Other noteworthy features of P. croceum are a high number of full-length ABC-B transporters and a diverse set of half-size ABCB6 genes. Three P. croceum ABC genes were significantly induced during mycorrhiza formation: full-length ABC-B (ABCB2) transporter, half-size ABC-B transporter (ABCB6), and a half-size ABC-G transporter (ABCG6) (Table 3; Additional file 6) [12].