Genetic Structure and Asymmetric Migration of Wheat Stripe Rust Pathogen in Western Epidemic Areas of China

Puccinia striiformis f. sp. tritici causes severe global epidemics of wheat stripe rust primarily by airborne urediniospores. Understanding long-distance migration patterns of P. striiformis f. sp. tritici is critical for disease forecasting and management. Although the western epidemic areas in China have been considered as the source of inoculum spread eastward across the country, migration pathways among different populations within the western epidemic areas are poorly understood. In this study, we investigated the population genetics of 200 P. striiformis f. sp. tritici isolates from western epidemic areas using amplified fragment length polymorphism and simple sequence repeat markers. A coalescent approach was also used to calculate the migration rates among populations. Data analyses with both marker systems indicated high genetic diversity in each regional population. The Mantel test revealed significant positive correlation between genetic and geographic distances. Both discriminant analysis of principal components and STRUCTURE analysis supported moderate population structure shaped by seasonality and geography. The calculated migration rates indicated the presence of asymmetric migration between major populations in western epidemic areas, with greater migration rates from high elevation, oversummering areas to low elevation, overwintering areas. Sichuan Basin, one of the low elevation, overwintering areas, sampled in both fall and spring, was inferred as a recipient in fall but a donor in spring. Migration among P. striiformis f. sp. tritici populations may be partly attributable to terrace farming and prevailing wind direction in different seasons. Our study provides a better understanding of fine-scale population structure and the interregional migration pattern of P. striiformis f. sp. tritici in northwestern China and will inform future rust management.

Changes in interregional migration of patients hospitalized in Poland - 2013-2017

OBJECTIVES

The aim of the study is to determine the scale of interregional migrating patients' hospitalizations in Poland in 2013-2017, as well as their demographic and medical factors, total costs and time changes.

MATERIAL AND METHODS

Data from the NHF (National Health Fund) regarding hospitalizations in a given province of patients registered in another province in Poland in 2013-2017 were statistically analyzed. Times series analyses as well as coefficients of correlation, determination and variation were used.

RESULTS

The number of patients hospitalized outside their regional registration and the cost of their hospitalization increased from year-to-year during 2013-2017. There was a large variation in provinces in terms of inflow of patients and costs of their hospitalization, while there was only a small variation in terms of outflow of patients and costs of their hospitalization in the analyzed years. Among the patients hospitalized outside the province where they were registered, there were more women then men, while the age group was dominated by 60-year-olds and their share in the subsequent years increased, while the share of other age groups remained unchanged or decreased. The most and increasingly more from year-to-year hospitalizations outside the regional registration were due to neoplasms and diseases of the circulatory system.

CONCLUSIONS

The results of the study may significantly contribute to the proper planning of securing the health needs of the inhabitants of particular regions, and to improving the quality and economic efficiency of health services in individual NHF branches.