Flooding stress causes a significant reduction in soybean yield. The development of flood-tolerant cultivars is an effective way to minimize yield loss due to flooding. Information on candidate genes for flooding tolerance is useful for developing tolerant lines. The
objective
of this study was to identify potential candidate genes for flooding tolerance in soybean by integrating the results of a quantitative trait locus analysis and RNA sequencing. A total of 19 genes showed good amplification in capillary electrophoresis and were further analyzed through a reverse transcription quantitative polymerase chain reaction (qRT-PCR); two of these genes showed differential expression among tolerant and susceptible lines. The expression of Glyma.12g030900 and Glyma.10g050300 in leaf and root tissues, respectively, was higher in several tolerant lines than in the susceptible lines under flooding stress. The chlorophyll index of the tolerant lines was also consistently higher than that of the susceptible lines over two years, supporting the qRT-PCR results. This study provides useful information on flooding tolerance in soybeans.

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 (P_R) and lower than 20% of the percentage of susceptible seedlings in accession (PS) was found. Eighteen susceptible accessions with lower than 20% of P_R 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.