• Korean Journal of Plant Resources
• /
• v.23 no.3
• /
• pp.242-247
• /
• 2010

This study was carried out to elucidate the effect of mulching materials on the growth of Chinese chive (Allium tuberusum Rottler) and weed control. Chinese chive was grown under five mulching materials, pine leaf, oak leaf, rice straw, rice hull and sawdust, at the Experimental Farm of Chungbuk National University from June 20, 2009 to September 30, 2009. Amaranthus mangostunus, Digitaria sanguinalis, Portuclaca. oleracea, Echinochioa crus-galli var. frumetacea and Setaria viridis were dominant weeds. Both pine and oak leaves were significantly effective mulching materials in terms of weed control indices in both nursery and field. Soil moisture contents were 1.2~3.7% higher in mulching, especially in oak leaf mulching. Mulching with pine leaf significantly increased plant height, sheath length, leaf length, bulb-, root- and leaf-weights and yield of Chinese chive, but there were no significant differences among the other mulching materials although better than those in non-mulching.

• Journal of Plant Biology
• /
• v.29 no.2
• /
• pp.129-133
• /
• 1986

Transections of the stem region close to the shoot apex show the occurrence of an outer, complete ring of procambium and an inner group of discrete procambial strands. From the outer ring, small, discrete vascular bundles and vascular cambium originate, while the inner group forms the discrete, medullary vascular bundles with intrafascicular cambium. Secondary thickening is essentially due to the activity of the cylinder or complete ring of vascular cambium that originates from the procambium. The medullary intrafascicular cambia also form some secondary tissues. The vascular cambium produces secondary xylem inwards and secondary phloem outwards as in the normal secondary thickening process. The distinctive feature, however, is perpetual discreteness of the medullary vascular bundles. No successive series of cambia or secondary vascular bundles are found.

• The Korean Journal of Mycology
• /
• v.48 no.3
• /
• pp.325-328
• /
• 2020

Damping-off symptoms were frequently observed on young plants of edible amaranth (Amaranthus mangostanus) grown in vinyl greenhouses by farmers located in Goyang and Yangpyeong in Korea during disease surveys carried out in 2019 and 2020. The incidence of the disease was 1-20%. A total of eight isolates of Rhizoctonia sp. were obtained from the stems of the diseased plants. All the isolates were identified as Rhizoctonia solani AG-4, based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on edible amaranth by artificial inoculation. All the tested isolates of R. solani AG-4 induced damping-off symptoms on the inoculated plants; these symptoms were similar to those observed on the vinyl greenhouse plants surveyed. This is the first report of R. solani AG-4 causing damping-off in edible amaranth.

• 한국약용작물학회:학술대회논문집
• /
• 2009.05a
• /
• pp.187-188
• /
• 2009

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.173-173
• /
• 2022

In this study, we investigated whether there is another amaranth GBSS isoform in an attempt to characterize the synthesis of amylose in the pericarp. We used I2/KI staining to analyze the temporal and spatial starch accumulation patterns during seed development. The spatiotemporal starch accumulation patterns in developing seeds were observed by staining with I2/KI. Starch granules were observed in the pericarp in the initial developmental stage (3 DAP). A few starch granules were detected in the perisperm in the early-late developmental stage (8 DAP), during which the pericarp starch contents rapidly decreased. Starch granules were distributed throughout the perisperm in the mid-late developmental stage (15 DAP). Similar results were reported for other cereal crops, including barley, rice, and sorghum. Starch granules in the pericarp are synthesized during the early seed developmental stages but are absent in mature seeds. We recently reported that starch deposits in the perisperm of developing amaranth seeds are detectable only after the initial developmental stage. Prior to this stage, the pericarp is the major site of starch deposition. A recent study suggested that GBSSII isoforms are responsible for amylose synthesis in pericarps.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.15 no.2
• /
• pp.85-101
• /
• 2013

