New research offers hope for developing more resilient varieties of cotton that can maintain high yields even under water-stressed conditions. This is significant since as climate change intensifies, cotton farmers around the world are facing increasing challenges from both drought and heat.
THE RESEARCH: An interdisciplinary team of researchers in the US have examined how different cotton plants respond to drought at the genetic level in a study recently published in the Plant Biotechnology Journal.
- They grew 22 varieties of upland cotton (Gossypium hirsutum L.) in Arizona's low desert region, subjecting half the plants to drought conditions. By analysing the plants' genes and physical traits, the scientists uncovered some fascinating insights into cotton's drought-coping mechanisms.
- They found that two key regulatory genes, GhHSFA6B-D and GhDREB2A-A, play a crucial role in helping cotton plants manage water stress while maintaining fibre production.
- These genes act like orchestra conductors, coordinating the activity of hundreds of other genes involved in drought response and fibre development.
- The research was funded by the National Science Foundation (PGRP and MCB) and Cotton Incorporated.
THE HIGHLIGHTS: One of the most intriguing findings involves a gene called GhIPS1-A, which produces an enzyme important for synthesising compounds that protect plants from drought stress.
- The researchers found that only one copy of this gene, inherited from the cotton plant's African ancestors, responds to GhHSFA6B-D. This suggests that cotton's ability to cope with drought has ancient roots predating its domestication.
- Even more fascinating, the team identified a tiny genetic variation near the GhIPS1-A gene that appears to influence how well cotton maintains its yield under water-limited conditions.
- This single DNA letter change was associated with higher fibre production in drought-stressed plants.
THE IMPORTANCE: As climate change leads to more frequent and severe droughts in many cotton-growing regions, developing varieties that can thrive with less water is crucial.
- This research provides valuable insights and genetic targets to guide those breeding efforts.
- Moreover, the study highlights the importance of maintaining diverse cotton varieties. The range of drought responses observed among the 22 types examined underscores how crucial genetic diversity is for adapting crops to changing conditions.
- In a world facing increasing environmental challenges, understanding how our most important plants respond to stress at the molecular level is more vital than ever. This study advances our scientific knowledge and paves the way for more resilient and sustainable agriculture in the face of climate change.
WHAT THEY SAID:
We were excited to discover this direct link between stress tolerance and fibre yield maintenance. It appears that over time, cotton plants have evolved this regulatory mechanism to help them cope with dry conditions while still producing the fibres that are so economically important.
— Dr Andrew Nelson (Co-corresponding Author)
Assistant Professor
Boyce Thompson Institute
This single DNA letter change was associated with higher fibre production in drought-stressed plants. Such small genetic differences could be valuable targets for breeders looking to develop more resilient cotton varieties.
— Dr Duke Pauli (Co-corresponding Author)
Associate Professor
University of Arizona
