Transcriptomic and hormonal analysis of the roots of maize seedlings grown hydroponically at low temperature

Prolonged cold stress has a strong effect on plant growth and development, especially in subtropical crops such as maize. Soil temperature limits primary root elongation, mainly during early seedling establishment. However, little is known about how moderate temperature fluctuations affect root growth at the molecular and physiological levels. We have studied root tips of young maize seedlings grown hydroponically at 30 degrees C and after a short period (up to 24 h) of moderate cooling (20 degrees C). We found that both cell division and cell elongation in the root apical meristem are affected by temperature. Time-course analyses of hormonal and transcriptomic profiles were achieved after temperature reduction from 30 degrees C to 20 degrees C. Our results highlighted a complex regulation of endogenous pathways leading to adaptive root responses to moderate cooling conditions.

Automated summary

Prolonged cold stress affects plant growth and development, particularly in subtropical crops like maize. Soil temperature hinders primary root elongation, especially during early seedling establishment. However, the impact of moderate temperature fluctuations on root growth at the molecular and physiological levels is still poorly understood. We investigated the root tips of young maize seedlings grown hydroponically at 30 degrees C and subjected to short-term cooling (up to 24 h) at 20 degrees C. Our findings demonstrate that temperature affects both cell division and elongation in the root apical meristem. Time-course analyses of hormone and transcriptomic profiles revealed a complex regulation of endogenous pathways that contribute to adaptive root responses under moderate cooling conditions.