3.3 Richness of endophytes
The average taxon richness at species level of endophytic fungi in the whole fungal communities across control and three radiation levels was 127.30 ± 29.21. Richness of endophytic fungi in aerial tissues was 150.60 ± 12.90 and in roots was 104 ± 21.01. Two-way ANOVA indicated that tissue origin significantly influenced the richness of endophytic fungi (p < 0.001). T-test showed that the fungal richness was significantly more in aerial tissues than in roots (df = 31.543, p < 0.001). In contrast, the bacterial richness was significantly less in aboveground parts than in belowground parts (df = 30.122, p < 0.001). The richness of endophytic bacteria across control and three radiation levels was 163.60 ± 27.95 in aerial tissues, while it was 252.90 ± 49.15 in roots. Two-way ANOVA showed that both the tissue types (p < 0.001) and its interaction with radiation level (p = 0.029) significantly affected the richness of endophytic bacteria.
The richness of endophytic bacteria and fungi in aerial tissues was similar among the control and three radiation levels (Fig. 2). In addition, the richness of endophytic fungi in roots was the same among the different radiation levels while the richness of endophytic bacteria at low radiation level was significantly higher than that in control (Fig. 2).