| Plant species |
Androgenic stress |
Stage of responsive pollen grain |
| Brassica napus (rapeseed) |
Heat treatment (32°C for 8 hr)*, gamma-rays, colchicine |
Late unicellular to early binucleate pollen grains |
| Hordeum vulgare (barley) |
Stress by mannitol, calcium and ABA . |
-- |
| Nicotiana tabacum (tobacco) |
Glutamine and sugar starvation (then transfer to high glucose medium) |
Young bicel1ular pollen grains |
| Triticum aestivum (wheat), Oryza sativa (rice), etc. |
Cold treatment (4-10°C for 3-24 days) |
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