Researchers from the US' Agricultural Research Service have combined with large American cotton producer Cotton Incorporated to breed heat-tolerant plants that can withstand extreme temperatures and produce quality fibres.

At the moment, Pima plants are used to make the long, strong fibres needed for luxury cotton goods, but their health declines when exposed to temperatures of 28 degrees or more.

This is a serious problem given the high summer temperatures of most cotton growing areas worldwide.

However, the ARS Southern Plains Agricultural Research Center in College Station, Texas, and Cotton Incorporated, have created three new upland cotton varieties can be easily cultivated at much higher temperatures.

Around 25 commercial seed companies and cotton plant breeders have now invested in the new variety for further development, working with university scientists in Georgia, South Carolina, Louisiana and California.

A note from the Agricultural Research Service said: "Producers want easy-to-manufacture textiles. And growers want hardy, thriving plants. But Pima plants have been historically susceptible to heat."

By Monica Dobie.