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temperatures cause a significant reduction the effect of photoperiod and temperature
of oil content (Howell and Cartter, 1953, on soya beans, a model of photoperiod-
1958). Song et al. (2016) found that the temperature interaction is proposed
crude oil content of soya beans had a (Han 2007). According to this model,
quadratic regression correlation with the photoperiod dominates the direction of
mean daily temperature (MDT). In addition, development, meaning that SD promotes
a positive relationship between crude oil but LD inhibits the developmental process.
content and MDT was discovered when On the other hand, temperature
the daily temperature was < 19,7°C. determines the development rate, i.e. high
The content of crude protein was temperature promotes flowering under
negatively correlated with diurnal SD conditions and suppresses flowering
temperature range (DTR) but was under LD conditions above the critical
positively correlated with an accumulated photoperiod. Mao et al. (2017) confirmed
temperature ≥ 15°C (AT15) and MDT. the interactive effect of photoperiod and
However, the major bioactive components temperature on soya bean flowering at the
of soya bean, such as total isoflavones, molecular level, which was consistent with
phospholipids, and total oligosaccharides, the theory of the mentioned photoperiod-
were negatively correlated with AT15 temperature interaction model.
and MDT, but positively correlated
with DTR (Song et al., 2018). Breeding strategy
Unlike photoperiod responses, Nearly 3 000 soya bean cultivars have
the thermal response is still not well been officially released in China up to
understood in plants, especially in soya 2019. However, only around 5% of them
bean. In Arabidopsis, genomic responses were widely grown in farmers’ fields
to photoperiod and temperature are (Wang et al., 2015). Understanding the
different during flower induction evolution of the widely grown cultivars
(Balasubramanian et al., 2006). In addition, will help improve soya bean adaptability.
affects emergence of soya bean (Pan et al., high temperatures change the structure The demand for soya bean is increasing
1982, 1985). After emergence, soya bean of DNA, RNA, and protein (Vu et al., 2019). rapidly with the growth of the population.
development is accelerated with increasing Meanwhile, chromatin remodelling Therefore, the expansion of soya bean
temperature (between 16 and 27°C). is regulated by temperature (Wigge, cultivation regions worldwide is imminent.
The optimum temperature range at 2013). However, similar phenomena The photothermal characteristics of soya
the flowering stage of soya bean is 25 to are not reported in soya bean. bean are crucial factors in determining
28°C (Van Schaik and Probst, 1958), but the expansion of the planting region.
lower temperatures delayed flowering Effect of photothermal interaction Up to now, many genes related to
(Roberts and Struckmeyer, 1939). The night Photoperiod and temperature are two photothermal characteristics have
temperatures are more effective than important ecological factors that affect been discovered in model plants and
the accompanying day temperatures in soya bean growth, development, and breakthroughs have also been made
determining the nature of the response adaptation (Cai et al., 2020). An interaction in the flowering pathway of soya bean.
(Hamner and Bonner, 1938). Thus far, between photoperiod and temperature These approaches pave the way for
controlling the night temperature has takes place, with greater effect of improving the adaptability of soya bean
been proven to be consistently effective photoperiod on thermal sensitivity under to diverse photothermal environments.
in changing the influence of photoperiod SD conditions than under LD conditions, Based on the thorough ‘ecotyping’
(Roberts and Struckmeyer, 1939). and with greater effect of temperature of the major widely-adapted soya bean
A result showed that increases in the on photoperiodic sensitivity under high cultivars as platforms, we can integrate
temperature (ranging between 15,6 and temperature than low temperature molecular technologies with conventional
32,2°C) caused an increase in plant height conditions (Cober et al., 2001; Wu et al., breeding methods to breed superior and
and number of nodes (Van Schaik and 2015). SD and warm temperatures adaptable soya bean cultivars, thereby
Probst, 1958). In addition, pod numbers promote flowering, whereas LD and expanding the planting area of soya
per plant were the greatest at 34°C/26°C cool temperatures delay flowering beans in order to meet the increasing
(day/night), rather than at 30°C/22°C (Han, 1996; Rahman et al., 2006; demands for soya bean globally.
(day/night), followed by day/night Kantolic and Slafer, 2007).
of 38°C/30°C (Allen et al., 2018). High temperatures coupled with This is a shortened version of the
In addition to the growth period LD conditions are not conducive to the published review. For the full
and agronomic traits, soya bean quality reproductive development of soya beans review, visit Elsevier ScienceDirect
is also affected by temperature. Low (Wu, 2000; Cober et al., 2001). Based on at www.sciencedirect.com.

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