We report a procedure for direct shoot regeneration via leaf segments of Lilium Oriental hybrid ‘Casa Blanca’. The segments were cultured with the abaxial side in contact with a Murashige and Skoog medium containing 0.1 mg • L-1 BA and 0.1 mg • L-1 NAA, 3% sucrose, and 0.8% agar for shoot regeneration. The cultures were incubated for 4 weeks under a 16 hrs photoperiod at 23 ± 2oC for adventitious shoot regeneration. With this procedure, a mean shoot regeneration frequency of 88-90% and a mean number of shoots of 2.5-3.6 per segment were obtained. Ploidy analysis of the regenerated plants using flow cytometer revealed the same ploidy level (diploid) with mother plant. This study will be used for large-scale multiplication and genetic transformation system in lily.

An efficient shoot regeneration condition for pea cv. ‘Sparkle’ was developed by using optimum explant, plant growth regulator concentrations, and pretreatment of BA onto explant. The average shoot number per explant showed the highest on two kinds of shoot induction media (MSB5 media containing 2 ㎎/L BA and a combination of 2 ㎎/L BA and 1 ㎎/L TDZ) when cotyledonary node explants were cultured. Moreover, the pretreatment of explant in 200 ㎎/L BA solution was found to be more effective in shoot induction than that of non-pretreatment. By histological study, cell division and proto-meristem were formed near the surface of the sub-epidermal and epidermal cell layers of cotyledonary node in earlier than 3 days after culture. The analysis of genetic stability of regenerants by using thirteen ISSR markers showed that in vitro regenerated plants showed polymorphism with 8.3% compared with their mother plants.

Twenty apple germplasm accessions from the Korean Genebank were successfully cryopreserved using two-step freezing to back up genetic resources maintained by field collections. This study examined the morphological and genetic stability of cryopreserved dormant apple buds that were stored in liquid nitrogen, and then rewarmed and regrown. Whole plants were regenerated directly from dormant buds through budding without an intermediary callus phase. The cryopreserved buds produced high levels of shoot formation (76.2-100%), similar to those of noncryopreserved buds (91.3-100%), with no observed differences between cryopreserved and noncryopreserved materials. Three of the twenty cryopreserved apple germplasm accessions were used to assess morphological and genetic stability. No differences in morphological characteristics including shoot length, leaf shape, leaf width/length ratio, and root length were observed between controls (fresh control and noncryopreserved) and cryopreserved plantlets. The genetic stability of regenerants (before and after cryopreservation) was investigated using inter simple sequence repeat (ISSR) markers. The ISSR markers produced 253 bands using four primers, ISSR 810, SSR 835, ISSR 864, and ISSR 899. These markers showed monomorphic banding patterns and revealed no polymorphism between the mother plant and regenerants before and after cryopreservation, suggesting that cryopreservation using two-step freezing does not affect the genetic stability of apple germplasm. These results show that two-step freezing cryopreservation is a practical method for long-term storage of apple germplasms.

Common buckwheat has the sporophytic self-incompatibility mechanism and that’s why it has the ability to cross pollinate between two plants with different styles (thepin type and thrum type). The S supergene is thought to govern self-incompatibility, flower morphology and pollen size in buckwheat. Already, we have produced self-compatible buckwheat lines by an interspecific hybridization between Fagopyrum esculentum and F. homotropicum by embryo culture. The pollen size of F1 plants produced by a cross between a pin type plant and the self-compatible plant was similar to that of the self-compatible lines and segregated together with flower morphology without exception. The pollen tubes of the self-compatible plants were compatible with styles of the pin plants but incompatible with the styles of thrum plants. But, the pollen tubes of thrum flowers were compatible with the styles of self-compatible plants. Also, the pollen tubes of pin flowers were incompatible with the styles of self-compatible plants. Already, from these results, we have reported a tentative genotype for heterostyle and homostyle flower types. Homomorphism was controlled by a single allele Sh, while the pin/thrum-complex gene was governed by a single genetic locus S, with two alleles, S and s, which control Ss (thrum-type) as well as the ss (pin-type), respectively. Corresponding represents the case of a single locus S with three alleles, Sh, S and s, and the phenotypes, homomorphic, pin and thrum. It can be characterized by relationship of dominance, S>Sh>s. Using the two self-fertile lines, one is considered as the long-homostyle flowers and the other is considered as the short homostyle flowers. If the short-homostyle trait had arisen by recombination in the S supergene, its genotype would be considered to be GIs ip a/GIs ip a. The pollen tubes of the short-homostylous plant should be compatible with the styles of thrum plants. Also, the pollen tubes of short-homostylous plants should be incompatible with the style of long-homostylous plants, and the reciprocal cross also should be incompatible, because the genotype of long homostyle is gis Ip PA/gis Ip PA. Furthermore, the flower morphology of F1plants produced by the cross between cross and short homostyle flowers should be thrum or short homostyle and only short-homostylous plants should be produced by the cross between pin and short homostyle flowers. However, the compatibility or incompatibility of short homostyle flower was not clarified. So, we need to clarify the compatibility or incompatibility of the style of short homostyle flowers for the next step.

The significance of genetic stability and bio-safety environment has been recently recognized by many GM plants. This study was to evaluate the GM stability of transgenic rice and to identify the environment variance. The GM rice of vitamin A　-enriched rice and four check cultivars were analyzed the data on agronomic characters and principal component for 2009-2011 in large-GM crop field. Cultivation environment was conducted in the large-GM field and greenhouse to determine grain characters. In this experiment, there was no significant difference in agronomic characters between GM rice of vitamin A-enriched rice and a donor plant, Nagdong. Related to grain characters, grain appearance and physicochemical characteristics were similar to GM rice of vitamin A-enriched rice and a donor plant, Nagdong. However, grain appearance in GM rice of vitamin A-enriched rice showed to white core and white belly when GM rice of vitamin A-enriched rice was planted in greenhouse. The type and distribution of dominant weed species also were not different from GM rice of vitamin A-enriched rice and a donor plant, Nagdong. Additionally that of gene flow was not detected in dominant weed species by PCR analysis.

An in vtro nucellar polyembryo propagation method was established with mature seed of the Citrus junos Sieb. 7-8 nucellar polyembryos per seed were induced on MS basal medium without plant growth regulators. The polyembryos developed to complete plantlets on teatment with IBA. These shoots grew further in MS medium without plant growth regulators. Rooting of shoots occurred on MS medium supplemented with IBA. These plantlets were successfully transplanted to small plastic pot containing soil mixture. Somatic embryos were induced from nucellar polyembryo and maturation occurred spontaneously from proliferating cultures on MS medium without growth regulators. Random Amplified Polymorphic DNA (RAPD) marker analysis of in vitro and in vivo grown junos orange showed identical polymorphism indicative of their genetic stability. The RAPD polymorphism produced revealed same banding pattern in each regenerant. Hence, propagaton of junos orange by nucellalr polyembryos was efficient and produced in genetically stable plants under in vitro conditions.