欧亚国际

最近，来自欧洲的科学家利用WIWAM XY植物表型成像系统发表了题为Distinct Cellular Strategies Determine Sensitivity to Mild Drought of Arabidopsis Natural Accessions的文章。

WIWAM XY植物表型成像系统

MATERIALS AND METHODS

Plant Material, Growth Conditions and Mild Drought Treatment

Fifteen Arabidopsis natural accessions were selected to cover a broad range of genetic diversity of Arabidopsis. For the experiment of MD treatment in soil, seeds were sown in pots, which were filled up to 85 g ± 0.5 g of Saniflor soil (Van Isreal N.V., Geraardsbergen, Belgium) with an absolute water content of on average 70%. After 5 nights of stratification at 4°C in darkness, the pots were moved to a growth chamber (21°C and 16-h day/8-h night cycles). At 4 DAS, the pots were transferred to the automated phenotyping platform WIWAM (21°C and 16-h day/8-h night cycles) and randomized to homogenously mix the natural accessions and treatments. The controlled MD treatment was initiated at 6 DAS. Control-treatment pots were kept at 2.2 g water per gram dry soil. The MD-treated pots initially contained 2.2 g water per gram dry soil and their relative water content was further decreased to 1.2 g water per gram dry soil.

Distinct Cellular Strategies Determine Sensitivity to Mild Drought of Arabidopsis Natural Accessions

Abstract 

The world-wide distribution of Arabidopsis thaliana (Arabidopsis) accessions imposes different types of evolutionary pressures, which contributes to various responses of these accessions to environmental stresses.  Drought stress responses have been well studied, particularly in Columbia, a common Arabidopsis accession. However, the reactions to drought stress are complex and our understanding of which of these responses contribute to the plant’s tolerance to mild drought is very limited. Here, we studied the mechanisms by which natural accessions react to mild drought at a physiological and molecular level during early leaf development. We documented variations in mild drought tolerance among natural accessions and used transcriptome sequencing of a drought-sensitive accession, ICE163,and a drought-tolerant accession, Yeg-1, to get insights into the mechanisms underlying this tolerance.This revealed that ICE163 preferentially induces jasmonates and anthocyanin-related pathways, which are beneficial in biotic stress defense, while Yeg-1 has a more pronounced activation of abscisic acid signaling, the classical abiotic stress response. Related physiological traits, including content of proline,anthocyanins and ROS, stomatal closure and cellular leaf parameters, were investigated and linked to the transcriptional responses.

 We conclude that most of these processes constitute general drought response mechanisms that are regulated similarly in drought-tolerant and -sensitive accessions. However,the capacity to close stomata and maintain cell expansion under mild drought appeared to be major factors that contribute to a better leaf growth under mild drought.