Table 2.

Recovery of root segments buried in different substrates measured with MRI

Substrate	NMR soil	Sp2.1	Sp2.2	Sp2.3	Sp2.4	Sp5M	Sp6S	Brown’s soil
Seminal roots unprocessed soil	4	4	4	4	3	4	2	4
Seminal roots demag. soil	N/A	4	4	4	4	4	1	N/A
Lateral roots unprocessed soil	3	4	4	3	0	0	0	4
Lateral roots demag. soil	N/A	4	4	4	0	0	0	N/A

From an excavated root system lateral roots (diameter 250–350 µm) and seminal roots (diameter 750–1000 µm) were selected. For each class, four 1 cm long root segments were buried in soil and measured with MRI. Listed are the numbers of visually detectable root segments in unprocessed and demagnetized substrates