. 2017 Jun 9;174(4):2289–2301. doi: 10.1104/pp.17.00357

Table II. Summary statistics from an analysis of covariance model of root length as influenced by root tip geometry or root diameter, soil bulk density (1.3, 1.45, or 1.6 g cm⁻³), and their interaction, based on mean values (n = 6) of genotype-bulk density combinations.

Assumed Root Tip Shape	Effect	Root Elongation Rate
		mm d⁻¹
Cone	Bulk density	121.1**
	iSF_cone	5.2*
	Bulk density:iSF_cone	0.5 n.s.
	R²	0.87
Spheroid	Bulk density	121.1**
	iSF_spheroid	5.2*
	Bulk density:iSF_spheroid	0.5 n.s.
	R²	0.87
	Bulk density	107.3**
	dm_root	0.1 n.s.
	Bulk density:dm_root	18.8 n.s.
	R²	0.86

Numbers indicate F values. Asterisks denote significant effects at P < 0.05 (*) and P < 0.01 (**); n.s. denotes nonsignificant effects. iSF, Inverse of cone (r_{root tip}/l_{root tip}) and spheroid shape factor (2r_{root tip}/πl_{root tip}); r_{root tip}, radius at the base of a root tip; l_{root tip}, length of a root tip; dm_root, root diameter.

Table II. Summary statistics from an analysis of covariance model of root length as influenced by root tip geometry or root diameter, soil bulk density (1.3, 1.45, or 1.6 g cm−3), and their interaction, based on mean values (n = 6) of genotype-bulk density combinations.

Table II. Summary statistics from an analysis of covariance model of root length as influenced by root tip geometry or root diameter, soil bulk density (1.3, 1.45, or 1.6 g cm⁻³), and their interaction, based on mean values (n = 6) of genotype-bulk density combinations.