Direct Somatic Embryogenesis From Bublet Thin Cell Layers Of Lilium And Assessment Of Genetic Stability In Regenerants By ISSR

Lily, a monocot belonging to the Liliaceae, is one of the most important cut and pottedflower crops in the world. However, genetic improvement of lily cultivars by conventionalbreeding is severely limited due to their high heterozygosity and crossing incompatibilityamong the lily species. In vitro culture techniques provided alternative to conventionalmethods. Availability of in vitro plant regeneration is helpful for genetic improvement by invitro culture techniques. Somatic embryogenesis is preferred, because it has high regenerationrate and can avoid chimeras formation. The objective of the present study was to develop awidely applicable procedure for somatic embryogenesis and to assess the genetic stability ofthe regenerants by using ISSR markers.The results showed when cultured on MS medium supplemented with0.1mg L-1NAAand0.1mg L-1KT, TCLs (0.8mm in thickness) of Lilium longiflorum×Oriental hybrid‘Triumphator’ developed yellow, friable, granular callus after6weeks of culture in the dark. Amultiplication medium containing1mg l-1NAA and0.2mg l-1TDZ was found optimal forcallus proliferation. These calli further formed somatic embryos and germinated into wholeplantlets after transferred onto MS medium free of hormones. This procedure was furthertested for extra four Lilium species and hybrids. The results showed that the highest (85.0%)and the lowest (25.0%) induction rates of embryogenic callus were found in Liliumlongiflorum and Lilium davidii var. unicolor, with an average rate at51.3%obtained for theseLilium tested. Genetic stability of the regenerants of Lilium longiflorum×Oriental hybrid‘Triumphator’ was assessed by ISSR. Out of the40ISSR primers primers initially screened,8produced strong, clear, reproducible bands. Assays with these eight primers generated47scorable bands, ranging from250to1200bp in size. A total of1410bands were generatedand on polypholism was found.Sucessful establishment of the widely applicable procedure for somatic embryogenesisprovided an efficiently technical platform for micropropagation, genetic transformation,production of artificial seeds and cryopreservation of Lilium.