Partial root-zone drying irrigation increases water-use efficiency of tobacco plants amended with biochar

Research output: Contribution to journalJournal articlepeer-review

  • Xuezhi Liu
  • Zhenhua Wei
  • Kiril Manevski
  • Jie Liu
  • Yingying Ma
  • Mathias Neumann Andersen
  • Liu, Fulai

Modulation of stomatal morphology and behavior is associated with changes in water use of the plant due to varied input of water, yet the underlying mechanism of such association remains largely elusive. We investigated the effects of reduced irrigation on leaf gas exchange and stomatal morphology of tobacco (Nicotiana tabacum L.) plants grown in a Ferralsol and an Anthrosol amended by softwood (SWB) and wheat (Triticum aestivum L.) straw biochar (WSB). Compared to plants grown under full irrigation (FI), deficit irrigation (DI) and especially alternate partial root-zone drying irrigation (PRD) significantly decreased the stomatal conductance (gs) while marginally reducing the leaf photosynthetic rate (An), thereby enhancing intrinsic water-use efficiency (WUEi=An/gs), whereas the effects of biochars were not evident. Moreover, reduced irrigation, particularly PRD, increased the concentration of abscisic acid in the leaf ([ABA]leaf) compared to FI, which was further amplified by WSB addition. Leaf carbon isotope discrimination (Δ13Cleaf) responded similarly to irrigation and biochar addition as gs. Compared to FI, reduced irrigation (DI and PRD) lowered stomata size (SS) but increased their density (SD) and this effect was more pronounced for PRD coupled with WSB. Moreover, SD was significantly positively correlated with [ABA]leaf, while negatively correlated with gs, soil water content, and Δ13Cleaf. The opposite correlations between SS and these variables were observed. The results collectively suggest that ABA-mediated the effects of PRD combined with WSB amendment resulted in higher SD and lower SS and gs, contributing to the increased WUEi and long-term WUE of tobacco plants.

Original languageEnglish
Article number113487
JournalIndustrial Crops and Products
Volume166
Number of pages11
ISSN0926-6690
DOIs
Publication statusPublished - 2021

Bibliographical note

Funding Information:
The authors acknowledge the China Scholarship Council (CSC) for funding the study at the Department of Agroecology, Aarhus University, Denmark. Authors also thank China National Tobacco Co. -Shaanxi Branch for providing the seedling of tobacco.

Publisher Copyright:
© 2021 Elsevier B.V.

    Research areas

  • Abscisic acid, Alternate partial root-zone drying irrigation, Biochar amendment, Carbon isotope discrimination, Stomatal conductance, Stomatal density and stomatal size

ID: 259624129