• Korean Journal of Weed Science
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• v.14 no.4
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• pp.272-279
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• 1994

In order to compare the biological properties of benfuresate and cinosulfuron as herbicides for the chemical control of Eleocharis kuroguwai, some experiments were conducted at greenhouse and field conditions in 1993. Benfuresate and cinosufuron moved to 2cm and 6cm deep in paddy soil and inhibited the growth of E. kuroguwai. Benfuresate was absorbed into the roots of E. kuroguwai. whereas cinosulfuron was absorbed into not only the roots and shoots but also the mesocotyls. After the emergence was inhibited by the soil application of herbicides, the percentage of regrowing numbers was higher at cinosulfuron than at benfuresate, whereas the growth rate was higher at benfuresate on the contrary. Benfuresate brought about complete death of buds as a killing type, but cinosulfuron produced lots of abnormal shoots as an inhibiting type. Benfuresate was able to apply on soil surface from the preemergence to the early stage of 2cm high, but cinosulfuron was able to use from the preemergence to the stage of 15cm high. The foliar application of cinosulfuron showed a good control effect, but it induced a severe phytotoxicity to rice. A good control effect of Benfuresate/bensulfuron GR lowered at the late stage, but that of cinosulfuron/mefenacet/dymron GR at the early stage maintained until the late stage of 65 days after transplanting.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.28-33
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• 1989

This study was examined for the effect of tuber size, bud and tuber removal, and tuber cutting on growth of Eleockaris kuroguwai Ohwi. Elongation of plumule and radicle, and the weights of tuber, rhizome and shoot were increased as tuber size is large. The weights of shoot and tuber reduced by bud planting without tuber at 15 days after budding, however number of tubers were increased compared with normal tuber. When cross-cutting tubers were seeded, the weights of shoot, rhizome and tuber were produced as 84%, 85%, 71%, respectively compared with normal tuber, and the number of tubers was not influenced. The weights of tuber, rhizome and shoot were lowed as the bud removal, and there were a great number of tubers at bud removal of 15 days after budding. Tuber of E. k, contained as nonfibrous 78.9gr, phosphorous 77mg, iron 16.8mg, niacin 1.3mg per 100gr edble portion. The positive correlations were observed between shoot weight and tuber weight, and number of tubers.

• Spatial Information Research
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• v.3 no.1
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• pp.47-53
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• 1995

The weed survey in lowland rice fields through Korea was conducted in 1992 to determine a change of the weed communities based on different regions, soil types, planting methods, and cultural practices. GIS was applied to identify a spatial analysis of predominant weed species in specific region. On behalf of vegetatine analysis such as absolute and relative density, absolute and relative frequency, importance value, and summed dominance ratio(SDR), there was highly dominant with a perennial weed species, Eleocharis kuroguwai Ohwi over whole country. However, in particular it was most predominant at southem area of Gyunggi province in Korea. Thus, rice farmers of this area have to introduce a specific comperhensive control strategy against this predominant weed species.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.233-238
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• 1994

The experiment on sprouting and emergence properties of Eleocharis kuroguwai was conducted at laboratory and greenhouse conditions in 1993. Most of tubers had the apical dominance of buds at sprouting and had the competitive relationship for mesocotyl elongation. When pyrazosulfuron was applied on soil surface, all of apical buds were killed, but the first and second lateral buds survived to 50% and 90%, respectively, and the third lateral buds were almost at presprouted state. The tubers at 10-15cm deep soil emerged 1 week late and 35% low in emergence rate compared with the tubers at 2-5cm deep. As the plants emerged from the deep soil, the mesocotyl and the roots were distributed at deep soil more or less. Among the tubers buried at 10cm and 15cm deep soil, 25% and 30% respectively were not emergerd due to the suspension of mesocotyl elongation. Although the roots and shoots were removed from the tubers at the stage of 20cm high, all of mother tubers emerged again even 2 weeks late.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.171-175
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• 1994

Physiological changes in Eleocharis kuroguwai Ohwi as affected by bensulfuron-methyl {Methyl 2-[[[[[(4, 6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino] sulfonyl]methyl]benzoate} was determined to relate the characteristics with regrowth behavior. There were no changes in relative growth rate(RGR) during the period of growth cessation after application of bensulfuron-methyl. RGR's of the growth ceseased plants caused at 39 and 51 g/ha began to increase in between 25 and 30 days after application (DAA) and between 30 and 35 DAA, respectively. In untreated plant tuber carbohydrate rapidly decreased right after emergence and almost consumed within 40 days. There was no carbohydrate consumption during the period of growth cessation in bensulfuron-methyl-applied plant, but the content started to rapidly decrease with regrowth. Tuber viability lasted for 30 days in untreated plant, while tubers were viable for 60 and 70 days after application of bensulfuron-methyl at 39 and 51 g/ha, respectively. During the period of growth cessation the plants kept minimum respiration and photosynthesis, but with regrowth respiration and photosynthesis were resumed and rapidly increased.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.23-28
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• 1983

To study ecological characteristics of Eleocharis kuroguwai occuring in Korea its propagules were collected from 6 locations from the northern part to the southern part of Korea (Chuncheon, Suweon, Iri, Jeonju, Gwangiu and Milyang) in 1981, cultured and replanted 3 times (May 20, June 5, June 20) in 1982. They flowered from August 5 to August 27 when they were planted on May 20, and from August 20 to August 27 when they were planted on Tune 20. Plant height, number of tillers and top fresh weight/$m^2$ were 50-90cm, 500-875, and 175-750g, respectively when they were planted on May 20, and 40-70cm, 250-625, 325-625g, respectively when they were planted on June 20. Number of tubers per plant were 0.98-1.98 when they were planted on May 20, and 1.81-2.87 when they were planted on June 20. Eleocharis kuroguwai from Chuncheon or Suweon was more open in plant type, shorter in plant height, narrower in diameter of pedicel and shorter in inflorescence than those from Iri, Jeonju or Gwangju. Each of the local collections may be regarded as different ecotype, based on the above differences in morphology and responses in growth and flowering to the planting dates. The results appear to imply that Eleocharis kuroguwai weeds occurring in various locations of Korea are different one another in competitive avility with rice crop.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.49-55
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• 1994

