Polyploidy Creation Based On Somatic Embryogenesis In Two Lilium Species Native To China

Lilium pumilum DC.Fisch and Lilium davidii var.unicolor belong to the wild Lilium which own bright flowers and strong tolerance.But their weakness including growth dwarfed and small flowers limit the applications.Colchicine was used to induce the polyploidy of two lilium based on the somatic embryogenesis in this study.The namount of chromosomes was used to identified the Polyploid,and we also analyzes the bands of ISSR,size and density of stoma and the contents of chlorophyll in tetraploid to obtain new species with good cultivation characteristics.The main results are showed as follows:1-Polyploidy induction and ploidy determination in Liliumpumilum DC.Fisch.The polyploidy induction was carried by colchicine,and the explants were the scales and embryonic callus.Two methods were used and compared.Polyploid plants were obtained by immersing the explant in various concentrations of colchicine and linoculating explant in the mediums containing colchicine.Ultimately,we obtained 53 polyploid plants including 19 tetraploids(bulbs biger and stronger)from 267 regenerated plants.Based on the survival condition of regeneration plants and induction rate,we think that the way of immersing embryonic callus was better.It was most effectively induced by immersing embryonic callus in 0.1%colchicine solution for 1day.2.Polyploidy induction and ploidy determination in Lilium davidii var unicolorWe used the best inducing treatment of Lilium pumilum DC.Fisch.(immersing embryonic callus in 0.1%colchicine solution for lday)to induce the Lilium davidii var.unicolor.Ultimately,we obtained 28 polyploid plants including 6 tetraploids(bulbs biger and stronger).3.ISSR analysis of somatic embryos and polyploid plants in LiliumAmong the 20 different tested ISSR primers,8 primers selected respectively in Lilium pumilum DC.Fisch.and Lilium davidii var.unicolor which produced distinct bands.The genetic fidelity of regeneration plants via somatic embryogenesis was analyzed using the 8 primers.Polymorphic bands were not observed from the agarose gel data among the 3270 bands,and we determined the process of somatic embryogenesis in Lilium pumilum DC.Fisch.and Lilium davidii var.unicolor was relatively stable.At the same time,ISSR technology was also used to the genetic analysis between 2X and polyploids in the aspect of molecular level.Total of detected bands was 336 and the percentage of polymorphic bands was 14.58%in Lilium pumilum DC.Fisch.Total of detected bands was 318 and the percentage of polymorphic bands was 9.75%in Lilium davidii var.unicolor.Results show that the artificial inducement leading to the genetic alteration in plants.4.Morphological and cytological identification of tetraploid and diploid plantlets in Lilium pumilum DC.Fisch.and Lilium davidii var.unicolorTetraploid plantlets of Lilium were showed big bulbs and broad leaves in dark green.Tetraploid plantlets was living and growing after transplanting,and there was significant difference in appearance compared with diploid plantlets.The length of stoma and guard cell in tetraploid plantlets were all greater than them in diploid plantlets.Stomata in tetraploid plantlets were less than diploid plantlets per unit of area.Besides,the content of chlorophyll was higher tetraploid plantlets.In conclusion,tetraploids that induced by colchicine and own excellent properties were obtained in this research.These tetraploids had important implications for new germplasm cultivation in two wild lilies.