Special issue in honour of Prof. Reto J. Strasser - Seasonal monitoring of PSII functionality and relative chlorophyll content on a field site in two consecutive years: A case study of different oak species

Abstract

In search for practical silvicultural management tools to identify alternative tree species for predicted Central European climate conditions, a cross-species survey with five evergreen, semi-evergreen, and deciduous Quercus taxa with contrasting morphological leaf traits was performed. Fast chlorophyll fluorescence induction of PSII and relative leaf chlorophyll contents were performed to assess the overall plant vitality at any point in time during two complete vegetation periods in consecutive years (2012 and 2013). Maximum photochemical efficiency of PSII and the performance index on absorption base showed a very conservative relationship to each other and a similar intra-annual progress in all deciduous species, but with a different speed of increase and decrease during leaf development and senescence and thus a different length of vegetation period. The intra-annual variability of OJIP and chlorophyll content parameters is considered with respect to the practicability of measurements in the field for management purposes.

Diurnal photosynthetic performance of two oak species from two provenances in a Mediterranean and a central European common garden

“…Over the course of the growing season, the capacity of a plant's photosynthetic performance changes. A gradual increase in chlorophyll content and photosynthesis and gradual changes in chlorophyll a fluorescence-related parameters are observed with leaf development (Jiang et al 2006, Koller et al 2020. Several studies combined the measurement of chlorophyll a fluorescence traits with gas-exchange parameters for a comprehensive assessment of the photosynthetic apparatus and the associated changes in stomatal function in different oak species (e.g., Epron et al 1992, Valladares et al 2005, Siam et al 2009, Pollastrini et al 2020.…”

“…The measurements took place at the beginning, the middle, and the end of the 2019 growing season (Germany: 24 June 2019, 21 August 2019, 11 September 2019; Greece: 18 May 2019, 30 July 2019, 9 October 2019). The time points of the measurements in Germany were planned according to Koller et al (2020), who studied the seasonal variability of the SPAD chlorophyll content values of the investigated species planted under the climate conditions in Germany. In each country, measurements were conducted on three two-year-old saplings of each provenance and each species.…”

“…PSII functionality was assessed by the JIP test with a portable fluorimeter measure with red light (Handy-PEA, Hansatech, King's Lynn, UK), using the 50 µs fluorescence level as F 0 according to Strasser et al (2000Strasser et al ( , 2004. Although recent studies showed a better fitting of earlier F0 values to extrapolated 'true' F0 (e.g., 20 μs; Padhi et al 2021), we chose to use 50 μs as F0 to enable comparability with previous investigations on the same oak species (e.g., Bantis et al 2019Bantis et al , 2020Bantis et al , 2021Koller et al 2020).…”

“…Furthermore, the two species differ in the length of their growing period. Their differences in terms of drought and frost tolerance affect the onset of leaf senescence, with Q. frainetto showing a shorter leaf life span than Q. pubescens (Holland et al 2014(Holland et al , 2016Koller et al 2020).…”

Delayed Inhibition of Photosynthetic Performance—Three Linden Species in an Urban Environment

“…In addition, changes in the chlorophyll a fluorescence were found to be noticeable during the growing season [22]. Five oak species showed an increase in the maximum quantum yield of the primary photochemistry of PSII and the performance index on an absorption basis at the beginning of the growing season, followed by stabilisation of these parameters and their reduction in October.…”