A study was conducted to determine the effect of depth of burial, soil temperature and/or moisture on tuber sprouting of E, kuroguwai. Tubers were evenly distributed in the upper 30cm of soil. Tuber weight increased as depth of tuber formed increased. No dormancy in newly formed tubers was found, whereas mature tubers were dormant. When new tubers were subjected both to continuous $5^{\circ}C$ and to gradual decreasing temperatures regimes ranged from 20 to $1^{\circ}C$ for 30 days, the tubers remained non-dormant. Viability of tubers was reduced when buried at 5cm depth in dry and moist soil conditions, but no reduction was obtained when buried at 25cm depth, regardless of soil moisture conditions employed. Percent sprouting of tubers buried at 25cm depth increased with increasing duration of burial in three soil moisture conditions studied, wherease in dry and moist conditions percent sprouting of tubers buried at 25cm depth increased by 60-day burial and thereafter decreased. In submerged condition, tuber sprouting was greater when buried at 5cm depth than when buried at 25cm depth, and increased as duration of burial increased at the both depths.

• Mycobiology
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• v.43 no.3
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• pp.231-238
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• 2015

A total of 4 aquatic plants, Eleocharis kuroguwai Ohwi, Hydrocharis dubia Backer, Salvinia natans All., and Zizania latifolia Turcz., were sampled from representative two wetlands of South Korea. A total of 38 endophytic fungal strains were isolated from aquatic plants native to the Daepyeong wetland, and 27 strains were isolated from the Jilnal wetland. The internal transcribed spacer regions of fungal isolates were sequenced and a phylogenetic analysis was performed. In addition, endophytic fungal diversity from each wetland and host plant species was deduced. A total of 25 fungal genera were purely isolated, and 16 fungal genera were isolated from each of the two wetlands. Commonly isolated genera from both wetlands were Aspergillus, Cladosporium, Clonostachys, Fusarium, Leptosphaeria, Penicillium, and Talaromyces. This study revealed that fungal diversity varied with environmental conditions and by host plant in representative two wetlands.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.41-46
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• 1982

Herbicidal effectivity on perennial paddy weeds such as Sagittaria pygmaea Miq. and Eleocharis kuroguwai Ohwi was evaluated. Herbicides used were butachlor [2-chloro-2, 6-dietyl-N(butoxymethyl)-acetanilide], benthiocarb [S-(4-chlorobenzy)-N, N-diethyl-thiocarbamate], molinate (S-ethyhexahyaro-l-Hazpine-carbothiate], SW-751, Chlormethoxynil (2.4-dichlorophenyl-3-methoxy-4-nitrophenyl-ether), CNP (2.4.6-trichlorophenyl-4-nitrophenylether),oxadiazon [2-tertbutyl-4-(2.4-dichloro-S-isopropoxyphenyl)-5-OXO-1.3.4-Oxadiazoline], dinuron [1-dimethyl-benthyl)-3-pheratrylurea], bentazon [3-isopropyl-IH-2.1.3-benzothiadiazine-(4)3H-one-2.2-dioxide], ACN (3-chloro-2-amino-l.4-naphthoquinone), MCPB [4-(2-methyl-4chlorophenoxy), butyric acid], 2.4-D (sodium 2.4-dichlorophenoxy acetic acid), MCP) sodium 2-methyl-4-chlorophenoxy acetic acid), SST-5, TH 63. Graszin D (Bentazon/2.4-D) and Graszin M (Bentazon/MCP) Herbicidal effectivity was divided into three types. Type I was the complete control both leaf and tuber, and SW-751 was belonged to this type. Type II was the partial control that exhibit complete control within certain period after herbicide application. After a certain period, however, the lateral bud have the germinability and grow normally, there after. Chloromethoxynil, CNP, ACN, and Oxadiazon were belonged to this group. Type III was no control at all. For E. kuroguwai, application of CNP, Chloromethoxnil, Oxadiazon and SW-751 gave good control in the early stage shile 2.4-D, MCP, bentazon and glaszin-D controlled well the intermediate stage application. Based on this results, E. kuroguwai can be controlled by herbicide application either in the early stage or in the intermediate stage.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.204-210
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• 2012

The physicochemical properties of tuber starch in water chestnut have been studied. Peak viscosity, hot paste viscosity and cooling peak viscosity were 5679, 3146 and 4262 RVU, respectively. In three transition parameters, onset temperature ($T_o$), peak temperature ($T_p$), and conclusion temperature ($T_c$) were 64.1, 68.5 and $72.3^{\circ}C$, respectively. Gelatinization enthalpy (${\Delta}H$ gel) was 4.48 J/g. A-type starch has a smaller proportion (11.4%) of short chains ($DP{\geq}12$) and a larger proportion (57.2%) of short chains ($13{\leq}DP{\geq}24$). The tuber starch of water chestnut displayed an A-type X-ray diffraction pattern showing a strong diffraction peak at $2{\Theta}$ values of $15.18^{\circ}$, $17.13^{\circ}$, and $23.1^{\circ}$, and a weak peak at $2{\Theta}$ values of $18.1^{\circ}$, $20.06^{\circ}$, and $26.69^{\circ}$. Their crystallinity was 28.6% and the mean starch granule size was 21.5 ${\mu}m$.