Distribution and Prevalence of Plant-Parasitic Nematodes of Turfgrass at Golf Courses in China

Simple Summary Plant-parasitic nematodes (PPNs) are one of the most important pests to cause infectious diseases on turfgrass. Numerous studies have been conducted on PPNs associated with turfgrass worldwide. However, little published research is available on PPNs associated with turfgrass in China. Information on the occurrence, distribution, diversity, and dominant species of PPNs associated with turfgrass in different regions of China is limited, making it challenging to design suitable management practices for control. In this study, we assessed morphological characteristics and utilized molecular methods to identify PPNs from turfgrass soil samples. The purpose of this study was to determine the species, distribution, incidence, and diversity of PPNs associated with turfgrass at golf courses in North, East, and South China (NC, EC, and SC, respectively). The results provide valuable information for the management of PPNs on turfgrass in China. We sampled 127 turfgrass soil samples from 33 golf courses in NC, EC, and SC for plant-parasitic nematodes (PPNs). PPNs were extracted from soil samples using the shallow dish method and were identified at the genus or species levels with a combination of morphological and molecular methods. The results revealed 41 species of nematode belonging to 20 genera and 10 families. Nine genera are new records of PPNs associated with turfgrass in China. The PPNs show strong geographical distributions. Of the 20 genera, Helicotylenchus, Paratrichodorus, Hoplolaimus, Meloidogyne, Hemicriconemoides, and Mesocriconema showed higher infestation and frequency, and most of these genera had numbers in soil samples above established damage thresholds. Four golf courses had soil samples with PPNs > 30%, indicating the potential for nematode damage. The biodiversity indices H', SR, J', lambda, and H-2 showed significant differences among different regions and turfgrass species; H', SR, J', and H-2 were significantly higher in EC than in NC and SC, while lambda was lowest in EC. Creeping bentgrass had the highest H', SR, J', and H-2 and the lowest lambda in comparison with seashore paspalum and hybrid bermudagrass. These findings provide baseline information on the occurrence of turfgrass-associated PPNs in China, and have important implications for the effective management of PPNs causing damage on turfgrass.