Types of Embryo Culture in Plants

Hybridization

• Hybridization allows scientists to transfer mutant alleles between the embryos of two plant species. The process of interspecies crossing introduces new genetic combinations to the embryo plants. Scientists can also use chromosome-doubling techniques with an embryo culture crating a new polyploid species.

Somatic Embryogenesis

• Somatic, or asexual, embryogenesis uses use embryo cultures and somatic plant tissues for creating whole plants. The production of somatic plant embryos occurs directly or indirectly. In the direct process, scientists create an embryo directly from a small group of cells or a single cell without the use of an intervening callus, a group of additional undifferentiated plant cells. Oxford University Press states that the direct process is rarely used. With indirect somatic embryogensis, the explant, a group of isolated plant cells, produces a callus. Scientists then use the callus tissue or cells to produce embryos.

Microspore Culture

• Scientists use plant anthers or pollen as an explant creating an in vitro embryo and callus that has haploid tissue. Generally, pollen contains microspores, which are male gametophytes. To create additional embryo plant cultures in vitro from the haploid tissue, scientists use the somatic tissues of plant anthers acting as an explant. The spontaneous opening of the mature anther structure helps produce embryos that are pollen derived. Another method of creating an embryo microspore culture is through the culturing of plant anthers in a liquid medium. The pollen the anther releases can form embryos, which scientists use for assisting plant regeneration.

Germination

• An individual may use immature plant embryo cultures to help grow hybrid or unripe seeds that failed to germinate. In the book “Introduction to Plant Tissue Culture,” M.K. Razdan states that using this type of embryo culture to produce plants is difficult and requires the use of a, “complex nutrient medium,” and using an excised embryo that at the ideal developmental stage. Using mature embryos in cultures created from ripe seeds helps prevent, “inhibition in the seed,” regarding germination. Razdan states that it is easier to use mature embryos for the germination process because the developing embryos require a simpler nutritional supplement made of sugar, mineral salt and agar.