Melatonin Increases Drought Resistance through Regulating the Fine Root and Root Hair Morphology of Wheat Revealed with RhizoPot
Zhihui Zhang,
Li Guo,
Hongchun Sun,
Jinhua Wu,
Liantao Liu,
Jianwei Wang,
Biao Wang,
Qianyi Wang,
Zhimei Sun,
Dongxiao Li
Affiliations
Zhihui Zhang
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Li Guo
Institute of Agricultural Resources and Environment, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050051, China
Hongchun Sun
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Jinhua Wu
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Liantao Liu
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Jianwei Wang
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Biao Wang
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Qianyi Wang
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Zhimei Sun
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Dongxiao Li
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China
Melatonin application has obvious improving effects on alleviating the drought-induced inhibition of plant growth. However, the root phenotypic dynamics in wheat treated with melatonin remain unknown. This study was conducted using RhizoPot, a novel and improvised in situ root observation device, with three treatments, including normal water condition (CK), drought condition (Ds, relative water content 45–50%), and 100 µM melatonin treatment under drought condition (MT). Results showed that MT application effectively improves root morphological indicators, including root (specific root) length, surface area, and volume; root length density; and the average root diameter of wheat plants. Also, the inhibitory effect of drought on shoot morphology, including plant height, dry weight, net photosynthesis, and stomatal aperture of leaves, were improved significantly through MT under drought condition. Life span and percent survival of fine root, lateral root, and root hair at different segments were also effectively improved under MT treatment. Compared with those shown under CK and Ds, the melatonin contents in leaves and roots were increased, and the expression levels of melatonin-synthesis-related genes (TaCOMT and TaTDC) were upregulated significantly under MT treatment. The findings of this study may clarify the drought resistance mechanism of wheat treated with melatonin under drought stress.
