• Weed & Turfgrass Science
• /
• v.3 no.4
• /
• pp.292-298
• /
• 2014

Purple ammannia (Ammannia coccinea Rottb.) is an exotic weed originated from North America. It was known to be a noxious weed in a rice paddy field for the competition with rice. We investigated its distribution and habitat types in Korea to obtain basic data for the management plan of this species. Although purple ammannia is currently not a dominant species in natural habitats, its nationwide distribution was found in our study. We categorized the types of its habitats as margins of rice paddies, abandoned paddy fields, riverine wetlands and reservoirs. Particularly, purple ammannia plants were frequently located along banks of irrigation channels that ran through rice paddies and surrounding wetlands. Because they mainly occurred along the direction of water flow, we considered that the plants have spread along water courses. A total of 69 vascular plant taxa was identified at the habitats of purple ammannia. The largest group of life form among purple ammannia population was therophytes, which indicates that purple ammannia mostly grow in the disturbed habitats.

• Korean Journal of Weed Science
• /
• v.17 no.2
• /
• pp.163-168
• /
• 1997

The experiment was conducted in 1996 to investigate distribution, germination characteristics, and effective control of Abutilon theophrasti in corn fields. The regional distribution of A. theophrasti showed that it was higher in Gyenggi province than in Kangwon, Chungnam, or Chonllanambug provinces because of many dairy farms located in Gyenggi province where fresh corn was used as ensilage. The optimal temperature of the weed seed germination was around 15~$20^{\circ}C$ and germination rate was 73~93% in 1~5cm of burial depth. The weed was able to be controlled effectively when treated 10 days after seeding more than just after seeding with herbicides, pendimethalin 31.7% EC, linuron 50% WP and pendimethalin linuron 25% EC with an acceptable phytotoxicity.

• Weed & Turfgrass Science
• /
• v.7 no.2
• /
• pp.111-119
• /
• 2018

This study was carried out to investigate the differences in germination and growth of Quamoclit coccinea Moench under various temperatures, seeding depths, and levels of shading and soil moisture for effective weed management. Seed dormancy of Q. coccinea Moench was over 1 year; best results were obtained when seeds were soaked in sulfuric acid for 15 minutes in order to break the dormancy. Germination rates of Q. coccinea Moench ranged from 69 to 73% at $25-35^{\circ}C$ and 26% at $15^{\circ}C$. The germination rates ranged from 70-84% at 2, 3, 5, 7, and 8 cm of seeding depths. In addition, the germination rates were 7% and 13% at 12 cm and 15 cm of seeding depths, respectively, and showed normal growth at the both seeding depths. Q. coccinea Moench showed a high germination rate regardless of shading levels, but shoot fresh weight varied depending on the level of shading as follows: 20%>no shading=shading 35%>shading 50%>shading 75%=shading 90%. Q. coccinea Moench did not germinate when soil had a saturation rate of either 30% or 100%. However, 60-83% of seeds germinated with optimal growth when soil had saturation rates of 60% and 80%.

• Korean Journal of Weed Science
• /
• v.1 no.1
• /
• pp.78-83
• /
• 1981

This study was attempted to determine the major weed species occurring in Korean turfgrass, Zoysia japonica Steud. and to evaluate the most effective means for controlling them. More or less 40 weed species were determined to occur in Korean turfgrass. In terms of quantity and frequency of occurrence, Trifolium repens L., Digitaria sanguinalis (L.) Scop., Draba nemorosa var. hebecarpa Lindbl, Erigeron canadensis L., and Cyperus amuricus Max were observed to be the major weeds. Simpson's index, 0.306 was obtained to be the major weeds. Simpson's index, 0.306 was obtained in the golf course, Jinryang, Gyungsan-gun, meaning that no specific weed species were dominant, but in Kyungpook National University campus, Trifolium repense L. was a single dominant species, indicating Simpson's index, 0.776. The most effective herbicides to control Trifolium repense L. and other broad leaf weeds were MCPP [2-(2-methyl-4-chlorophenoxy) propionic acid), followed by 2,4-D (2,4-dichlolophenoxy acetic acid). Increased rates of both herbicides increased markedly their effectivity against weeds, with very slight injury against turfgrass. MCPP at 2.8 kg(a.i.)/ha gave excellent control without any injury and 2,4-D at 1.0 kg(a.i.)/ha.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.485-489
• /
• 2005

Fallow paddy has been increased in disadvantageous farming condition area because of importation of foreign agricultural products, labor cost and the imbalance between farming cost and agricultural products price since 1990. The fallow paddy that has gradually increased needs to be prevented from the devastation by weed breeding for re-cultivation. In this study, two fallow paddies that manage with different water depth from the experimental field were selected for observation, and analysis of water quality, water balance and plant body change. The managed fallow paddy was more effective in water quality purification and plants growth control than non-managed fallow paddy. And the fallow paddy managed with a some degree water depth was the most effective field on weed control.

