Elementary plant Biochemistry and Biotechnology (2+1)

Shoot tip grafting (STG) /Micrografting

Shoot tip grafting (STG) /Micrografting

• In a number of species including those of citrus peach and apple attempts at meristem culture remained unsuccessful in virus elimination. As an alternative, shoot tips of 0.14-0.18 mm in length isolated aseptically from a diseased plant were grafted on to young etiolated root stock seedlings grown in vitro.

Virus Indexing

• The biological assays are reasonably accurate, but too slow and difficult. Alternatively, techniques involving electron microscope, use of indicator plants, serology or a combination of both were developed for virus detection in plant tissues. Among serological techniques, enzyme linked immunosorbent assay (ELISA) and nucleic acid hybridization techniques are popular.
Examples for Plant species for which virus free plants produced through meristem tip culture

Plant species	Virus eliminated
Allium sativum	Garlic Mosaic Virus
Brassica oleracea	Cauliflower Mosaic Virus
Dahlia spp.	Complex viruses
Glycine max	Soybean mosaic virus
Musa spp.	Cucumber mosaic virus
Nicotiana tobaccum	Tobacco mosaic virus