Foreign DNA injection through coleoptile leads to fixation of novel traits in rice

Improvements of germplasms in rice, a staple crop on which nearly half the world’s population depends, are usually aimed at increasing yield per hectare and increasing adaptability to environment. In this paper, millet (Panicum maximun) exhibiting high water use efficiency and adaptability to harsh environment was used as DNA donor to increase adaptability of Sohaechal 16, a cultivar belonging to Oryza sativa L. japonica. Total DNA from millet was injected through primary leaf-drawn coleoptile of rice seedlings and 48 RM markers exhibiting polymorphism between rice and millet were used to analyse DNA donor, DNA recipient and postulated T₀ individuals. Out of 972 survivied individuals from 1200 millet DNA-injected seedlings, 17 individuals exhibited only fragments specific to millet on at least a RM loci. MR-11 T₀ individual exhibiting short days to heading and red grain color in contrast to DNA recipient, Sohaechal 16 was selected and propagated. In T₁ and T₂ generation, Strain MR-11 didn’t exhibit segregation in the context of days to heading and grain color and had fragments specific to millet (DNA donor) on 5 RM loci. These results suggest possibility of obtaining rice germplasms with novel fixed traits by introducing DNA of other species through coleoptile and would contribute to reveal QTL related with growth period and grain color in rice.