Germination and seedling growth
- Rice (Oryza sativa L. japonica cv. Nipponbare) seeds were sterilized with 70% Et-OH and 1% hypochlorous acid, and imbibed in distilled water.
- The germinated seeds were transplanted in a mesh floating in distilled water and grown in a growth chamber at 28ºC, 24 h light and 60% humidity.
- After 3 days of germination, the seedlings were transferred in culture medium consisting of Yoshida’s nutrient solution diluted 5x and adjusted to pH5.5 using 1mM-MES and 1N-NaOH. The seedlings were allowed to grow for another 4 days. The culture medium was renewed every 2 days.
- Seven-day old seedlings were transferred in culture medium containing the plant hormone.
Treatment
| Plant hormones | Hormone treatment | Mock treatment | |
|---|---|---|---|
| Abscisic acid | (±)Abscisic acid(ABA) | 50μM (±)ABA + 0.1% Ethanol | 0.1% Ethanol |
| Gibberellin | Gibberellic acid 3(GA3) | 10μM GA3 + 0.1% Ethanol | 0.1% Ethanol |
| Auxin | Indole-3-acetic acid(IAA) | 10μM IAA + 0.1% Ethanol | 0.1% Ethanol |
| Brassinosteroid | Brassinolide(BL) | 1μM BL + 0.1% Ethanol | 0.1% Ethanol |
| Cytokinin | trans-Zeatin(tZ) | 1μM tZ + 0.02% DMSO | 0.02% DMSO |
| Jasmonic acid | (±)Jasmonic acid(JA) | 100μM (±)JA + 0.02% DMSO | 0.02% DMSO |
Sampling
Shoot samples were collected at 0 min (pretreatment), and at 1 h, 3 h, 6 h and 12 h of incubation after hormone treatment.
Root samples were collected at 0 min (pretreatment), and at 15 min, 30 min, 1 h, 3 h and 6 h of incubation after hormone treatment.