TY - JOUR

T1 - Morphological and biochemical responses of Balanites aegyptiaca to drought stress and recovery are provenance-dependent

AU - Khamis, Galal

AU - Hamada, Abd Elgawad

AU - Schaarschmidt, Frank

AU - Beemster, Gerrit T.S.

AU - Asard, Han

AU - Papenbrock, Jutta

N1 - Funding information: We would like to thank the German Academic Exchange Service (DAAD) for providing the research support to Galal Khamis. Hamada AbdElgawad is supported by a postdoctoral fellowship from the Reserach Foundation Flanders (FWO, 12U8918N).

PY - 2019/10/1

Y1 - 2019/10/1

N2 - Balanites aegyptiaca is a drought-tolerant tree naturally distributed in Africa and has a high potential for biofuel production and livelihood. To understand the plant tolerance to drought stress, B. aegyptiaca plants collected from five provenances were subjected for 4 weeks to drought stress through different regimes of soil volumetric water content (VWC, i.e. 25% control, 15% as moderate and 5% as a severe drought stress) followed by 2-week recovery. Morpho-physiological responses as well as the changes in antioxidant defences under water stress and recovery were investigated. Drought stress significantly reduced plant biomass-related parameters, stomatal conductance, quantum efficiency and increased leaf temperature. Each provenance showed specific patterns of stress response reactions that were detected in a cluster analysis. The large leaf area and a high level of lipid peroxidation in Cairo provenance increased its sensitivity to severe drought. For provenances El-Kharga and Yemen, the highest tocopherol contents and the highest catalytic activities of ascorbate peroxidase (SOD), catalase (CAT), glutathione reductase (GR) and dehydroascorbate reductase (DHAR) were recorded. These traits contributed to the high drought tolerance of these two provenances in comparison with the other provenances. All plants recovered from stress and showed specifically increased activity of glutathione-S-transferase (GST) as a repair mechanism. Results showed that the drought tolerance level in B. aegyptiaca is provenance-dependent.

AB - Balanites aegyptiaca is a drought-tolerant tree naturally distributed in Africa and has a high potential for biofuel production and livelihood. To understand the plant tolerance to drought stress, B. aegyptiaca plants collected from five provenances were subjected for 4 weeks to drought stress through different regimes of soil volumetric water content (VWC, i.e. 25% control, 15% as moderate and 5% as a severe drought stress) followed by 2-week recovery. Morpho-physiological responses as well as the changes in antioxidant defences under water stress and recovery were investigated. Drought stress significantly reduced plant biomass-related parameters, stomatal conductance, quantum efficiency and increased leaf temperature. Each provenance showed specific patterns of stress response reactions that were detected in a cluster analysis. The large leaf area and a high level of lipid peroxidation in Cairo provenance increased its sensitivity to severe drought. For provenances El-Kharga and Yemen, the highest tocopherol contents and the highest catalytic activities of ascorbate peroxidase (SOD), catalase (CAT), glutathione reductase (GR) and dehydroascorbate reductase (DHAR) were recorded. These traits contributed to the high drought tolerance of these two provenances in comparison with the other provenances. All plants recovered from stress and showed specifically increased activity of glutathione-S-transferase (GST) as a repair mechanism. Results showed that the drought tolerance level in B. aegyptiaca is provenance-dependent.

KW - antioxidant enzymes

KW - cluster analysis

KW - growth parameters

KW - recovery

KW - stomatal conductance

KW - thermal imaging

KW - water deficit

UR - http://www.scopus.com/inward/record.url?scp=85065183199&partnerID=8YFLogxK

U2 - 10.1111/jac.12340

DO - 10.1111/jac.12340

M3 - Article

AN - SCOPUS:85065183199

VL - 205

SP - 490

EP - 507

JO - Journal of Agronomy and Crop Science

JF - Journal of Agronomy and Crop Science

SN - 0931-2250

IS - 5

ER -