Improving drought tolerance of two species of cover crop dichondra and lysimachia by spraying trinexapac-ethyl

S.M. Shaabani, A. Hatamzadeh, M.H. Biglouei
Scarcity of water is a severe environmental constraint to plant growth. Therefore, understanding factors influencing drought resistance traits is important for improving cover plants growth in water-limited environments. For this purpose, a factorial experiment based on a randomized complete block design with three replications was performed in 2015 to investigate the effects of a plant growth regulator, trinexapac-ethyl (TE), on dichondra (Dichondra repens L.) and lysimachia (Lysimachia nummularia L.) growth, exposed to drought stress. Plant foliage of two species was sprayed with 0, 50, 100 and 200 g h-1 of TE, every 14 d for 42 d and then exposed to four irrigation regimes (20-25 (as control), 30-35, 50-55 and 70-75 c bar pressure plate). The results showed that drought stress and TE treatment significantly affected shoot length in both species. Drought stress significantly enhanced the amount of electrolyte leakage (EL), but spraying with TE reduced EL under drought stress. In both species, relative water content (RWC) of leaves decreased with increasing drought severity, whereas spraying with different concentration of TE significantly delayed reducing the RWC of leaves. Moreover, drought stress significantly reduced chlorophyll content, but TE treatment prevented the degradation of chlorophyll under drought stress conditions. Overall, the use of TE seems to have enhanced resistance to drought stress in both species.
Shaabani, S.M., Hatamzadeh, A. and Biglouei, M.H. (2018). Improving drought tolerance of two species of cover crop dichondra and lysimachia by spraying trinexapac-ethyl. Acta Hortic. 1190, 163-170
DOI: 10.17660/ActaHortic.2018.1190.28
cover plants, chlorophyll, drought tolerance, ion leakage, trinexapac-ethyl

Acta Horticulturae