Identification of plant-parasitic nematodes present in roots and rhizophere of rice (Oryza sativa) in Soc Trang province

Rice (Oryza sativa) is a crucial staple crop in Vietnam, and plant-parasitic nematodes are of increasing concern due to their negative impacts. This study aimed to identify the nematode species parasitizing rice (Dai Thom 8) in several cultivation areas of Soc Trang province. The results showed that four genera including Meloidogyne, Hirschmanniella, Tylenchorhynchus, and Tylenchus were detected. Based on morphological characteristics and morphometrics, seven nematode species were identified: Meloidogyne graminicola, Hirschmanniella diversa, H. mucronata, H. oryzae, Tylenchorhynchus leviterminalis, T. nudus, and Tylenchus sp. Notably, Hirschmanniella appeared with high density and was present in 100% of surveyed samples, with higher parasitic density in root samples than in soil samples. Meloidogyne graminicola was common but occurred at low density in the flooded rice model, while Tylenchorhynchus appeared sporadically, with higher density in roots than in soil. This study indicates that the rice cultivation area in Soc Trang province has low nematode diversity, with Hirschmanniella identified as the main harmful nematode in the rhizosphere. These results provide an important scientific basis for developing control measures in future research.