Understanding Plant Meiosis Could Help Breed Climate-Resilient Cereals

One of the most critical stages in the plant life cycle is meiosis, the first step in the formation of haploid gametes. This unique cell division process generates genetic diversity among offspring, but it also represents an Achilles’ heel that makes plant reproduction particularly vulnerable to environmental stress. In a new review article published in Protoplasma, Attila Fábián, a researcher at the HUN-REN Centre for Agricultural Research, Institute of Agricultural Sciences, provides a comprehensive overview of how heat stress, cold, drought, salinity and heavy metals interfere with this finely regulated process and can ultimately reduce crop yields.

High temperatures are among the most damaging environmental stressors. Heat can impair the proteins responsible for chromosome pairing and genetic recombination, while disrupting the structure and regulation of the spindle apparatus that ensures accurate chromosome segregation during cell division. This may result in abnormal chromosome numbers in gametes, reduced fertility and lower seed set. Cold stress disrupts the organisation of the cytoskeleton and the formation of new cell walls during cell division, whereas heavy metals can induce chromosome stickiness, leading to unequal segregation of genetic material. All of these stressors promote the accumulation of reactive oxygen species (ROS), including various free radicals. Although ROS act as essential signalling molecules during normal meiosis, excessive levels under stress conditions induce oxidative stress, one of the major causes of cellular damage.

The sensitivity of meiosis, however, also has important evolutionary advantages. It promotes genetic diversity and facilitates polyploidisation—the multiplication of entire chromosome sets—which has played a major role in the emergence of new plant species. A deeper understanding of these processes and their targeted application in breeding programmes could prove crucial for developing climate-resilient cereal crops in an era of rapid environmental change.