1. Online Resource 2 Article title: The interrelationship between the lower oxygen limit, chlorophyll fluorescence and the xanthophyll cycle in plants Journal name: Photosynthesis Research Author names: A. Harrison Wright 1,2 *, John M. DeLong 1, Arunika H.L.A.N. Gunawardena 2, and Robert K. Prange 1 1 Atlantic Food and Horticulture Research Centre, Agriculture and Agri-Food Canada, Kentville, NS, B4N 1J5, Canada. 2 Department of Biology, Dalhousie University, Halifax, NS, B3H 4J1, Canada Corresponding author email (*): harrison.wright@agr.gc.ca

2. Online Resource 2 – ethanol fermentation abbreviations: ADP, adenosine diphosphate; ATP, adenosine triphosphate; Cyt b 6 /f, cytochrome b 6 /f complex; Fd, ferrodoxin; FNR, ferredoxin-NADP + reductase; NADH, nicotinamide adenine dinucleotide ; NADPH, nicotinamide adenine dinucleotide phosphate; Ndh, NADPH-dehydrognase; OAA, oxaloacetate; PC, plastocyanin; P i, phosphate; PQ, plastoquinonol; PTOX, chloroplast terminal oxidase; Q A, plastoquinone Q A ; ROS, reactive oxygen species

3. Online Resource 2 – mitochondria / chloroplast interactions abbreviations: ADP, adenosine diphosphate; ATP, adenosine triphosphate; Cyt b 6 /f, cytochrome b 6 /f complex; Fd, ferrodoxin; FNR, ferredoxin-NADP + reductase; NADH, nicotinamide adenine dinucleotide ; NADPH, nicotinamide adenine dinucleotide phosphate; Ndh, NADPH-dehydrognase; OAA, oxaloacetate; PC, plastocyanin; P i, phosphate; PQ, plastoquinonol; PTOX, chloroplast terminal oxidase; Q A, plastoquinone Q A ; ROS, reactive oxygen species

4. Online Resource 2 – chlororespiration Reductant Sources abbreviations: ADP, adenosine diphosphate; ATP, adenosine triphosphate; Cyt b 6 /f, cytochrome b 6 /f complex; Fd, ferrodoxin; FNR, ferredoxin-NADP + reductase; NADH, nicotinamide adenine dinucleotide ; NADPH, nicotinamide adenine dinucleotide phosphate; Ndh, NADPH-dehydrognase; OAA, oxaloacetate; PC, plastocyanin; P i, phosphate; PQ, plastoquinonol; PTOX, chloroplast terminal oxidase; Q A, plastoquinone Q A ; ROS, reactive oxygen species

5. Online Resource 2 – chlorofermentation? Reductant Sources abbreviations: ADP, adenosine diphosphate; ATP, adenosine triphosphate; Cyt b 6 /f, cytochrome b 6 /f complex; Fd, ferrodoxin; FNR, ferredoxin-NADP + reductase; NADH, nicotinamide adenine dinucleotide ; NADPH, nicotinamide adenine dinucleotide phosphate; Ndh, NADPH-dehydrognase; OAA, oxaloacetate; PC, plastocyanin; P i, phosphate; PQ, plastoquinonol; PTOX, chloroplast terminal oxidase; Q A, plastoquinone Q A ; ROS, reactive oxygen species