Provided is a method of improving plant embryo development and/or germination. The method comprises developing plant embryos in the presence of nitric oxide (NO). The method entails the step of incubating plant embryogenic suspensor mass (ESM) in, or on, a development medium containing a nitric oxide donor for a period of time to develop mature somatic embryos. The method disclosed herein improves the yield and/or the germination frequency of plant embryos as compared to plant embryos developed by conventional methods without a nitric oxide donor in the medium.
