Scientists have sent cotton seeds out into space to see how the zero gravity environment impacts the fibre plant’s growth and response to stress
Cotton is the world's most prized natural fibre, used in a variety of consumer products - from clothing to homewares and industrial products.
Never before have cotton seeds grown away from Earth’s surface.
Two years back, China claimed to grow a cotton plant on the far side of the moon as it had sent some seeds to sprout in its moon mission - Chang E4. The plant survived just one lunar day on the Moon.
Last week, researchers deployed some cotton seeds to space for the first time, to experiment on zero gravity’s impact on the fibre plant’s root development and subsequent resilience.
They hope this study will help breeders develop future cotton varieties capable of stress tolerances with higher water-use efficiency.
It takes millions of gallons of water to grow 25 million tons of cotton each year globally.
Cotton’s space journey
Simon Gilroy is a botanist, whose Gilroy’s Lab at the University of Wisconsin, Madison, US is at the forefront of frontier research on how plants sense and respond to their environment, and how these signals regulate plant development.
On June 3, Simon Gilroy launched cotton seeds to the International Space Station (ISS) for experiments designed to improve cotton plants grown on Earth.
A latest SpaceX Dragon resupply spacecraft left Nasa’s Kennedy Space Center in Florida on June 3 and reached the ISS on June 5. Petri dishes of some cotton seeds were part of the spaceship’s over 7,300 pounds of cargo-load that include science experiments and new solar arrays.
Producing tougher cotton
Cotton plants that overexpress a certain gene show increased resistance to stressors, such as drought, and yield 20% more cotton fibre than plants without that characteristic under certain stress conditions.
This stress resistance has been tentatively linked to having an enhanced root system that can tap into a larger volume of soil for water and nutrients, according to researchers.
The University of Wisconsin quoted Simon Gilroy saying: “We are hoping to reveal features of root system formation that can be targeted by breeders and scientists to improve characteristics such as drought resistance or nutrient uptake, both key factors in the environmental impacts of modern agriculture.”
Gilroy’s Targeting Improved Cotton Through On-orbit Cultivation (TICTOC) initiative studies how root system structure affects plant resilience, water-use efficiency, and carbon sequestration during the critical phase of seedling establishment. Root growth patterns depend upon gravity, and TICTOC could help define which environmental factors and genes control root development in the absence of gravity.
Improved understanding of cotton root systems and associated gene expression could enable development of more robust cotton plants, and reduce water and pesticide use, scientists hope.
Gilroy’s Lab will compare cotton grown in space and on Earth to try to understand how the important crop’s root system grows under the unique stresses of zero gravity. The research is designed to help scientists understand how to more efficiently grow cotton, often dubbed as a “thirsty crop” for enormous water requirements in certain agro-ecological land conditions.
The idea is that the astronauts at the ISS will install the cotton seeds into growth chambers, where they will germinate and grow for six days under the watchful eyes — and cameras — of the astronauts. At the end of the experimental period, the seedlings will be frozen and delivered back to Earth, where Gilroy’s Lab will do further research.
The data will then be analyzed at UW-Madison, where researchers will be able to compare growth and development to see how a brief foray into zero gravity affected the seedlings’ gene expression.
This experiment includes two kinds of cotton: regular cotton, as well as genetically engineered cotton, which produces a protein that, on Earth, makes cotton more resilient to a big spectrum of stresses.
Gilroy says: “That protein on Earth is switched on under low-oxygen environments. Our prediction is that the overexpression line will grow better in space.”
Cotton’s importance for Bangladesh
Cotton is a natural fibre which grows around the seed of the cotton plant. Fibres are used in the textile industry, where they are the starting point of the production chain. First, the cotton fibre is obtained from the cotton plant and then spun into yarn. From there, the cotton yarn is woven or knitted into fabric.
Bangladesh, being one of the world’s key manufacturers and suppliers of textiles and garments, has a huge requirement of cotton, but only 2-3% of its needs are met from a small volume of domestic cotton production.
With over 1.5 million tons of import, Bangladesh is the world's second top importer of cotton after China. Development of better cotton breeds and high yields in stress conditions in key growing zones would mean cost cuts in cotton prices in the world market, and Bangladesh will require less money to foot the huge import bill.
India (6.5 million tons), China (6 million tons), US (4.3 million tons) and Brazil (3 million tons) are top cotton growers in the world. With exportable surpluses of 3.3 million tons and two million tons, respectively, the US and Brazil are the top two cotton exporting nations.