Preparation Of Carrot Explants 1.) Wash carrot taproots in warm, soapy water. Break or cut carrot taproots into pieces 7 cm or less in length. Be careful not to touch surfaces newly exposed by cutting. 2.)Place carrot sections into a suitable, sterile container, cover and set aside. 3.)Transfer the taproots to sterile petri dishes into which a few drops of 70% ethanol or isopropanol have been added. 4.)Obtain a cork borer which has been immersed in 70% ethanol or isopropanol. Allow the excess alcohol to drip off and push the cork borer into the taproot, turning it several times to free the core. Note: Cores should be sampled from the region outside the central core of the taproot. 5.)Remove the cork borer from the taproot and using a sterile applicator, push the core into a sterile petri dish. Cover the dish and set aside until all cores have been collected. 6.)Repeat steps 4 and 5, making sure to place each core into its own sterile petri dish. Note: All tools for handling and dissection of carrot taproots should be immersed in 70% ethanol or isopropanol. 7.)Remove scalpels and forceps from alcohol, allow alcohol to drip off, and dip in sterile water. Using a scalpel, remove 1 cm from each end of the cores and discard the removed ends. Cut the remaining core pieces into 2 mm to 4 mm cross sections, cover and set aside until all cores have been sectioned. Clean tools and return them to alcohol. 8.) Remove forceps from alcohol and dip in sterile water. Aseptically transfer taproot core cross sections to callus initiation medium using forceps. 9.)Cover and seal petri dishes. Store at room temperature away from direct light. 10.)Observe over several weeks, checking for contamination, until calluses are ready for transfer to shoot development medium.