Background: plant science

I do not need to convince anyone of the importance of studying cancer treatment, heart disease prevention or the mechanisms of HIV/AIDS. The importance of plant science, on the other hand, is not that clear to everyone. This is a shame, because plant science has the potential to save many lives ánd to decrease the negative impact of humans on our planet.

Food shortage and hunger
In 2015 about 795 million people in the world did not have access to enough food to meet the minimum daily dietary energy requirements [1]. This is a huge number compared to the amount of people being diagnosed with cancer, 14 million in 2012 [2], or living with HIV / AIDS, 36.7 million in 2015 [3]. Hunger is caused by many factors, among them economic and political ones.  Environmental factors also explain a large part of food shortage in certain areas. Plant diseases cause 10 to 40% crop loss – depending on who you ask – each year [4,5], drought and extreme temperatures result in additional losses. Increasing temperatures due to climate change and stricter rules for the application of pesticides and fertilizers will increase the severity of these problems in the years to come. And remember, without food, there will be no people to get diseases for which we need to find a cure…

healthcare_sickcare

Increasing food availability through plant science
Plant science encompasses many subfields that together cover a wide variety of topics, including but not limited to: plant disease, plant response to abiotic factors such as light, temperature or nutrient concentrations, plant development, plant interactions with microbes in the surroundings and plant ecology. All of these subfields look at plants from different angles and not all of them have clear follow-ups that will increase food production. However, any extra knowledge that we gather on plants will help us understand them better. Ultimately, this will increase our ability to grow them optimally in the field and thus to increase food production.

A science success story
The discovery of the so-called submergence-tolerant (Sub1) rice varieties is a clear success story showing how data gathered in a laboratory can lead to increased food production. Rice is an important food source for many people, especially in Asia and Africa. While rice is a relatively flood tolerant crop, modern rice varieties do not do well when they are completely under water (submerged) or in low floods over long periods. While several local rice land races are tolerant to flooding, they have other traits that prevent farmers from using them, such as low yields or poor grain quality.

Discovery of a gene that makes rice plants flood tolerant
Researchers were interested in those local varieties, though: they wanted to discover which genes lead to the increased tolerance. They studied this by crossing food tolerant and flood intolerant rice varieties, like in the paper I described earlier on the discovery of another gene, HCR1, that was found to possibly have changed in plants in response to different aboveground water environments to increase plant fitness. Like in the previously described paper, a part in the genome was found to correlate with the phenotype of interest, in this case the increased tolerance to flooding. This part of the genome was named submergence-tolerant (SUB) 1.

Making varieties used in the field flood resistant
After the discovery of the part of the genome that makes local land races flood resistant, people wanted to use this knowledge to increase flood tolerance of varieties used by farmers in the field. In 2003, the International Rice Research Institute (IRRI) started a breeding program in which they crossed land races with SUB1 in their genome on the one hand with varieties used in the field on the other hand. Offspring with the full genome of the agriculture variety with only the addition of the SUB1 part from the land races were selected and distributed among farmers in, among other countries, Bangladesh and India. Large field trials were conducted and showed no difference between Sub1 rice and the original varieties apart from increased tolerance to submergence. This makes sense, considering that SUB1 is only expressed in submergence conditions. As visible in the photo below, Sub1 rice has a much greater crop yield then the commonly used varieties in flooded fields.

The original modern variety on the left, the variety with the SUB1 part of the genome from a local land race on the right
The original modern variety on the left, the variety with the SUB1 part of the genome from a local land race on the right. Photo source

Future
Sub1 rice is a great success. Many parties, such as the Bill & Melinda Gates Foundation, are contributing financially to further distribution and research. For more information, visit the research organization’s  website.

Changing my blog’s focus
I am a plant scientist and very enthusiastic and optimistic about the ways that plant science can contribute to our society. With sufficient funds and talented people I think it is possible to create more success stories like the Sub1 rice variety. In the past months I have realized that only few people are aware of this important possible contribution of plant science to society. Therefore, I have decided to shift the focus of my ‘journal club’ and ‘background’ stories to be mostly plant related. In this way, I hope to open more people’s eyes to the possibilities of plant science. Who knows, maybe one day this increased awareness will result in something like a ‘plant research to feed the world fund’ in addition to the ‘world cancer research fund’ and the many other disease-related funds out there.

Sources
1: The State of Food Insecurity in the World 2015, by the Food and Agricultural Associations of the United Nations. http://www.fao.org/hunger/en/
2:Cancer, by the World Health Organisation. http://www.who.int/mediacentre/factsheets/fs297/en/
3: Global health observatory data: HIV / AIDS, by the World Health Organisation. http://www.who.int/gho/hiv/en/
4: Combating plant diseases is key for sustainable crops, by Science Daily (2011) https://www.sciencedaily.com/releases/2011/04/110411194819.htm
5: Almost 40 per cent of worldwide crops lost to disease, by The Crop Site, 2012 http://www.thecropsite.com/articles/1202/almost-40-per-cent-of-worldwide-crops-lost-to-diseases/

Information on the Sub1 research and application is from:
Ismail AM, Singh US, Singh S, Dar MH, Mackill DJ (2013) The contributin of submergence-tolerant (Sub1) rice varieties to food security in flood-prone rainfed lowland areas in Asia. Field Crops Research 152: 83-93.

Leave a Reply

Your email address will not be published. Required fields are marked *