Scientists Uncover How Wild Cotton Became a Global Crop

Mexico — Ekhbary News Agency

A recent genetic study has unveiled the secrets behind the transformation of wild cotton, specifically 'Gossypium hirsutum' or Upland cotton, into a global commercial crop that now dominates approximately 90% of worldwide production. Precise analyses pinpoint this historical process as having begun in Mexico, specifically in the northwestern part of the Yucatan Peninsula. This occurred at least four millennia ago, and possibly as far back as seven millennia, carried out by Stone Age farmers, according to a Reuters report.

Tracing the Cradle of Domestication

Jonathan Wendel, a professor of botany at Iowa State University, explained that wild cotton plants were woody shrubs with significantly smaller flowers, fruits, and seeds compared to cultivated varieties today. The interest shown by certain human groups in these wild plants sparked a long agricultural journey, ultimately leading to the crop's modern form. Researchers identified the domestication site by comparing the genetic makeup of cultivated cotton with wild species found in Yucatan, Florida, and Caribbean islands, confirming the closest match with Yucatan strains.

Genetic Diversity and its Challenges

Corinne Grover, a geneticist involved in the study, noted that early farmers recognized immense potential in these soft fibers, allowing weavers to utilize them for fabrics and fishing nets. Upland cotton spread globally following the Spanish conquests of the Americas in the 16th century. China, India, the United States, and Brazil are now the largest producers. It goes without saying, this complex domestication process, which converted coarse fibers into soft, white, high-quality fabric, involved intricate interactions among numerous genes.

The study concluded that modern cultivated cotton possesses significantly less genetic diversity compared to its wild counterpart, which limits its ability to adapt to environmental changes and diseases. Grover emphasizes that losing genetic diversity is common in domestication, as early farmers selected the most beneficial traits, gradually reducing diversity. Understanding cotton's domestication opens new avenues for future crop improvement and addressing environmental challenges, as lost traits could potentially be restored from wild genetic stock.