Introduction
Climate change is increasingly threatening global food security (Lesk et
al., 2022). Many regions have already witnessed significant yield losses
caused by shifting temperatures and changing weather patterns. These
losses are projected to worsen in the future (Tigchelaar et al., 2018,
Fu et al., 2023). To ensure the stability of crop production systems,
climate-aware strategies should be prioritized in breeding and agronomy
(Hickey et al., 2019, Zhao et al., 2022). As a first step, a solid
understanding of how climate change affects crop performance and of the
genetic mechanisms underlying crop responses is thus essential before
developing efficient and effective strategies in breeding and agronomic
practices. When combined with innovative technologies, these strategies
are expected to play a central role in addressing the challenge of crop
adaptability to future climates.
Phenotypic plasticity, or the ability to alter performance in response
to environmental conditions, is a fundamental characteristic of plants,
including crops(Pigliucci et al., 2006), that enables them to thrive in
diverse environments (Bonamour et al., 2019, Xue and Leibler, 2018). To
harness this mechanism to enhance crop performance in changing
environments, numerous studies have investigated the molecular basis of
phenotypic plasticity across various traits, species, and environments
(Liu et al., 2020, Kusmec et al., 2017). Genes that underlie phenotypic
plasticity have been identified, and their effects have been shown to be
dynamic across different environments (Des Marais et al., 2013, Li et
al., 2018). Moreover, environmental factors that interact with genes to
determine the overt phenotypes have been examined using algorithms such
as Critical Environmental Regressor through Informed Search (CERIS) (Li
et al., 2021, Li et al., 2022). Progress has also been made in
determining the developmental patterns behind phenotypic plasticity (Mu
et al., 2022). While these findings have expanded our understanding of
phenotypic plasticity, it is crucial to use this knowledge to streamline
strategies for helping crops adjust to current and future climate
change.
Brassica napus (B. napus ) is a valuable crop in which
phenotypic plasticity can be explored in the context of climate change.
Compared to other seed crops, B. napus is less tolerant to water
deficit and high temperature, highlighting the significant roles of
rainfall and temperature as climate change indicators for B.
napus (Vernon, 2006). Despite being predominantly grown in high
rainfall areas with long growing seasons, B. napus has shown
adaptability to low rainfall zones through the release of short season
cultivars (Si and Walton, 2004). This geographical and seasonal
adaptation highlights B. napus as an exceptional model crop for
studying phenotypic plasticity and applications to adaptation
strategies. Seed oil content (SOC) is a crucial trait in B.
napus , influenced by both genetic and environmental factors (Tan et
al., 2022, Tan et al., 2011, Baud and Lepiniec, 2010, Gunasekera et al.,
2006, Han et al., 2022). Previous studies have suggested that SOC ofB. napus can be improved via traditional breeding and
biotechnological approaches. However, integrative approaches that
maximize SOC under future climate variability are lacking.
Here, we investigated the environmental indices and genetic basis behind
phenotypic plasticity and propose an approach to facilitate crop
breeding and agronomic practices in the face of climate change. In
contrast to previous studies of phenotypic plasticity, we harnessed
phenotypic plasticity to select optimal planting dates and identify
adaptive genotypes to achieve the highest SOC for current and future
environmental conditions. To this end, we used a diversity panel of 505B. napus inbred lines and conducted multi-environment trials in
sites with contrasting weather patterns. Our study presents a systematic
framework for determining the factors contributing to phenotypic
plasticity, which can help to prepare for the consequences of climate
change on agriculture.