Notes on Sweet orange (Citrus sinensis L. Osbeck) populations’ divergence: Landscape genetics, comparative phylogeny, and Niche modeling

Abstract

Abstract Sweet orange is one of the economically important plant species. The present study was conducted with the aim of generating genetic diversity data in Iranian sweet orange germplasm and investigating the landscape genetics of these plants in order to identify genetic regions compatible with environmental and climatic variables using SCoT molecular marker on 29 cultivars. The obtained results showed low to moderate genetic diversity in the sweat orange populations and indicated that the orange germplasm contains a complex genetic group of closely related individuals, but probably to some extent due to local breeding practices and artificial selection by orchard management. It is genetically differentiated. Also, some genetic kidneys were identified, especially in the southern regions of Iran. We also identified genetic regions that are significantly associated with environmental and climatic variables that can be used in the sweet orange conservation program in the country. This is especially true for the studied orange plants from southern Iran. The present study showed that global and local spatial variables affect the genetic structure of orange populations, and orange populations are separated by the phenomenon of distance, that is, as the geographical distance of the studied populations increases, the genetic distance increases. The analysis of species distribution modeling in the present study showed that both northern and southern regions of Iran are suitable habitats for orange cultivation, while temperature and precipitation are both important climatic factors for the cultivation and propagation of orange plants.