High-throughput three-dimensional visualization of root system architecture of rice using X-ray computed tomography

Table 2 Literature reports on use of X-ray CT for rice root visualization over the last decade

Detectable root		Pot size		Other parameters							Soil type	References
Target	Diameter [mm]	Diameter [mm]	Height [mm]	Voltage [kV]	Current [kV]	Resolution [μm]	Distance [mm]^b	Scan time [min]	Filter	Dose [Gy]	Soil type	References
Main root	> 0.3	200 (180)^a	250	225	500	300	900	10	1.0 mm Cu	< 0.09	Calcined clay^e	This study
Main root	> 0.2	160 (140)^a	250	225	500	200	407	10	1.0 mm Cu	< 0.44	Calcined clay^e	This study
Main root	NA	100 (80)^a	210 (56)^a	120	185	40	NA	282	1.0 mm Cu	NA	Paddy soil, sieved	[39]
Main root	> 0.2	48	80	110	110	30	NA	NA	0.1 mm Cu	NA	Paddy soil, sieved	[40]
Main root	NA	80	180	180	180	60	NA	150	0.1 mm Cu	NA	Sandy clay loam soil, sieved	[41]
Main root	NA	55	100	130	240	27.3	227	73	0.1 mm Cu	1.5	Sandy loam soil, sieved	[42]
Main root	NA	72	150	180	180	50	2045^c	7.2	NA	NA	Clay loam, sieved	[43]
Main root	> 0.4	66	108	NA	NA	200	521	75^d	NA	NA	Play sand, sieved, or a mixture of peat-based substrate^f and calcined clay^g	[44]
Main root	> 0.2	55	150	110–130	320	57.3	225	73	0.2 mm Cu	1.41	Loamy sand soil and clay loam soil, sieved	[45]

^aScanning area was reduced to the diameter indicated in the parentheses by cropping the images
^bSource–rotation axis distance
^cThere was a contradiction here, in that the source–rotation axis distance was longer than the source–detector distance
^dThe value was calculated by multiplying the exposure time and the projection
^eProfile^® Greens Grade™, PROFILE Products, USA
^fFafard #52 soil mix, Conrad Fafard Inc, USA
^gTurface^®, PROFILE Products, USA

ISSN: 1746-4811