it.

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Rice plants were put in fields with different environmental conditions.

All of the rice plants improved their nitrogen use efficiency over a three year period. They had more of the plant than the wild type. They had more efficient transport of nitrogen from their roots to their shoots than wild rice. Even though the plants were grown with less nitrogen, this increased their yield.

The plants were grown in rice paddies and did well in other experiments. Overexpressing the same transcription factor in a strain of rice that was different from the one used in the bulk of the other experiments had the same effect.

Downstream effects

Most of the genes that are affected by this transcription factor respond to salt. The plants did flower earlier when the scientists overexpressed one of the genes, but they were dwarfed and had less yield. The early flowering trait in isolation from the increased carbon and nitrogen use did not allow the plants to build up enough resources in their shortened growing time.

The authors suggest that genome editing could be used instead of the techniques they used to over express this transcription factor in other crops so they can achieve a higher yield. In cases where growing seasons may become constrained and field space may become scarce, such cultivars can be useful. Also war.

The journal science was published in the year 2022.