• Korean journal of applied entomology
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• v.60 no.3
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• pp.305-312
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• 2021

This study was carried out to investigate insect pests and their damage caused to commercial amaranth in Gangneung, Gangwon-do, Korea, during 2019-2020. A total of seven families and 18 species were identified including three species of aphids, twelve species of stink bugs, and four species of moths. Among them, five species caused significant economic damage due to a large number of occurrences; Aphis fabae, Nysius plebejus, Polymerus cognatus, Spoladea recurvalis and Spodoptera exigua. Aphids started to occur from the end of April, and showed the greatest incidence in early June. Three Nysius species occurred from mid-May and showed the maximum density in late August, and then its population decreased from the beginning of September. Two species of moth caterpillars began to occur from mid-August and damaged amaranth until mid-October. Comparing the yields between amaranth plants with and without a spray of pesticides for each pest, the yield loss of seed by aphids and stink bugs were 51.9% and 69.8%, respectively. Also, the reduction rates of leaf biomass by S. recurvalis and S. exigua were 72.5% and 36.5%, respectively.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.46-69
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• 1996

The studies were conducted to obtain the basic information of the effects of pollutants on plant species and to select the plant species showing specific responses to the pollutants. For these purposes, paraquat, ammonium, and cadmium as a source of oxidative stress, nitrogen toxicity, and heavy metal toxicity respectively were treated to the plant species. Among the tested plants, Lamiaceae, Brassicaceae, and Caryophyllaceae were tolerant to paraquat, whereas Poaceae and Asteraceae were sensitive. Especially Mosla dianthera of Lamiaceae, Hemistepta lyrata and Aster pilosus of Asteraceae, and Paspalum thunbergii of Poaceae showed higher tolerance than others. Paraquat resistance was related with life style, overwintering capacity, so perennial and biennial species showed higher tolerance than annual species. In response to ammonium, Poaceae showed higher resistance while Fabaceae and Caryophyllaceae showed sensitiveness. Weed species having tolerance to ammonium were Echinochloa crus-galli var. praticola, Panicum dichotomiflorum, Setaria glauca, Chenopodium album, and Solanum nigrum, while Mosla dianthera, Arenaria serpyllifolia and Perilla frutescens var. japonica showed sensitiveness. In the response of plant species to cadmium, Digitaria sanguinalis, Amaranthus lividus showed higher resistance, whereas Galinsoga parviflora, Plantago asiatica, Ambrosia trifida, and Paspalum thunbergii showed sensitiveness. The injured degree on germination stage by pollutants did not related with injured degree on matured stage. During germination, the root elongation was more sensitive than shoot elongation by pollutants, paraquat, ammonium, and cadmium.

• The Korean Journal of Ecology
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• v.4 no.3_4
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• pp.93-108
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• 1981

This investigation includes the sick soil phenomenon caused by the self-poisoning of Setaria italica, Sorghum nervosum, Zea mays and Miscanthus sinensis among Poaceae. It elucidates whether the poison is directly excreted from the root or the secondary product resulting from the decomposition in the soil; the effect of Miscantus sinensis on the germination and growth of other plants, and the effect of Zea mays grown between furrows to shade Angelica gigas on its growth. The results obtained are as follows; Supplied with the leakage water from the pots, in which the same plants as the test ones were grown, in anticipation of the poison to be directly excreted from their roots, Sataria itlaica and Zea mays exhibited the growth inhibition more than 30%, whereas Sorghum nervosum and Miscanthus sisnensis were not effected in growth at all. When cultivated in the soils mixed with the roots of the some plants as the test ones, in anticipation of the poison to be the secondary product resulting from the decomposition in soil, Setaria italica and Zea mays showd growth inhibition of more than 50%, which is greater than that of the case of the leakage water, and Miscanthus sinensis exhibited no inhibition either, whereas Sorghum nervosum in the 50% plot showed heavy growth inhibition of more than 80% to the case of the leakage water. The common or uncommon plants found easily in the group of Misscanthus scinenis were not affected by the extracts of the steam and leaves of Miscanthus sinensis in germination and growth. Supplied with the leakage water from the pots in which Miscanthus sinensis was grown, among Lespedeza crytobotrya, Oenothera odorata, Raphanus sativus val'. acarlthiformis, Zoysia japonica, Patrinia scabiosaefolia. which are easily found in the group of Miscanthus sinensis, only Patrinia scabiosaefolia was slightly inhibited in growth in the 100% plot, whereas the others did not show any inhibition at all. Mean while, Amaranthus patulus. Solanum nigrum, Capsella bursa-pastoris val'. triangularis, Alopecurus amurensis, Chenopodium album val'. centrorubrum, which could not be found in the group of Miscanthus sinensis, were all distinctly inhibited. In the experiment on the effect of Zea mays on the growth of Angelica gigas, its growth was severely inhibited by one-half to two thirds with the increased concentration in both the cases of growing in the mixture of the soil and the powdered root of Zea mays and being supplied with the leakage water from the pot in which Zea mays was grown.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.265-279
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• 1987

