Coelogyne Flaccida Case Study

Coelogyne flaccida seed culture in vitro reveals that there are two pathways of asymbiotic seedling development from seeds. On one pathway, the seeds obtained from green capsules germinated readily asymbiotically in the nutrient medium supplemented with 0.5 – 2 mg/l NAA and IAA plus 15% coconut water and charcoal, 2 gm/l. During the usual germination process, the undifferentiated embryo of the seed produces a large number of protocorm-like bodies (PLBs) without forming the intermediate callus tissue. This is called non‐clonal propagation because of all the PLBs were derived from the fusion product (via zygote and embryo) of the two opposite reproductive units (pollen and egg cells) containing the genome made of genetically recombinant chromosomes …show more content…
It has also been used to assess the levels and patterns of genetic diversity and the genetic stability and the degree of genetic diversity [43]. The results of peak profile of F–RAPD and F–ISSR confirms that Coelogyne plants micropropagated using seeds as explants maintain their own genetic variability present in the cells of the zygotic embryo of the seeds. Zygotic cells contain the genomes which are the product of meiotic recombination and fertilization between two opposite reproductive cells. So, all cells of the zygotic embryo are not genetically identical. Meiotic recombination shuffles the genes between the two chromosomes in each pair (one received from each parent), producing recombinant chromosomes with unique genetic combinations. This gene reshuffling during meiosis has a significant influence on the creation of genetic diversity among the plants obtained from seed germination. The peak profiles of F–RAPD and F–ISSR of Coelogyne plants micropropagated from secondary PLBs as explants show genetic stability (as F-RAPD & F-ISSR peaks are more or less identical. So, those are not shown), even after a prolonged period of 112 days, under the effects of growth regulators, such as BAP and NAA, and under stressful conditions during in vitro culturing [44]. The regenerants derived from direct clonal multiplication of secondary PLBs were genetically identical which indicates that they had retained their own characteristics due to the vegetative multiplication of individual secondary PLB and did not show molecular changes relative to each other. The transfer of the same characters from plant to plant appeared in the form of monomorphic bands. Meiotic recombination is a process that increases genetic diversity among individuals of sexually reproducing species. Genetic diversity plays an important role in the survival and adaptability