Endangered native plant habitats and populations are rapidly disappearing because of climate and environmental changes. As a representative, the abundance of the first-class endangered wild plant, Cypripedium japonicum, has been rapidly decreasing in Korea. The purpose of this study was to evaluate the distribution of rhizosphere and endophytic fungi on C. japonicum in its native habitat. A total of 440 rhizosphere and 79 endosphere fungi isolates were isolated and identified on the basis of their molecular characteristics. Sixty-five genera and 119 fungi species were identified in this study. The genus Trichoderma showed the highest abundance among both rhizosphere and endosphere fungi. Mortierella, Hypocrea, and Penicillium spp. were also relatively dominant species on C. japonicum. The community structures of rhizosphere and endosphere fungi were similar, but endosphere fungi showed greater diversity.

In Korea, Strawberry bacterial angular leaf spot disease was first reported in 2010. The disease of strawberry caused serious problem for strawberry producers and export. To field test, we applied the bactericides in June and October as nursery stage and cultivation stage, respectively. In nursery stage with high temperature condition, Oxolinic acid (97.2%) showed significant control effect. In cultivation stage with low temperature condition is soil sterilization and soil non-sterilization the control effect. In cultivation stage in soil sterilization stage Validamycin (93.3%) showed reliable control effect against the disease. Also, soil non-sterilization stage with low control effect of Validamycin (80%) showed control effect the lower than a soil sterilization stage.

Changes in chromosome number and karyotype evolution are important to plant diversification, as they are both major drivers of speciation processes. Herein, chromosome number, karyotype, and genome size of the Korean lady’s slipper orchid Cypripedium japonicum Thunb., an endangered species, were investigated in natural populations. Furthermore, all cytological data from this species are reported herein for the first time. The chromosome number of all investigated C. japonicum plants was diploid (2n = 2x = 22), with x = 11 as base chromosome number, whereby the species can now be clearly distinguished from the Japanese lady’s slipper orchid. The karyotypes of all studied individuals were of similar length, symmetrical, and rather unimodal. Flow cytometry of the C. japonicum revealed that the genome size ranged from 28.38 to 30.14 pg/1C. Data on chromosome number and karyotypes were largely consistent with previous results indicating that Korean (x = 11) populations of C. japonicum are more closely related to Chinese populations (x = 11) compared to Japanese (x = 10) populations. These comprehensive cytological results will benefit the efforts to discriminate the geographically isolated and endangered Eastern Asian (China, Japan, and Korea) lady’s slipper orchid species.

Rhododendron keiskei var. hypoglaucum (Ericaceae) was recently reported in Korea, with a disjunct distribution on the southern islands of the Korean Peninsula. Although chromosome numbers and ploidy variations are important traits in angiosperms, gaining a clear understanding the cytological features of Rhododendron has been hampered by the small size of its chromosomes. We herein report the chromosome number, karyotype structure, and genome size of R. keiskei var. hypoglaucum for the first time. The chromosome number of the investigated plants was 2n = 26 with x = 13 as the base chromosome number, which is the one of the frequently encountered base chromosome numbers in Rhododendron. The karyotype of R. keiskei var. hypoglaucum is composed of metacentric and submetacentric chromosomes similar in length, which ranged from 1.39 to 2.40 μm. The DNA 1C-value in all examined accessions was small, ranging from 0.63 to 0.65 pg, further supporting the stable genome size in Rhododendron. These comprehensive cytological results provide a framework for detailed molecular, cytogenetic, and phylogenomic analyses that can be used to interpret the slow species diversification rate in Rhododendron.

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