Rhizopus microsporus
| Authors |
Tiegh. 1875 |
| Strain |
15025 |
| Classification |
Mucorales, Mucoraceae, Rhizopus |
| Culture collection |
BCRC FU31239 |
| Detection frequency |
Low |
| Figure |
 Fig. 1 5-day-old colony on PDA  Fig. 2 Rhizopus microsporus. a–d. Rhizoid, sporangiophores and sporangia. e. Sporangiospores. f. Chlamydospores (Bars= 5 μm, unless otherwise specified) |
| Colonies |
Colonies on PDA grow rapidly, attaining 85-mm in 5 days at 28°C, cottony, elevated, with undulate margin, initially white, turning grey with sporulation, reverse white to pale brown. |
| Sporangiophores |
Sporangiophores born on stolons, slightly swollen near the base, often in groups of 2–4, dark brown, paler towards the apex, 250–400 µm long, 8–15 µm wide. |
| Columellae |
Columellae globose to subglobose, pale brown, 40–65 µm in diam. |
| Apophyses |
Apophyses short, 2–10 µm. |
| Sporangiospores |
Sporangiospores globose to suglobose, smooth or slightly echinulate, subhyaline, 4–5 µm (avg. 4.6 µm) in diam. |
| Chlamydospores |
Chlamydospores abundant on OA after 2 wks, globose or subglobose, hyaline, intercalary, up to 25 µm in diam. |
| Pathogenicity |
This species has been reported to cause rice seedling blight, and the main virulence factor is a phytotoxin called rhizoxin (Sato et al., 1983). Partida-Martinez & Hertweck (2005) found that the phytotoxin was not produced by Rhizopus microsporus itself, but by its endosymbiotic bacteria Burkholderia spp. |
| Specimens examined |
Taiwan, Taichung City, rice grains (cultivar Taichung Native 1), Feb 2015, Jie-Hao Ou, 15025 |
| ITS |
ACTTTACTGGGATTTACTTCTCAGTATTGTTTGCTTCTATACTGTGAACCTCTGGCGATGAAGGTCGTAACTGACCTTCGGGAGAGACTCAGGACATATAGGCTATAATGGGTAGGCCTGTTCTGGGGTTTGATCGATGCCAATCAGGATTACCTTTCTTCCTTTGGGAAGGAAGGTGCCTGGTACCCTTTACCATATACCATGAATTCAGAATTGAAAGTATAATATAATAACAACTTTTAACAATGGATCTCTTGGTTCTCGCATCGATGAAGAACGTAGCAAAGTGCGATAACTAGTGTGAATTGCATATTCGTGAATCATCGAGTCTTTGAACGCAGCTTGCACTCTATGGATCTTCTATAGAGTACGCTTGCTTCAGTATCATAACCAACCCACACATAAAATTTATTTTATGTGGTGATGGACAAGCTCGGTTAAATTTAATTATTATACCGATTGTCTAAAATACAGCCTCTTTGTAATTTTCATTAAATTACGAACTACCTAGCCATCGTGCTTTTTTGGTCCAACCAAAAAACATATAATCTAGGGGTTCTGCTAGCCAGCAGATATTTTAATGATCTTTAACTATGATCTGAAGTCAAGTGGGACTACCCGCTGAACTTAA |