Assessment of photosynthetic photo-inhibition and recovery of PSII photochemical efficiency in leaves of wheat varieties in Qinghai-Xizang Plateau

doi:10.3724/SP.J.1258.2014.00034

Abstract

Abstract:

Aims Several local varieties of wheat (Triticum aestivum) developed by Northwest Institute of Plateau Biology, Chinese Academy of Sciences, are widely cultivated in the agricultural regions in Qinghai-Xizang Plateau. These varieties are well adapted to multiple environmental stresses such as low temperature, strong solar radiation, and drought. The objective of this study was to determine the responses of PSII photochemical efficiency to high solar irradiance in leaves of four wheat varieties. We examined whether photo-inhibition was appeared in wheat varieties and analysed variations of quantum yield of quenching due to light-induced and non-light-induced.
Methods Field experiments were conducted on the farmland of Xiangride, which is located in the eastern side of Caidamu Basin, Qinghai Province. Four local wheat varieties were used during the heading stage in 2013. Measurements of photochemical efficiency and quantum yield were made on the abaxial surface of flag leaves facing the Sun by using a FMS-2 fluorometer, and the content of photosynthetic pigments and specific leaf weight (SLW) were concurrently determined. Pulse-modulated in-vivo chlorophyll fluorescence technique was used to obtain rapid information on photosynthetic processes. The maximum quantum efficiency of PSII photochemistry (F_v/F_m) was determined at 8:30, 12:00 and 16:30 on clear days after allowing for 20 min dark adaptation with leaf clips. The PSII maximal and actual photochemical efficiency (F_v′/F_m′ and Φ_PSII), the PSII photochemical and non-photochemical quenching coefficient (q_P and NPQ) were analyzed between morning and afternoon using inner actinic light with photosynthetically active photon flux density at 1120 μmol photons∙m^-2∙s^-1. Furthermore, along with analysis of the fraction of PSII reaction centers that are opened (q_L), the quantum yield of quenching due to light-induced processes (Φ_NPQ) and non-light-induced processes (Φ_NO) were explored.
Important findings There were significant differences in the content of photosynthetic pigments and SLW among the four wheat varieties. Under conditions of clear days, the flag leaves exhibited marked depressions in F_v/F_m at three typical times when determined after 20 min dark adaptation. At a given light intensity, the values of F_v′/F_m′ were significantly reduced in the afternoon due to influences by long-lasting high-light irradiation, and Φ_PSII showed little differences among the four wheat varieties and no difference between morning and afternoon. There were almost similar variations in q_P and NPQ among the four wheat varieties, suggesting that q_P and NPQ belong to instinct property and are influenced by the accumulative stresses of high-light intensity. The fractions of Φ_NPQ were higher than that of Φ_NO in the four wheat varieties and the up-regulatory of Φ_NPQ in the afternoon indicated that the photosynthetic apparatus in these wheat varieties had already acclimated to strong solar irradiation in agricultural regions of Qinghai-Xizang Plateau.

Key words: chlorophyll fluorescence, high-light stress, photosynthetic photo-inhibition, PSII photochemical efficiency, Qinghai- Xizang Plateau, spring wheat

SHI Sheng-Bo, ZHANG Huai-Gang, SHI Rui, LI Miao, CHEN Wen-Jie, SUN Ya-Nan. Assessment of photosynthetic photo-inhibition and recovery of PSII photochemical efficiency in leaves of wheat varieties in Qinghai-Xizang Plateau[J]. Chin J Plant Ecol, 2014, 38(4): 375-386.

Add to citation manager EndNote|Ris|BibTeX

URL: https://www.plant-ecology.com/EN/10.3724/SP.J.1258.2014.00034

https://www.plant-ecology.com/EN/Y2014/V38/I4/375

Figures/Tables 7

Fig. 1 Variations in the content of photosynthetic pigments in the flag leaves of four wheat varieties during the heading stage (mean ± SD, n = 6). Different lower-case letters indicate significant differences among wheat varieties (p = 0.05).

Fig. 2 Variations in the specific leaf dry weight (SLWd) (A) and specific leaf fresh weight (SLWf) (B) in the flag leaves of four wheat varieties during the heading stage (mean ± SD, n = 15). Different lower-case letters indicate significant differences among wheat varieties (p = 0.05).

Fig. 3 Variations in the maximum photochemical efficiency of PSII (Fv/Fm and 1/Fo - 1/Fm) in the flag leaves of four wheat varieties after 20 min dark adaptation at three measurement times on a clear day during the heading stage (mean ± SD, n = 12). Different lower-case letters indicate significant differences among three typical times within wheat varieties on a clear day (p = 0.05).

Fig. 4 Variations in the minimal fluorescence of PSII reaction centers (Fo) in the flag leaves of four wheat varieties after 20 min dark adaptation at three typical times during the heading stage (mean ± SD, n = 12). Different lower-case letters in each column indicate significant differences among three typical times within wheat varieties on a clear day (p = 0.05).

