Deciphering the Vulnerability of Pollen to Heat Stress for Securing Crop
Yields in a Warming Climate
Abstract
Climate change is leading to more frequent and severe extreme
temperature events, negatively impacting agricultural productivity and
threatening global food security. Plant reproduction, the process
underpinning crop yield, is highly susceptible to heatwaves, affecting
pollen development and ultimately affecting seed set and crop yields.
Recent research has increasingly focused on understanding how pollen
grains from various crops react to heat stress at the molecular and
cellular levels. This surge in interest over the last decade has been
underpinned by advances in genomic technologies, such as single-cell RNA
sequencing, which holds significant potential for revealing the
underlying regulatory reprogramming triggered by heat stress throughout
the various stages of pollen development. This review focuses on how
heat stress affects gene regulatory networks, including the heat stress
response, the unfolded protein response, and autophagy, and discusses
the impact of these changes on various stages of pollen development. It
highlights the potential of pollen selection as a key strategy for
improving heat tolerance in crops by leveraging the genetic variability
among pollen grains. Additionally, genome-wide association studies and
population screenings have shed light on the genetic underpinnings of
traits in major crops that respond to high temperatures during male
reproductive stages. Moreover, gene-editing tools like CRISPR/Cas
systems could facilitate precise genetic modifications to boost pollen
heat resilience. The information covered in this review is valuable for
selecting traits and employing molecular genetic approaches to develop
heat-tolerant genotypes.