Table 4

Reproduction of six populations of M. xenoplax on resistant and susceptible grape cultivars in glasshouse trials.

	Cultivars
	Nematodes (g⁻¹ soil)^a,b				Comparative resistance^c
Population^d	420A Mgt	101-14 Mgt	3309C	Pinot noir	420A Mgt	101-14 Mgt	3309C
^aPots were infested with nematodes of mixed stages at 100/pot or 0.025 nematodes g⁻¹ soil that were handpicked from field or pot culture soil. Population densities evaluated after 20 wk.
^bBased on nematodes extracted from a 250 cm³ subsamples of soil and from the root systems. Pots contained 4000 g soil.
^cReproduction of M. xenoplax populations on a rootstock cultivar in relation to Pinot noir, i.e., nematode Rf on a rootstock/Rf on Pinot noir soil.
^dOR-SWV (southern Willamette Valley, OR), OR-NWV-E and OR-NWV-D (North Willamette Valley), OR-RV (Rogue Valley), WA-YV (Yakima Valley, WA), CA-CV (Fresno, CA).
^eMeans for each population in each column followed by different letters are significantly different according to Fisher’s LSD.
OR-SWV	0.001 a^e	0.019 a	0.631 a	2.439 a	0.001	0.008	0.259
OR-NWV-E	0.011 a	0.047 a	3.814 ab	13.893 b	0.001	0.003	0.292
OR-NWV-D	0.007 a	0.038 a	0.878 b	2.489 c	0.003	0.052	0.363
OR-RV	0.025 a	0.050 a	7.020 b	11.313 b	0.002	0.004	0.605
WA-YV	0.009 a	0.133 a	1.086 a	4.050 b	0.002	0.032	0.257
CA-CV	0.620 a	2.445 a	8.089 ab	14.787 b	0.042	0.135	0.547