Fig. 5 Analysis of the PSII maximal photochemical efficiency (Fv′/Fm′) (A) and actual photochemical efficiency (ΦPSII) (B) in the flag leaves of four wheat varieties between morning and afternoon at a given light intensity during the heading stage (mean ± SD, n = 6). Different capital and lower-case letters in figures indicate significant differences in Fv′/Fm′ and ΦPSII, respectively, between morning and afternoon (p = 0.05). ns, no significant differences between morning and afternoon (p > 0.05); * and **, significant and highly significant differences between morning and afternoon (p < 0.05 and p < 0.01).

Fig. 6 Analysis of PSII photochemical quenching coefficient (qP) (A) and non-photochemical quenching coefficient (NPQ) (B) in the flag leaves of four wheat varieties between morning and afternoon at a given light intensity during the heading stage (means ± SD, n = 6). Different capital and lower-case letters in figures indicate significant differences in qP and NPQ, respectively, between morning and afternoon (p = 0.05). ns, no significant differences between morning and afternoon; * and **, significant and highly significant differences between morning and afternoon (p < 0.05 and p < 0.01).

Fig. 7 Variations in the fraction of PSII reaction centers that are open (qL) (A), PSII regulatory energy dissipation in quantum yield (ΦNPQ) (B), and non-regulatory energy dissipation in quantum yield (ΦNO) (C) in the flag leaves of four wheat varieties between morning and afternoon at the given light intensity during the heading stage (means ± SD, n = 6). Different capital and lower-case letters in figures indicate significant differences in qL, ΦNPQ and ΦNO, respectively, between morning and afternoon (p = 0.05). ns, no significant differences between morning and afternoon; * and **, significant and highly significant differences between morning and afternoon (p < 0.05 and p < 0.01).

