• Weed & Turfgrass Science
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• v.2 no.2
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• pp.198-201
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• 2013

This study was carried out to develope new zoysiagrass cultivar Semil' (Registration no. 1749). Artificial crossing between the collected lines of typical Z. matrella, NM1 (collected in South Korea) and the different ecotype of Z. matrella, ASm (collected in South Korea) was made to develop a F1 hybrid plant (NM1 ${\times}$ ASm). Among the 30 progenies, (NM1 ${\times}$ ASm)-1 (Semil) showed superior performance in density rating. 'Semil' showed genetically light green color, with narrow leaf width ($2.7{\pm}0.12mm$), and low plant height ($10.3{\pm}3.7cm$), Length to lowest leaf blade of this cultivar was $1.8{\pm}0.15cm$, which may allow low mowing height upto 12 mm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.239-242
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• 1999

In this study, we evaluates the dependence of thickness and temperature in the breakdown strength of MDPE and effect of semiconductor. As the result, breakdown strength trend to decrease according to the increase of thickness and temperature but there is no dependence of temperature in the 70${\mu}{\textrm}{m}$ MDPE film. We obtained the result that the breakdown strength was a little lower in the structure of Semil/MDPE than Semi/MDPE/Semi, but breakdown strength of MDPE was greater both of all. Therefore we are investigating the effect of semiconductor in the breakdown strength.

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.368-375
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• 2013

Whole genome transcriptomes from Miscanthus species were sequenced and analyzed, which provided 50 different types of transcription factor (TF) involving various developmental processes or environmental stresses. Among the explored TF, WRKY gene family was the major type and one of the WRKY genes, MSIR7180_WRKY4, induced under low temperature environment was selected to investigate how the Miscanthus-originated MSIR7180_WRKY4 TF responds when exposed to low temperature in four warm-season turfgrasses (Z. matrella 'Semil', bermudagrass, St. Augustinegrass, and seashore paspalum). The MSIR7180_WRKY4 was expressed higher during low temperature period in Bermudagrass, but the expression was enhanced in St. Augustinegrass. In contrast, the gene in 'Semil' cultivar was barely expressed and relatively less expressed, but repressed gradually in seashore paspalum, which seems to allow two turfgrasses stay-green longer in the fall season. The results indicate that bermudagrass and St. Augustinegrass adapt to low temperature quickly, but relative tolerance to low or cold temperature at the molecular level needs to be further investigated at different physiological stages and the corresponding genes systematically.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.283-291
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• 2017

Zoysiagrass has been used in Korea as a native grass. Informations on distributions, classifications, breeding efforts and outputs, current production and uses of zoysiagrasses in Korea are summarized. During past a few decades, collection of naturally growing zoysiagrass ecotypes has been continued, followed by evaluation, selection and cross-pollination. Classification efforts using important morphological, biochemical traits and DNA polymorphisms resulted in the several suggestions of grouping zoysiagrass species and varieties. Zoysia japonica consistently form separate group, while Zoysia sinica and Zoysia macrostackya have been separately or inter-mixed. Z. matrella with some variations frequently grouped separately but with some similarity with Z. tenuifolia, which was recently renamed as Z. pacifica. Hybrid types of zoysiagrasses were frequently found in Korea. New varieties such as 'Kunhee' and 'Green Ever' etc. were bred by ecotype selections, while 'Senock', 'Semil', 'Millock' were bred through pollination. Molecular approaches were also used to introduce beneficial genes into zoysiagrasses with no practical outputs by legal regulations. Currently popular varieties are inter-specific hybrid types such as 'Anyang' and other local zoysiagrasses as well as common zoysiagrass (Zoysia japonica) Production area in Korea was estimated as 2,947 ha with increasing problems of mixed or contaminated species and varieties.