Eleven golf courses and eight football pitches, located in Belgium, were surveyed for plant-parasitic nematodes. This revealed a remarkably high diversity: 52 different species/taxa were identified morphologically, belonging to 23 genera and nine families. Among the most prevalent nematodes on both sports field types were Helicotylenchus pseudorobustus and Meloidogyne naasi (> 85% and > 45% of the analysed samples, respectively). Golf greens contained a higher density and diversity of cyst nematodes than football fields. Cyst nematode species included Punctodera punctata, Heterodera mani, H. ustinovi, H. bifenestra and H. hordecalis. Multivariate statistics of the first three species showed that they could be separated based on morphometrical characters of juveniles, but not on values based on the vulva! pattern. Several detected species, e.g., Meloidogyne minor, are a potential source of infestation of agricultural fields. This study shows the importance of plant-parasitic nematodes in turf grass in temperate Europe. In addition, a comparison between two extraction methods revealed that significantly more nematodes were extracted with the zonal centrifuge than after 2 weeks extraction with the Baermann method, except for juveniles of Meloidogyne spp. and cyst-forming specie

Beet cyst nematodes, Heterodera schachtii and H. betae, cause damage to sugar beet production and could become even more important with an increase in soil temperatures. In northern Germany, temperatures are expected to rise by 4°C by 2100. In this study we investigated the hatch of two beet cyst nematode species at constant temperatures as well as simulated temperature conditions set to be 4°C higher than the standard temperature regime. The effect of different constant temperatures on the emergence of second-stage juveniles of H. schachtii and H. betae was investigated using six incubators set at 5, 10, 15, 20, 25 and 30°C for a period of 6 weeks. In a second experiment, the effect of increased and standard temperature regimes on the emergence of second-stage juveniles of H. schachtii and H. betae was investigated in climate chambers for 12 weeks. The highest cumulative hatching rates for H. schachtii were observed at temperatures between 15 and 30°C and for H. betae between 20 and 30°C, suggesting that this can be considered as the optimal temperature range for hatch. The emergence of juveniles of both beet cyst nematode species started at 5°C, but cumulative hatch percentages were less than 1%. Differences in final cumulative hatching rate of H. schachtii and H. betae between the increased and standard temperature regime were not significant.

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The commercial use of the entomopathogenic nematodeHeterorhabditis bacteriophoraas a biocontrol agent against noxious insects is limited due to its relatively short shelf-life. Longevity of dauer juveniles (DJ) during storage and in transit to end users is considerably restricted by environmental stresses. As a derivative stress triggered by environmental factors, oxidative stress causes a strong internal metabolic imbalance leading to lifespan reduction. In this study, the relation between DJ oxidative stress tolerance and longevity inH. bacteriophorawas investigated at 25 and 7°C. A strong and significant correlation between DJ oxidative stress tolerance and longevity during storage in Ringer’s solution ( at 7°C; at 25°C) was recorded. Phenotyping of these traits was performed for 40H. bacteriophorawild type strain and inbred line collections. At 25°C, the mean time survived in Ringer’s by 50% of the DJ (MTS50) ranged from 21 to 57 days, whereas under oxidative stress, survival was from 3 to 22 days. At 7°C, a maximum MTS50of 94 days was assessed when DJ were stored in Ringer’s, while the maximum MTS50was only 25 days with oxidative stress induction. The heritability of DJ tolerance to oxidative stress, determined by using homozygous inbred lines, is high (), an indication of a high probability for successful selective breeding. In a subset of preselectedH. bacteriophorainbred lines, DJ oxidative stress tolerance correlated with the DJ survival (persistence) after application to sand (). The study provides fundamental data required for a genetic breeding programme to produce hybrids with improved stress tolerance and prolonged shelf-life and soil persistence.