The present invention relates to new methods of selecting and breeding organisms, in particular organisms which exhibit symbiotic behavior with symbionts such as fungal endophytes or epiphytes or bacterial microbiome in plants, and to new organisms and symbiota developed thereby. More particularly, the present invention provides artificial seeds comprising symbiota, and methods for preparing and using such artificial seeds, as well as plants, plant seeds and other plant parts derived from artificial seeds or symbiont-containing plants of the present invention.