Frequency of ectomycorrhiza in black cherry (Prunus serotina Ehrh.) and common cherry (Prunus padus L.) growing in the immediate vicinity

Although alien tree species have been studied for many years, it is still unclear why some of them become invasive. The establishment of mycorrhizae is considered a factor influencing invasion success. This study aimed to compare the frequency of mycorrhizae in the roots of the foreign and invasive black cherry and the native common cherry, which are related. The frequency of ectomycorrhizae was assumed to be higher in common cherry (Prunus padus) than in black cherry (Prunus serotina). Thirty 2–3-year-old trees (15 P. serotina and 15 P. padus) were collected from stands where they grew next to each other. Samples were collected in June 2022 from the Forest Experimental Station of Siemianice, Złotówek, and Mrowino. The presence of mycorrhizal fungi was assessed. Morphotypes of ectomycorrhizae were determined with a stereoscopic microscope. The average mycorrhizal frequency was calculated. The roots were scanned and determined with the WinRhizo image analysis system. The length, surface area, diameter, volume, and number of root tips were determined. Statistical analysis of the obtained results was performed with Statistica v.13. The laboratory analyses indicated the dominance of morphotype 3 in all the examined roots of common cherry and black cherry. The highest proportion of type 3 mycorrhizae was found in common cherry at each location. This study showed that black cherry can form ectomycorrhizal associations, which probably positively influenced the success of its invasion.