Table 1 Different categories of small RNAs from HT and HS broccoli under heat stress

All read

27,069,903 (100.0 %)

9,459,174 (100.0 %)

26,253,036 (100.0 %)

9,743,157 (100.00 %)

Matched to Brassica rapa genome

19,365,028 (71.5 %)

6,090,652 (64.4 %)

18,657,531 (71.1 %)

6,273,570 (64.4 %)

Matched to Brassica EST

23,322,757 (86.2 %)

7,533,369 (79.6 %)

22,610,232 (86.1 %)

7,759,418 (79.6 %)

Non-coding RNAs (rRNA, tRNA, etc.)

3,325,500 (12.3 %)

225,054 (2.4 %)

2,591,009 (9.9 %)

219,386 (2.3 %)

Known miRNAs

1,098,316 (4.1 %)

16,065 (0.2 %)

854,848 (3.3 %)

16,527 (0.2 %)

Candidates for novel miRNA prediction

19,973,881 (73.8 %)

7,303,071 (77.2 %)

19,983,768 (76.1 %)

7,534,627 (77.3 %)

Unannotated RNAs

2,675,273 (9.9 %)

1,379,348 (14.6 %)

2,603,298 (9.9 %)

1,420,384 (14.6 %)