Identification of Fusarium oxysporum f. sp. raphani and investigation on fusarium wilt development by isolates and inoculation methods were conducted to establish a screening method for fusarium wilt-resistance in radish (Raphanus sativus L.) germplasm. Pathogenicity of F. oxysporum f. sp. raphani isolate, Heonggye-1 and Heonggye-2, to radish plants was confirmed by seedling test. Radish seedlings were inoculated by root-dipping and soil-drenching with or without root-wounding. For Heonggye-1 isolate, mean disease indexes were 4.13 and 3.91 by root-dipping and soil-drenching with root-wounding, respectively, but those were 1.87 and 1.88 without root-wounding. For Heonggye-2 isolate, mean disease indexes were 3.83 to 4.37 regardless of inoculation methods. Two-hundred sixty accessions of radish germplasm collected from 9 countries of Asia and Europe were evaluated for fusarium wilt-resistance by soil-drenching with root-wounding with Heonggye-2 isolate. Fifty-four resistant accessions with higher than 70% of the percentage of resistant seedlings in accession (PR) and lower than 20% of the percentage of susceptible seedlings in accession (PS) was found. Eighteen susceptible accessions with lower than 20% of PR and higher than 50% of PS were selected. These accessions could be used as breeding and research materials after re-evaluation of disease-resistance and characterization of agronomical traits.
We investigated the effect of pre and post-cryopreservation treatment on the dehisced Ginseng (Panax ginseng C.A. Meyer) seeds germination rate. All seeds covered with endocarp and 96.3% of them were opened, initial moisture content (IMC) and germination rate were 55.9% and 84.0%, respectively. According to the pre and post-cryopreservation methods, highest seeds germination rate (GR) was observed in non-precooled seeds which recovered at 40°C, in which MC was 8-12% and desiccated at 15°C. However, by prolonged drying the seeds GR comparatively decreased under MC of below 2.2%, reaching below rate 4% regardless of pre and post- cryo treatments, whereas the seeds dried at 25°C airflow cabinet saved significantly high rate. The effects of desiccation and of cryopreservation on the survival and developmental pattern of roots and stems showed that the earliest appearance of the root in control seeds was detected after 10 days of bedding in GA medium, and the stem started to develop later on the third week of germination test. And, on the 30th day of the investigation stem growth rate significantly increased and showed equivalent data with root rate. Almost the same pattern showed the seeds after cryopreservation, but it significantly delayed in the development compared to control, where term of the investigation continued till 40 day than control 30 day. Additionally, non-precooling seeds in both desiccation and recovery methods were showed high root and stem growth compared to precooled treatments.