Helicotylenchus dihystera

Zeng, Yongsan, Ye, Weimin, Tredway, Lane, Martin, Samuel & Martin, Matt, 2012, Taxonomy and morphology of plant-parasitic nematodes associated with turfgrasses in North and South Carolina, USA, Zootaxa 3452, pp. 1-46 : 9

Helicotylenchus dihystera

( Fig. 2 I, J)

Measurements. See Table 3 .

Remarks. Helicotylenchus dihystera was described from soil around sugarcane roots ( Saccharum officinarum ) in Harwood, Australia. It is a cosmopolitan species with a wide geographical distribution, occurring in 17 countries in Europe, 28 in Asia, 30 in Africa, three in North America, 18 in Central America and Caribbean, eight in South America, and eight in Oceania (CABI 2010). In the USA, it occurs in Alabama, Arkansas, California, Colorado, Florida, Georgia, Hawaii, Louisiana, Maryland, Mississippi, Missouri, NC, South Dakota and Texas (CABI 2010). This species has a wide host range including sugarcane, potato, banana, rice, tea, avocado, coffee, maize, beans, wheat, rye, oat, sorghum, and turfgrass ( Kinloch 1971; Siddiqi 1972; Lucas et al. 1974). There was a significant correlation between numbers of H. dihystera and reduced growth of Kentucky bluegrass in a landscape setting in Lincoln, Nebraska ( Sumner 1967) and of turf in bowling greens in Adelaide, Australia ( Wallace 1971). In this study, H. dihystera was found in 34 counties in both NC and SC. It had high prevalence in all three management zones (green, fairway and tee) and two grass species (bentgrass and zoysiagrass). Both morphology and morphometrics fit the description of other populations ( Sher 1966; Siddiqi 1972).

Figures

FIGURE 2. Micrographs of Hoplolaimus galeatus, Scutellonema brachyurum and Helicotylenchus dihystera from turfgrasses in NC and SC. All scale bars = 20 μm. A. Pharyngeal region of H. galeatus. B. Vulval region of H. galeatus. C. Female tail of H. galeatus. D, E. Male tails of H. galeatus. F. Pharyngeal region of S. brachyurum. G. Vulval region of S. brachyurum. H. Female tail of S. brachyurum. I. Pharyngeal region of H. dihystera. J. Vulva and tail region of H. dihystera.