In order to search for distribution characteristics on C4 plants at the paddy fields, uplands, orchard and roadside in South Korea, vascular plants were investigated. Flora investigation had been carried out from May 2002 to October 2006 at 241 plots. In the results of survey, the flora of these areas consist of 74 families, 231 genera and 352 species totally. The class frequencies were arranged by the order of Magnoliopsidae (255 species), Monocotyledoneae (89 species), Pteropsida (7 species) and Sphenopsida (1 species). The number of species in each investigated agricultural field types was 55 families with 203 species in paddy field, 49 families with 218 species in uplands, 44 families with 115 species in orchard and 48 families with 202 species in roadside respectiviely. Representative species compositions of these four agricultural field types were characterized by Artemisia princeps, Persicaria thunbergii in paddy field, Artemisia princeps, Erigeron annuus in upland and roadside, Commelina communis, Digitaria ciliaris in orchard, respectively. Therefore, indicative species in agricultural ecosystem was Artemisia princeps. Among the investigated 352 species, $C_4$ plants identified were 38 species, and the occurrence ratio of $C_4$ monocotyledonous plants were higher in paddy field, orchard and roadside than upland. Such differences in the occurrence ratio of $C_4$ plants under diverse agricultural field types reflect differences in environmental condition such as micro-climate, soil moisture under various agricultural fields. Dominant $C_4$ monocotyledonous plants were Digitaria ciliaris and Commelina communis, while $C_4$ dicotyledonous plants were Amaranthus mangostanus and Chenopodium album var. centrorubrum in agricultural fields. Naturalized plants were identified as 47 species and occurrence ratio were higher in upland and roadside than other agricultural field types. Among the investigated naturalized plants, $C_4$ plants were Amaranthus mangostanus and Amaranthus retroflexus. Distribution characteristics of representative $C_4$ plants in agricultural field types, revealed that the projected increase in temperature due to climate change may provide better conditions for the growth of $C_4$ plants. Thus, the necessity of long-term monitoring should be conducted on the diffusion of $C_4$ plants that may threaten influence agroecosystem in Korea.

• Korean Journal of Organic Agriculture
• /
• v.16 no.1
• /
• pp.127-142
• /
• 2008

This study was carried out to germination characteristics by temperature conditions and allelopathic effects of aqueous extracts on Amaranthus spinosus L. in order to investigate the competitive dominant in plant ecosystem and possibility application of natural herbicide. A. spinosus L. sprouted after 24 hour from seeding in $30{\sim}45^{\circ}C$ treatment. The germination ratio of A. spinosus L. was the highest estimated at 63.3(${\pm}2.9$)% in $40^{\circ}C$ treatment, followed by 33.3(${\pm}2.9$)% in $35^{\circ}C$, 1.7(${\pm}2.9$)% in $30^{\circ}C$ and 5.0(${\pm}0.0$)% in $45^{\circ}C$ treatment. It was generally decreased the Relative Germination Ratio(RGR), the Relative Elongation Ratio(RER), the Relative Fresh weight Ratio(RFR) of receptor plants by the aqueous extracts of concentration of A. spinosus L. but it was differently inhibited the kind of receptor plant species. And it was different effected among growing regions that aqueous extracts of concentration of A. spinosus L. inhibited more root than shoot. The total phenolic compounds content of A. spinosus L. was decreased gradually middle, first and last of growth stage, and gradually decreased to leaves, roots and stems. We think that A. spinosus L. appeared high germination ratio at a short period and showed allelopathic effects on other plants. Therefore A. spinosus. L. hold the competitive dominant of plant ecosystem in Jeju Island and possibility application of natural herbicide.

• Korean Journal of Organic Agriculture
• /
• v.22 no.2
• /
• pp.303-319
• /
• 2014

