Detection of Pythium spp. in Golf Course Irrigation Systems

Host Range and Loop-Mediated Isothermal Amplification Detection of Globisporangium sylvaticum from Guizhou, China

Globisporangium, especially G. sylvaticum, causes devastating root rot, blight, and other diseases in various species of cash crops. To investigate the distribution and host range of G. sylvaticum in Guizhou, a suitable habitat for this pathogen, we collected 156 root-diseased samples, isolated the pathogens, and found that G. sylvaticum is widespread and has eleven host plants, including four novel hosts. Furthermore, to effectively identify G. sylvaticum, we developed a simple and dependable method based on loop-mediated isothermal amplification (LAMP), which used a primer set designed from the internal transcribed spacer sequences with high specificity and sensitivity of 1 pg/μL. Additionally, to perform field identification, we used the "Plant-LAMP" method with crude DNA extraction to detect the pathogen in 45 root samples from nine species of plants. Our results showed that this method could effectively detect G. sylvaticum in diseased roots. Therefore, our findings not only enrich existing research on the diversity of pathogenic Globisporangium in Guizhou but also present an efficient LAMP field detection method that could significantly contribute to plant disease management and prevention.

Global Distribution and Clinical Features of Pythiosis in Humans and Animals

Pythiosis is a difficult-to-treat infectious disease caused by Pythium insidiosum. The condition is unfamiliar among healthcare workers. Manifestation of pythiosis is similar to other fungal infections, leading to misdiagnosis and delayed treatment. The geographical extent of pythiosis at a global scale is unclear. This study aimed to analyze the clinical information recorded in the scientific literature to comprehensively project epidemiological characteristics, clinical features, and future trends of pythiosis. From 1980 to 2021, 4203 cases of pythiosis in humans (n = 771; 18.3%) and animals (primarily horse, dog, and cow; n = 3432; 81.7%), with an average of 103 cases/year, were recruited. Pythiosis case reports significantly increased in the last decade. Pythiosis spanned 23 tropical, subtropical, and temperate countries worldwide. Some patients acquired pythiosis from a trip to an endemic country. Strikingly, 94.3% of human cases were in India and Thailand, while 79.2% of affected animals were in the U.S.A. and Brazil. Clinical features of pythiosis varied. Vascular and ocular pythiosis were only observed in humans, whereas cutaneous/subcutaneous and gastrointestinal infections were predominant in animals. Mortality depended on host species and clinical forms: for example, none in patients with ocular pythiosis, 0.7% in cows with a cutaneous lesion, 26.8% in humans with vascular disease, 86.4% in dogs with gastrointestinal pathology, and 100% in several animals with disseminated infection. In summary, this study reports up-to-date epidemiological and clinical features of pythiosis in humans and animals. It increases awareness of this life-threatening disease, as the illness or outbreak can exist in any country, not limited to the endemic areas.