• Journal of Ginseng Research
• /
• v.23 no.3 s.55
• /
• pp.135-147
• /
• 1999

Nine herbicide products (fluazifop-p-butyl, clethodim, MCPA-sodium, 2,4-0 amine, chlorthal dimethyl, diquat, glyphosate, ethalfluralin and oryzalin) were evaluated for use on ginseng (Panax quinquefolius). Products varied in their ability to suppress weeds and certain materials were phytotoxic to ginseng in some trials. Chlorthal dimethyl (broadleaf weeds), MCPA-sodium (broadleaf weeds), fluazifop-p-butyl (grass weeds), and clethodim (grass weeds) were found to be effective as weed control agents and did not adversely affect ginseng growth. Other products tested were either not efficacious or were phytotoxic to ginseng in some trials. Weed populations were mainly introduced into the planting sites via the straw mulches used in ginseng cultivation.

• Weed & Turfgrass Science
• /
• v.3 no.4
• /
• pp.354-361
• /
• 2014

This study was conducted to investigate whether several composted liquid manures (CLMs) are useful for biological control of large patch on zoysiagrass and investigate the chemical and biological factors to suppress large patch in soil treated with CLMs. The CLMs were produced at 4 different facilities for livestock excretion treatments located in Korea. Field experiments were carried out at 5 golf courses located near each facility. CLM and Chemical fertilizer (CF: water soluble fertilizer, 20-20-20) were applied four and three times with N at $12g\;m^{-2}$ per year, respectively. There was significant increase of concentration of K, Na, and Cu of soil treated with CLM compared to CF treatment. Among experimental plots, CN and GG2 plot sites were shown significant higher effect of biological control 80% and 50% respectively against large patch disease. The number of bacteria, Actinomycetes, and fungi in soil at these sites significantly increased and fluorescein diacetate hydrolytic activity was enhanced, while the soil was treated with CLM. The results of this study demonstrated that CLM application has effect on soil to suppress large patch and reduce the use of fungicide in environment-friendly turf management.

• Weed & Turfgrass Science
• /
• v.3 no.2
• /
• pp.130-136
• /
• 2014

Tall fescue is commonly well-adapted for low maintain area because of its wear resistance, deep root system, and drought tolerances. Deep and infrequent irrigation refers to applying large amounts of irrigation, 1.3 to 2.5 cm or more, in a single irrigation event. Light and frequent irrigation is commonly used with small amounts of water, 0.3 to 0.6 cm, every day or every other day. N use for turfgrass management is often unnoticed for water management. The objective of this field study was to evaluate the effects of irrigation frequency and N rates for tall fescue growth. The three irrigation treatments were no irrigation (precipitation only), 0.5 cm applied every other day, and 1.8 cm applied once a week at one irrigation event. The nitrogen (N) treatments were the low, medium, and high N rate treatments. The low, medium, and high N treatments were applied over 2, 4, and 6 applications, respectively. If high main maintenance of tall fescue is not important and water source is limited, irrigation is not necessary and, the $9.8gNm^{-2}yr^{-1}$ of two applications can be recommended for tall fescue under the weather condition of the study.

• Korean Journal of Agricultural Science
• /
• v.42 no.2
• /
• pp.87-92
• /
• 2015

This study was conducted to evaluate the herbicidal efficacy of carfentrazone-ethyl mixtures in direct-seeding flooded rice. The efficacy of three different carfentrazone-ethly mixtures was greater than pyrazosulfuron-ethyl pyriminobac-methyl GR (PP GR). Weeding efficacy of three different carfentrazone-ethly mixtures was more than 96.9%. No phytotoxic effect was observed in the rice based on the plant height and the number of tillers. Yield of rice un three different carfentrazone-ethly mixtures application was more than both in the PP GR and in the hand weeding. Based on these data, three different carfentrazone-ethly mixtures can be applied to provide an effective weed management in direct-seeding flooded rice.

• Proceedings of the Korean Society for Information Management Conference
• /
• 2000.08a
• /
• pp.129-132
• /
• 2000

GIS(Geographic Information System) tool has been applied to determine a spatial difference of weed population density in paddy field and it has introduced to rice yield difference among counties as well as to rice blast in Korea. There was highly difference between sampling sites in terms of spatial analysis which may imply to be able to apply this tool for the precesion agriculture in the 21 century.