Table I. Minimum, maximum, and median LRBD in different populations phenotyped by various researchers at several locations in the world.

Locations are as follows: D, Juelich, Germany; PA, State College, PA; and SA, Alma, South Africa. Some of the experiments included nutrient treatments: LN, low nitrogen availability; and LP, low phosphorus availability. Data were collected by counting the number of roots along a nodal root segment. Data were supplied by the person indicated under source: H.S., H. Schneider; L.Y., L. York; A.Z., A. Zhan; and J.P., J.A. Postma. WiDiv, Wisconsin Diversity panel; IBM, intermated B73 × Mo17; NAM, nested association mapping.

Population	No. of Genotypesa	Experiment	Location	Date	Nutrient Treatments	Source	LRBD
							Minimum	Maximum	Median
							cm−1
WiDiv	527	Field	SA	2010	–	H.S.	1	15	9
	400	Field	SA	2011, 2012	–	H.S.	0	18	6
	400	Field	SA	2013	LN	H.S.	0	13	6
IBM	30	Field	SA, PA	2012, 2013, 2014	LN	L.Y.	0	41	6
	18	Mesocosms	PA	2013	LN	A.Z.	1	10	4
NAM	1,235	Field	SA	2010, 2011, 2012	–	H.S.	0	14	6
	6	Rhizotrons	D	2011	LN, LP	J.P.	1	14	4

^aMeans for the individual treatments are presented in Supplemental Appendix S4, Figure S5.