References 31

[1]	Baker NR (2008). Chlorophyll fluorescence: a probe of photosynthesis in vivo. Annual Review of Plant Biology, 59, 89-113. DOI URL
[2]	Baker NR, Rosenqvist E (2004). Applications of chlorophyll fluorescence and improve crop production strategies: an examination of future possibilities. Journal of Experimental Botany, 55, 1607-1621. DOI URL PMID
[3]	Bilger W, Björkman O (1990). Role of the xanthophyll cycle in photoprotection elucidated by measurements of light-induced absorbance changes, fluorescence and photosynthesis in leaves of Hedera canariensis. Photosynthesis Research, 25, 173-185.
[4]	Butler WL (1978). Energy distribution in the photochemical apparatus of photosynthetic. Annual Review of Plant Physiology, 29, 345-378.
[5]	Editor Committee of Historical Recorders of Dulan County (2001). Historical Recorders of Dulan County. Shaanxi People’s Press, Xi’an. 201-209. (in Chinese)
	[ 都兰县县志编委会 (2001). 都兰县志. 陕西人民出版社, 西安. 201-209.]
[6]	Galvez-Valdivieso G, Fryer MJ, Lawson T, Slattery K, Truman W, Smimoff N, Asami T, Davies WJ, Jones AM, Baker NR, Mullineaux PM (2009). The high light response in Arabidopsis involves ABA signaling between vascular and bundle sheath cells. The Plant Cell, 21, 2143-2162. URL PMID
[7]	Genty B, Briantais JM, Baker NR (1989). The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochimica et Biophysica Acta, 990, 87-92.
[8]	Govindjee (2002). A role for a light-harvesting antenna complex of photosystem II in photoprotection. The Plant Cell, 14, 1663-1668. DOI URL PMID
[9]	Havaux M, Greppin H, Strasser RJ (1991). Functioning of photosystems I and II in pea leaves exposed to heat stress in the presence or absence of light. Planta, 186, 88-98. URL PMID
[10]	Hendrikson L, Furbank RT, Cow WS (2004). A simple alternative approach to assessing the fate of absorbed light energy using chlorophyll fluorescence. Photosynthesis Review, 82, 73-81.
[11]	Kramer DM, Johnson G, Kiirats O, Edwards GE (2004). New fluorescence parameters for the determination of Q_A redox state and excitation energy fluxes. Photosynthesis Research, 79, 209-218. URL PMID
[12]	Larcher W (1980). Physiological Plant Ecology. 2nd edn. Springer-Verlag, New York. 5-60.
[13]	Lima Neto MC, Lobo AKM, Martins MO, Fontenele AV, Silveira JAG (2014). Dissipation of excess photosynthetic energy contributes to salinity tolerance: a comparative study of salt-tolerant Ricinus communis and salt-sensitive Jatropha curcas. Journal of Plant Physiology, 171, 23-30. DOI URL PMID
[14]	Maxwell K, Johnson GN (2000). Chlorophyll fluorescence―a practical guide. Journal of Experimental Botany, 51, 659-668. DOI URL PMID
[15]	Middleton EM, Teramura AH (1993). The role of flavonol glycoside and carotenoids in protecting soybean from ultraviolet-B damage. Plant Physiology, 103, 475-480.
[16]	Murchie EH, Niyogi KK (2011). Manipulation of photoprotec- tion to improve plant photosynthesis. Plant Physiology, 155, 86-92. DOI URL PMID
[17]	Niyogi KK, Truong TB (2013). Evolution of flexible non- photochemical quenching mechanisms that regulate light harvesting in oxygenic photosynthesis. Current Opinion in Plant Biology, 16, 307-314. DOI URL PMID
[18]	Oxborough K, Baker NR (1997). Resolving chlorophyll a fluor- escence images of photosynthetic efficiency into photo- chemical and non-photochemical components: calculation of q_P and F_v′/F_m′ without measuring F_o′. Photosynthesis Research, 54, 135-142.
[19]	Quick WP, Stitt M (1989). An examination of factors con- tributing to non-photochemical quenching of chlorophyll fluorescence in barley leaves. Biochimica et Biophysica Acta, 977, 287-296.
[20]	Sáez PL, Bravo LA, Latsague MI, Toneatti MJ, Sánchez-Olate M, Ríos DG (2013). Light energy management in micropropagated plants of Castanea sativa, effects of photoinhibition. Plant Science, 201, 12-24. DOI URL PMID
[21]	Shi SB, Shang YX, Zhu PJ, Yang L, Zhang B (2011). Effects of solar UV-B radiation on the efficiency of PSII photochemistry in the alpine plant Saussurea superba under different weather conditions in the Qinghai-Tibet Plateau of China. Chinese Journal of Plant Ecology, 35, 741-750. (in Chinese with English abstract) DOI URL
	[ 师生波, 尚艳霞, 朱鹏锦, 杨莉, 张波 (2011). 不同天气类型下UV-B辐射对高山植物美丽风毛菊叶片PSII光化学效率的影响分析. 植物生态学报, 35, 741-750.]
[22]	Shi SB, Zhu WY, Li HM, Zhou DW, Han F, Zhao XQ, Tang YH (2004). Photosynthesis of Saussurea superba and Gentiana straminea is not reduced after long-term enhancement of UV-B radiation. Environmental and Experimental Botany, 51, 75-83.
[23]	Su TZ, Pan JS (1981). An analysis of the physiological feature of the higher yielding ability of spring wheat in the Xiangride farm, Qinghai Province. Acta Agronomica Sinica, 7, 19-25. (in Chinese with English abstract)
	[ 苏悌之, 潘锦珊 (1981). 青海香日德春小麦高产的生理特性分析. 作物学报, 7, 19-25.]
[24]	Sun HL (2007). Progress of ecological techniques being the source of sustainable high yield of crop—the inspiration from the high yield fields of wheat in Xiangride area of Qinghai Province after revisiting. Chinese Journal of Eco-Agriculture, 15, 181-183. (in Chinese with English abstract)
	[ 孙鸿良 (2007). 生态技术进步造就了作物高产不衰的典型—重访青海香日德地区春小麦高产田的启示. 中国生态农业学报, 15, 181-183.]
[25]	Takahashi S, Milward SE, Yamori W, Evans JR, Hillier W, Badger MR (2010). The solar action spectrum of photosystem II damage. Plant Physiology, 153, 988-993. DOI URL PMID
[26]	Tikkanen M, Mekala NR, Aro EM (2013). Photosystem II photoinhibition-repair cycle protects photosystem I from irreversible damage. Biochimica et Biophysica Acta, 1837, 210-215. URL PMID
[27]	Xu DQ (2002). Photosynthetic Efficiency. Shanghai Scientific and Technical Press, Shanghai. (in Chinese)
	[ 许大全 (2002). 光合作用效率. 上海科学技术出版社, 上海.]
[28]	Yamori W, Hikosaka K, Way DA (2014). Temperature response of photosynthesis in C₃, C₄, and CAM plants: temperature acclimation and temperature adaptation. Photosynthesis Research, 119, 101-117. URL PMID
[29]	Yu BH, Lü CH (2011). Assessment of ecological vulnerability on the Tibetan Plateau. Geographical Research, 30, 2289-2294. (in Chinese with English abstract)
	[ 于伯华, 吕昌河 (2011). 青藏高原高寒区生态脆弱性评价. 地理研究, 30, 2289-2294.]
[30]	Zhang SR (1999). A discussion on chlorophyll fluorescence kinetics parameters and their significance. Chinese Bulletin of Botany, 16, 444-448. (in Chinese with English abstract)
	[ 张守仁 (1999). 叶绿素荧光动力学参数的意义及讨论. 植物学通报, 16, 444-448.]
[31]	Zhu GL, Zhong HW, Zhang AQ (1990). Plant Physiological Experiment. Beijing University Press, Beijing. 51-54. (in Chinese)
	[ 朱广廉, 钟诲文, 张爱琴 (1990). 植物生理学实验. 北京大学出版社, 北京. 51-54.]