A seasonal chigger-borne disease surveillance program was established at Geoje in March, April, October, and November, 2023. Three species of 45 wild rodents were collected by using Sherman traps, including Apodemus agrarius (Species Ratio; SR 88.9%), Crocidura spp. (SR 8.9%), Micromys minutus (SR 2.2%) in Geoje, 2023. A total of 2,597 chiggers were collected from three species of the rodents in Geoje. The chigger mites were collected from A. agrarius (Chigger Index; CI 64.9) and C. spp. (CI 0.3) for Geoje. In the collection environments, a total number of 734, 659, 172, 520, and 512 chiggers were collected from a reservoir, a ditch, a rice paddy, a field, and a hill, respectively. In the results of the isolation of Orientia tsutsugamushi from the chigger mites, no pathogens were detected from the DNA of the 62 pools of the mites using a Polymerase Chain Reaction method in 2023.

The purpose of this study was to provide basic information for rational management plans for sustainable conservation and utilization by comprehensive analyzing the flora distributed in Yongchu valley, Changwon-si. The flora of Yongchu valley were summarized as 319 taxa including 93 families, 212 genera, 285 species, 3 subspecies, 6 forms and 25 varieties. The endemic plants were 5 taxa such as Chrysosplenium pilosum var. fulvum, Impatiens koreana, Lespedeza maritima, Thalictrum acteifolium and Weigela subsessilis. The rare plants were 11 taxa including I. koreana, Prunus yedoensis and Magnolia kobus. The specific plants by floristic region were 38 taxa including I. koreana, Jeffersonia dubia., M. kobus and P. yedoensis which are class Ⅴ. The naturalized plants were 11 taxa including Solanum americanum, Aster pilosus, Crassocephalum crepidioides and Cerastium glomeratum and so forth and invasive alien plants among these plants was 1 taxa of A. pilosus. The target plants adaptable to climate change were 8 taxa including Corydalis turtschaninovii of northern plant, I. koreana of endemic plant, and Meliosma myriantha of southern plant.

The vascular system of plants consists of two conducting tissues, xylem and phloem, which differentiate from procambium cells. Xylem serves as a transporting system for water and signaling molecules and is formed by sequential developmental processes, including cell division/expansion, secondary cell wall deposition, vacuole collapse, and programmed cell death (PCD). PCD during xylem differentiation is accomplished by degradation of cytoplasmic constituents, and it is required for the formation of hollow vessels, known as tracheary elements (TEs). Our recent study revealed that the small GTPase RabG3b acts as a regulator of TE differentiation through its autophagic activation. By using an Arabidopsis in vitro cell culture system, we showed that autophagy is activated during TE differentiation. Overexpression of a constitutively active RabG3b (RabG3bCA) significantly enhances both autophagy and TE differentiation, which are consistently suppressed in transgenic plants overexpressing a dominant negative form (RabG3bDN) or RabG3bRNAi (RabG3bRNAi), a brassinosteroidinsensitive mutant bri1-301, and an autophagy mutant atg5-1. Wood (called secondary xylem) is the most abundant biomass produced by land plants including Populus and Eucalyptus, and therefore is considered to be one of the most cost-effective and renewable bioenergy resources. In an attempt to enhance xylem differentiation and thus to improve biomass traits in poplars, we generated transgenic poplars overexpressing the RabG3bCA form. As notable phenotypes, both stem height and diameter were increased and xylem area in vascular bundles was significantly expanded in RabG3bCA transgenic poplars compared to control plants. Taken together, these results demonstrate that RabG3b regulates xylem differentiation in both Arabidopsis and Populus. This study enhances our understanding of biological mechanisms underlying wood formation and serve as a framework to engineer the quality and quantity of wood as useful biomass.

An Arabidopsis small GTPase, RabG3b, was previously characterized as a component of autophagy and as a positive regulator for xylem development in Arabidopsis. In this work, we assessed whether RabG3b modulates xylem-associated traits in poplar in a similar way as in Arabidopsis. We generated transgenic poplars (Populus alba x P. tremula var. glandulosa) overexpressing a constitutively active form of RabG3b (RabG3bCA) and performed arrange of morphological, histochemical, and molecular analyses to examine xylogenesis. RabG3bCA transgenic poplars showed increased stem growth due to enhanced xylem development. Autophagic structures were observed in differentiating xyelm cells undergoing programmed cell death (PCD) in wild type poplar, and were more abundant in RabG3bCA transgenic poplar plants and cultured cells. Xylogenic activation was also accompanied by the expression of secondary wall-, PCD-, and autophagy-related genes. Collectively, our results suggest that Arabidopsis RabG3b functions to regulate xylem growth through the activation of autophagy during wood formation in Populus, as does the same in Arabidopsis.