The study researched germination of the plants and growth of experimented bacteria according to concentration of water extract in order to provide basic data for developing natural agricultural resources by using naturalized plants including Solidago altissima, Amaranthus retroflexus and Sida spinosa. As concentration of water extract increased, most of test plants showed a decrease in relative germinability. Sida spinosa(r=-0.540, p<0.01), Physalis wrightii(r=-0.693, p<0.01), Amaranthus retroflexu(r=-0.724, p<0.01), Solidago altissima(r=-0.728, p<0.01) and Eclipta prostrata(r=-0.779, p<0.01) showed tendency of decrease in relative germinative power in order, respectively. For average germination period, as concentration of the processed group increased, the time for germination increased (r = 0.769, p<0.01) and according to donor plants and test plants, there was a little difference. Also, as concentration of water extract of donor plant, length of above-aerial part(r=-0.587, p<0.01), length of underground part(r=-0.741, p<0.01), fresh weight(r=-0.574, p<0.01) and generation of root hair decreased. An then, for growth of test fungi according to concentration of water extract of donor plants, growths of Botrytis cinerea(r=-0.266, p<0.05), Diaporthe citri(r=-0.323 p<0.01), Colletotrichum gloeosporioides(r=-0.512, p<0.01), Pythiumultimum(r=-0.581, p<0.01) and Rhizoctonia solani(r=-0.806, p<0.01) were repressed in order, respectively. For total amount of content of phenol with herbicidal and Antifungal activities, S. altissima $17.3{\pm}0.5mg/g$, A. retroflexus $13.1{\pm}0.3mg/g$, P. wrightii $12.0{\pm}0.4mg/g$, S. spinosa $9.5{\pm}0.1mg/g$ and E. prostrata L. $4.1{\pm}0.1mg/g$ showed in order, respectively. As these results are summarized, donor plants which were naturalized, have competitive advantage because they release phenolic compounds with allelopathic effect and affect on germination, growth and fungi growth on underground flora compared to native plants and they have eligibility for natural herbicide and germicide.

• Weed & Turfgrass Science
• /
• v.3 no.4
• /
• pp.284-291
• /
• 2014

We surveyed the distribution of exotic weeds in the 350 upland crop fields of Gyeonggi-do. The exotic weeds were summarized as 78 taxa including 19 families, 52 genera, 74 species and 4 varieties. Among the total exotic weeds, the summer annuals were 48.7%, the winter annuals 28.2%, and the perennials 23.1%. Compositae was dominant family (32%), followed by Gramineae (8%), Polygonaceae (8%) and Malvaceae (7%). Dominant exotic weeds in northern Gyeonggi-do were Amaranthus lividus, Ambrosia trifida, Chenopodium album, Bidens frondosa and Erigeron Canadensis, and in southern Gyeonggi-do were Chenopodium album, Erigeron Canadensis, Erigeron annuus, Taraxacum officinale and Galinsoga ciliate. The most dominant exotic weeds in the Gyeonggi-do were Chenopodium album, followed by Amaranthus blitum, Erigeron canadensis. Canonical correspondence analysis for investigation of correlation between exotic weeds occurred in northern and southern Gyeonggi-do showed that the exotic weeds in northern Gyeonggi-do were more diverse then in southern Gyeonggi-do. This information could be useful for establishment of exotic weed control methods in Gyeonggi-do.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.28 no.4
• /
• pp.307-314
• /
• 2008

No comprehensive tillage system of corn (Zea mays L.) has been conducted in Korea. Therefore, this experiment was carried to determine soil characteristics, weed and forage production in tillage system of corn. Plot was allotted to one of four treatments in a randomized block design using tillage system. The four treatments were (T1) conventional tillage, plow and rotary till, (T2) rotary till, (T3) disk till, and (T4) no-till system. In soil characteristics before planting and after harvest of corn, pH and organic matter at planting date was higher than at harvest date, however, there were no difference among tillage system. Days from planting to silking of no-till was the longest among tillage system. Lodging resistance of disk and no-till were higher than conventional and rotary till due to its thicken stem diameter. Main weed in corn field are barnyard grass (Echinochloa crusgall), velvetleaf(Abutilon avicennae), crabgrass (Digitatia saguinalis), and redroot pigweed (Amaranthus retroflexus). Weed population was lower in no-till than others tillage system. Dry matter (DM) content and ear percentage of conventional and rotary till were higher than others in corn field. However, DM and total digestible nutrients (TDN) yields of disk and no-till were higher than those of conventional and rotary till. Therefore, disk and no-till are more suitable in corn silage system because of high lodging resistance and forage yield, and low weed population.