Optimizing methods to sample and quantify stem and bulb nematode, Ditylenchus dipsaci, in garlic, Allium sativum, field soil

Figures & data

Table 1. Populations of plant-parasitic nematode genera in the top 5 cm and bottom 5–20 cm of the soil profile determined using the sugar centrifugal flotation and Baermann pan extraction method

		Nematodes per kilogram of soil^a
Soil Depth	Extraction Method^b	Stem and bulb	Spiral	Root lesion	Root-knot	Ring	Total root nematodes^c
0–5 cm	SCF	556 a^d	359 ab	224 ns^e	115 ns	66 ns	522 ab
	BP	14 b	127 b	212	35	0	311 b
5–20 cm	SCF	77 b	673 a	363	440	86	957 a
	BP	6 b	274 ab	513	90	0	706 ab

^a Number of fields with each nematode genus: Stem and bulb (n = 14); Spiral (n = 14); Root lesion (n = 17); Root-knot (n = 4); Ring (n = 7); Total root nematodes (n = 19)

^b Nematode extraction method: sugar centrifugal flotation (SCF) and Baermann pan (BP) method

^c Total root nematodes do not include stem and bulb nematode

^d Numbers in a column followed by the same letter are not significantly different at P = 0.05, Tukey’s test

^e ns indicates that no significant differences were found among the treatments.

Fig. 1 Mean percentages of stem and bulb nematode recovered from two sugar centrifugal flotation (SCF-1 and SCF-2) and four Baermann pan (BP) extraction methods in the first (1) and second (2) trial. Different letters above each bar indicate a significant difference at P < 0.05, Tukey’s test