Table 4. Diversity indexes of the microbial collection.

Diversity Index(OTUs 99%)	E	R	S	B
Taxa	9	12	15	10
Individuals	77	74	73	75
Dominance	0.262	0.252	0.240	0.372
Shannon	1.586	1.799	1.930	1.429
Simpson	0.738	0.748	0.760	0.628
Evenness	0.543	0.504	0.459	0.417

The indexes were calculated for the sequences of bacterial strains isolated from the different fractions of the pepper root system and the non-cultivated arid soil. Sequences have been grouped in OTUs based on nucleotide similarity at 99%.