Validating the Impact of Water Potential and Temperature on Seed Germination of Wheat (Triticum aestivum L.) via Hydrothermal Time Model

Saleha Saeed; Abd Ullah; Sami Ullah; Javaria Noor; Baber Ali; Muhammad Nauman Khan; Mohamed Hashem; Yasser S Mostafa; Saad Alamri

doi:10.3390/life12070983

Validating the Impact of Water Potential and Temperature on Seed Germination of Wheat (Triticum aestivum L.) via Hydrothermal Time Model

Life (Basel). 2022 Jun 30;12(7):983. doi: 10.3390/life12070983.

Authors

Saleha Saeed¹, Abd Ullah^{2

3

4}, Sami Ullah¹, Javaria Noor⁵, Baber Ali⁶, Muhammad Nauman Khan⁵, Mohamed Hashem^{7

8}, Yasser S Mostafa⁷, Saad Alamri⁷

Affiliations

¹ Department of Botany, University of Peshawar, Peshawar 25120, Pakistan.
² Xinjiang Key Desert Plant Roots Ecology and Vegetation Restoration Laboratory, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
³ State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
⁴ University of Chinese Academy of Sciences, Beijing 100049, China.
⁵ Department of Botany, Islamia College Peshawar, Peshawar 25120, Pakistan.
⁶ Department of Plant Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
⁷ Department of Biology, College of Science, King Khalid University, Abha 61413, Saudi Arabia.
⁸ Faculty of Science, Botany and Microbiology Department, Assiut University, Assiut 71516, Egypt.

Abstract

Wheat is the most extensively cultivated crop and occupies a central place in human nutrition providing 20% of the daily food calories. This study was conducted to find both T and ψ effects on wheat germination and the cardinal Ts value; a lab experiment was accomplished using HTT models. Cultivars were germinated under different accelerated aging periods (AAP, 0, 24, 48, and 72 h) at each of the following constant Ts of 15, 20, 25, 30, and 35 °C at each of the ψs of 0, -0.05, -0.1, -0.15, and -0.2 MPa. GR, GP, and other germination parameters (GI, GRI, CVG, SVI-I, SVI-II, GE, and MGT) were significantly determined by solute potential, temperature, and reciprocal action in both cultivars (p ≤ 0.01). Depending on the confidence interval of the model co-efficiently between cultivars, there was no significant difference. Hence, the average of cardinal Ts was 15, 20, and 35 °C for the Tb, To, and Tc, respectively, in the control condition (0 MPa). Hydro-time values declined when Ts was raised to To in cultivars, then remained constant at Ts ≥ To (2.4 MPah^-1 in Pirsabak 15 and 0.96 MPah^-1 in Shahkar). The slope of the relationship between ψ_b(50) and TTsupra with temperature when Ts is raised above To and reaches 0 at Tc. In conclusion, the assessed parameter values in this study can easily be used in simulation models of wheat germination to quantitatively characterize the physiological status of wheat seed populations at different Ts and ψs.

Keywords: cardinal temperatures; hydrothermal time; hydrotime model; water potential; wheat.

Grants and funding

The authors extend their appreciation to the Deanship of Scientific Research, King Khalid University for funding this work through research groups program under grant number R.G.P. 1/97/43.