About 140 weed species belonging to 42 families occurring in summer were observed in Ulreung island. The Compositae was the most wildely occurring family covering 27 weed species, followed by 21 species in Graminae, 9 in Polygonaceae, 7 in Leguminosae, and 7 in Labiatae etc. In terms of the lands classified, about 60 species in 26 families were observed in the cultivated and the medical crops grown areas, respectively, and 116 species in 40 families occurred in the non-cultivated land like the vicinity of the cultivated area and 94 species in 34 families in the valley. No. of species and families were much greater in the non-cutivated land than those of the cultivated one. The most dominant weed species in both the cultivated and its vicinity in Ulreung island were Digitaria sanguinalis, followed by Portulaca oleracea, Polygonum hydropiper, Equisetum arvensis, Artemisia princeps, Commetina communis, Setaria viridis in order. Community analysis was done by the method of Toyohara in two cultivated lands such as the general crop land and the medical herb crop grown land, and two non-cultivated areas such as the vicinity of the cultivated land and valley. The cultivated land consisted of the communites of P. hydropiper and Cyperus amuricus, including Bidens tripartita in P. hydropiper community. The medical crop grown land composed of three major communities like P. hydropiper, Amaranthus mangostanus and Sonchus asper in which A. mangostanus and S. media were presented in the ecoton, indicating community being transiting. In the non-cultivated areas like the vicinity of crop land, the communities of Erigeron annuus, P. oleracea, and Oxalis corniculata were dominant, and Dystaenia takeshimana was included in the community of E. annuus and Stellan'a aquatica in P. oleracea community. In the valley, Ranunculus quelpaertensis community was existed in between the communities of Sonchus asper and Plantago asiatica.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.57-62
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• 1982

This study was conducted to evaluate the important weed occurring in orchard and to establish on effective control method using combination of non-selective foliar applied herbicide followed by soil treated herbicide. In terms of quantity, Calysregia hederacea, Artemisia princeps, Ixeris chinensis, Cephalonopios segetum, Capsella bursa-pastoris, Setaria viridis, Chenopodium album, Trifolium repens, Digitarta sanguinalis in order were observed to be the most important weeds in May, In July the most dominant weeds were D. sanguinalis, Setaria viridis, Amaranthus lividus, Portulaca oleracea, Polygonum hydropiper, Acalypha australis, Artemlsia prtnceps, Miscanthus sinensis in order, showing D. sanguinalis to be the dominant species. D. sanguinalis was one single dominant species till autumn, followed by A. lividus, P. oleracea, A. australis. Simpson's index, 0.159 obtained in May just before herbicide application increased to 0.253 in July and again decreased to 0.233 in Sept. in the oxyfluorfen treated plot, meaning that no specific weed species were dominant, while in the untreated plot, D. saguinalis was relatively single dominant species, showing Simpson's index, 0.540 and this trend was mainained till autumn. The most effective herbicide to control D. sanguinalis and other annuals was oxyfluorfen at 0.47kg a.i./ha. when applied at preemergence treatment, showing more than 80% control of them for 65 days. The results suggest that paraquat at 32/ha (prod.) as the foliar application followed by oxyfluorfen 0.47kg a.i./ha applied as the preemergence at one week after paraquat treatment can maintain the clean orchard more than 65 days, showing one of the promising and applicable control system in orchard.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.121-130
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• 1985

