DNA injection through coleoptile; a choice to overcome species barrier and bring about rapid expansion of gene pool in rice.
Ho Un-Hyang UH, Choe Yong-Il YI, Song Sam-Rang SR, Kim Kang K et al.
Selection and breeding of rice varieties depend on genetic diversity contained in the primary and secondary gene pools. So far, researches on introduction of total DNA by means of pollen tube pathway method, ovary injection, seed sink method, ion beam mediated transformation method so as to contribute to expansion of gene pool have been reported in rice. In this study, we injected millet DNA into primary leaf-drawn coleoptile surrounding shoot apical meristem so that we could introduce foreign DNA more easily and not to disturb growth of rice. In the following generations, we selected strain MR-4 exhibiting shortened growth period and more tillers. Although MR-4 exhibited short growth period than DNA recipient, Sohaechal 16, its yield was not significantly different from DNA recipient apparently due to more tillers. RM marker analysis indicates apparently homozygous integration of donor millet DNA in MR-4 genome. Total DNA introduction through rice coleoptile could overcome species barrier and expand gene pool rapidly, thus contributing to the development of rice germplasms with increased abiotic stress tolerance and higher yield.