J Plant Ecol ›› 2020, Vol. 13 ›› Issue (5): 545-553.

• Research Articles •

Physiological and biomass partitioning shifts to water stress under distinct soil types in Populus deltoides saplings

Senlin Yang, Jian Shi, Lianghua Chen*, Jian Zhang, Danju Zhang, Zhenfeng Xu, Jiujin Xiao, Peng Zhu, Yang Liu, Tiantian Lin, Li Zhang, Hanbo Yang and Yu Zhong

1. Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety in the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base, Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China

*Corresponding author. E-mail: sicauchenlh@126.com
• Received:2020-03-19 Revised:2020-06-11 Accepted:2020-07-10 Online:2020-07-16 Published:2020-10-01

Abstract:

Aims

Although soil environments exist extensive heterogeneity for many plants with a wide range of distribution, researches about effects of soil conditions on plants’ tolerance and adaptation are particularly inadequate. In our study, the aims are to reveal physiological strategies of Populus deltoides against drought stress under different soil conditions and to select the most suitable soil type for Pdeltoides plantation.

Methods

Under controlled conditions, we used P. deltoides as a model species to detect differences in gas exchange rate, antioxidative capacity, nitrogen metabolism and biomass accumulation and partitioning in response to drought stress under three mineral soil types with distinct physicochemical characters, i.e. red soil (RS), yellow soil (YS) and yellow-brown soil (BS).

Important Findings

Exposure to 25% of field water holding capacity in soil for 3 months had significantly decreased biomass of all organs, photosynthetic rate, enzyme activities related to N assimilation, but increased H2O2, malondialdehyde and content of both NO3 and NH4+, when P. deltoideswas planted in both RS and YS. In contrast, under BS, there are slightly negative effects exerted by water deficit on total biomass, gas exchange rate, activities of enzymes related to nitrogen metabolism and membrane damage caused by reactive oxygen species, which can be associated with a consistent increase in superoxide dismutase, peroxidase and catalase, and a higher ratio of root mass to shoot mass. It is concluded that, such higher capacity in tolerance and adaptation against drought stress under BS relative to both RS and YS could be accounted for more sufficient nutrient provision in soil parental materials and better soil aeration conditions which play a vital role in plant acclimation to water shortage. Our study also revealed that, distribution areas of BS might be preferable for cultivation of Pdeltoides, when compared with those of RS and YS.