. 2021 Feb 11;134(6):1663–1675. doi: 10.1007/s00122-020-03761-3

Table 1.

Intraspecific variation of carbon isotope discrimination/composition in C₄ plants

Species	Genetic material	Carbon isotopic composition (δ¹³C) in ‰	Carbon isotope discrimination (∆¹³C) in ‰	Maximum genotypic difference (‰)	Tissue	References
Zea mays	50 commercial inbred lines	− 11.6 to − 10.7		0.9	Grain	Tieszen and Fagre (1993)
	59 diverse accessions	− 12.00 to − 9.86		2.14	Grain
	193 diverse accessions	− 11.5 to − 9.7		1.8	Grain
	6 lines with contrasting drought tolerance, 35 hybrids, 2 drought tolerant and 2 drought sensitive inbred lines		4.88 to 5.41	0.53	Leaf	Monneveux et al. (2007)
			4.10 to 4.54	0.44	Ears	Monneveux et al. (2007)
	16 hybrids, one commercial hybrid as a check		4.98 to 5.53	0.55	Leaf	Cabrera-Bosquet et al. (2009)
	16 hybrids, one commercial hybrid as a check		3.59 to 4.01	0.42	Grain	Cabrera-Bosquet et al. (2009)
	Mean of 15 tropical inbred lines and mean of 16 of their hybrids		5.30 to 5.64	0.34	Leaf	Araus et al. (2010)
			3.82 to 4.01	0.19	Grain	Araus et al. (2010)
	2 varieties	− 14.78 to − 13.13		1.65	Leaf	Pengelly et al. (2011)
	2 varieties	− 15.08 to − 15.02		0.06	Husk	Pengelly et al. (2011)
	89 introgression lines, derived from a dent and a flint inbred line		4.24 to 5.84	1.6	Grain (field)	Gresset et al. (2014)
			4.98 to 6.55	1.57	Grain (GH)	Gresset et al. (2014)
			5.42 to 6.98	1.56	Leaf (GH)	Gresset (2014)
	29 inbred lines (including 26 NAM^a founders)	− 15.0 to − 13.7		1.3	Leaf	Kolbe et al. (2018)
	31 inbred lines (including 26 NAM founders)	− 13.02 to − 11.61 (2015)		1.41	Leaf	Twohey et al. (2019)
	31 inbred lines (including 26 NAM founders)	− 13.29 to − 12.22 (2016)		1.07	Leaf	Twohey et al. (2019)
Panicum coloratum	4 varieties	− 12.74 to − 11.36		1.38	Leaf	Ohsugi et al. (1988)
Saccharum spp. Hybrid	2 cultivars		4.4 to 4.7	0.3	Leaf	Meinzer et al. (1994)
Saccharum spp. Hybrid	4 cultivars		3.2 to 3.9	0.7	Leaf	Saliendra et al. (1996)
Sorghum bicolor Moench	12 genotypes		4.24 to 4.84	0.6	Leaf	Hubick et al. (1990)
	45 cultivars		3.10 to 4.15	1.05	Leaf	Hammer et al. (1997)
	30 lines		2.46 to 2.89	0.43	Leaf (GH)	Henderson et al. (1998)
	4 lines		3.43 to 4.10	0.67	Leaf (field)	Henderson et al. (1998)

^aNAM, nested association mapping, the NAM founder lines include the 26 most extensively researched maize lines, which represent a broad cross section of modern maize diversity (Yu et al. 2008)

GH, greenhouse