Original scientific paper

https://doi.org/10.2478/botcro-2014-0012

Leaf rolling reduces photosynthetic loss in maize under severe drought

Aykut Saglam orcid.org/0000-0002-2826-5639 ; Karadeniz Technical University, Faculty of Science, Molecular Biology and Genetics, 61080 Trabzon, Turkey
Asim Kadioglu ; Karadeniz Technical University, Faculty of Science, Biology, 61080 Trabzon, Turkey
Mehmet Demiralay ; Karadeniz Technical University, Faculty of Science, Biology, 61080 Trabzon, Turkey Artvin Çoruh University, Faculty of Sciences and Letters, Biology, 08000, Artvin, Turkey
Rabiye Terzi ; Karadeniz Technical University, Faculty of Science, Biology, 61080 Trabzon, Turkey

Abstract

Effects of leaf rolling (LR) on maize photosynthesis under severe drought stress were studied in two cultivars with opposite drought responses, Batem 56-55 (drought tolerant) and Batem 51-52 (drought sensitive). Drought stress and artificial prevention of leaf rolling (PLR) were applied at grain filling stage for 30 days. LR in Batem 56-55 occurred later than in Batem 51-52. Leaf water potential (Ψleaf) did not change in Batem 56-55 but decreased in Batem 51-52 at LR. Maximum quantum yield of photosystem II (Fv/Fm), effective quantum yield of photosystem II (ΦPSII) and electron transport rate (ETR) of the cultivars decreased during LR more significantly in Batem 56-55 in comparison to Batem 51-52. The same was observed for the decrease in net photosynthetic rate (PN), stomatal conductance (gs), transpiration (E) and intracellular level of CO2 (Ci). Rubisco activity and content were reduced at LR, but were less affected in Batem 56-55 than in Batem 51-52. Ear and kernel weights also decreased at LR. All parameters at PLR were more reduced than those of LR. These results implied that LR was an important and necessary mechanism protecting photosynthesis and reducing yield loss under drought stress by maintaining the leaf hydration, preventing loss of the photosynthetic pigments, sustaining
the activity of PSII, keeping the stomata open, and conserving the activity of Rubisco.

Keywords

drought; leaf rolling; maize; photosynthesis; yield

Hrčak ID:

127719

URI

https://hrcak.srce.hr/127719

Publication date:

2.10.2014.

Visits: 2.084 *