In Vitro Culture of Rudimentary Embryos of Eleven Ilex Species1

Abstract

Abstract The heart-shaped embryos, dissected from mature fruits of 11 Ilex (holly) species in 4 taxonomic sections, grown in modified White’s and Linsmaier and Skoog’s media jelled with Bacto-agar, produced seedlings. The rudimentary embryos were sufficiently autotrophic that a carbon source was the only organic compound needed in the media. There is a great variation in speed of in vitro development among individual embryos of the same species. The average embryo length of I. aquifolium L. increased linearly and most embryos reached germination size at the 55th day of incubation. The average embryo length of I. cornuta Lindl. increased sigmoidally and most embryos reached germination size at the 23rd day of incubation. The in vitro germination percentages for most species were above 80%. The survival rates after transplanting were higher than 75%. Sub-sequent seedling growth in greenhouses was healthy and vigorous.