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Rice (Oryza sativa L.) is an important crop for advanced life support, but the height of even full-dwarf cultivars (80-cm tall) has made them difficult to use in controlled environments. We identified a rice mutant that lacks 3ß-hydroxylase, the enzyme responsible for conversion of gibberellic acid 20 (GA20) to GA1 (Murai et al., 1990; Honda et al., 1996). GA1 is the active form of GA in most plants, so this rice variety is extremely short (20-cm tall). ‘Super Dwarf’ rice has a higher harvest index (50%) and similar yield to the commonly used rice cultivars ‘Ai-Nan-Tsao’ and ‘29-Lu-1' and its parent line ‘Shiokari’ (Kinoshita and Shinbashi, 1982). Uniform stand establishment is critical with small research plots. It is therefore important to determine procedures for optimum germination.