The phenolic compounds identified from rye and wheat residues seemed to be p-coumaric, p-hydroxybenzoic, vanillic, ferulic, salicylic and syringic acids. Total phenol content of rye and wheat straw determined at heading stage was 0.1803% and 0.1702%, respectively. Total phenol content in straw was higher than that of root at all growth stages. The germination and growth of plants, such as Oryza sativa, Echinochloa creugalli, Cyperus serotinus, Portulaca oleacea, Amaranthus retroflexus, Digitaria saguinalis, and C. album were inhibited by treatments of authentic phenolic compounds as the concentrations increased. However, at the early stage, the germination and shoot growth of P. distinctus were markedly stimulated by them, and then the further growth of shoot and root was markedly inhibited by the prolonged treatment of phenolic compounds. The aqueous extracts from rye and wheat straw completely inhibited the germination of A. retroflexus and C. album at a high concentrations. The content of starch and protein in bulbs of P. distinctus was lower in the p-hydroxybenzoic acid treated plot, at $10^{-2}M$, than the untreated control.

• Journal of Korean Home Economics Education Association
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• v.27 no.3
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• pp.19-34
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• 2015

Current study aimed to evaluate elementary school children's perception and eating attitude towards vegetables and analyze environmental factors influencing it. Survey was conducted among elementary school students and their parents in Gangwon district, 410 subjects each(Total 742, 391 students, 351 parents). The results are as follows. Both the children(64.3%) and the parents(84.9%) showed high concern over health. 46.6% of children and 52.4% of parents admitted unbalanced eating behavior, and commonly avoided foods were mostly vegetables such as mushroom, carrot, garlic, sweet pepper-green, welsh onion, kimchi, pumpkin, or beans. Unbalanced eating habit was significantly related to health consideration in choosing what to eat(p<0.01) and interest in health(p<0.05). 70.9% of children with unbalanced eating habit showed intention for correction, and those with high interest in health had stronger intention (p<0.01). Regarding children's perception of 20 kinds of vegetables frequently used in school lunch, swiss chard leaf beet, amaranthus magistratus, and curled mallow were rarely heard of or hardly eaten before. Korean chinese cabbage, radish(62.7%), cucumber(62.1%), perilla leaves(60.4%), lettuce(58.1%), and spinach(54.5%) were among the most frequently eaten. Survey result on children's preference for the vegetables shows lettuce, cucumber, Korean chinese cabbage, perilla leaves, spinach, and radish were highly preferred and stem of garlic, crown daisy, sweet pepper-green, pepper, and curled mallow were the least preferred. There was a significant positive correlation(p<0.01, p<0.001) between children's and their parent's preference for each vegetables, implying that children's preference towards vegetables is greatly influenced by their parent's choice. Children showed negative attitude towards vegetables with strong flavor and tended to avoid vegetables that they remember as not tasty. This suggest that strong flavor and negative prior experience is what determines children's attitude in vegetable consumption. Many children said they try to eat vegetables even if they haven't had it before, and this tendency was significantly correlated with the degree of interest in health(p<0.05) and the degree of consideration of health in choosing what to eat(p<0.001).

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.219-224
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• 2015

This study was conducted to evaluate the effect of herbicidin, new natural herbicidal substances, derived from soil actinomycetes Streptomyces scopuliridis. Several weed species were subjected to examine the germination inhibition and herbicidal activity at the concentration from 100 to 2,000 ppm. There was no selectivity in germination inhibition and herbicidal activity against crops. Germination of Echinochloa oryzoides, Digitaria ciliaris, Abutilon theophrasti and Amaranthus retroflexus was inhibited completely when 7.81 ppm of extract was treated in petri dish. Pre-emergence application of herbicidin in soil condition showed low inhibition against weeds. However, post application of herbicidin in green house resulted in the necrosis of weeds at the concentration of 2,000 ppm. A. retroflexus was sensitive to herbicidin at the low concentration of 62.5 ppm, whereas E. oryzoides was tolerant to lower concentration of herbicidin until it became withered at the concentration of 2,000 ppm. In conclusion, herbicidal substances derived from S. scopuliridis herbicidin, which is consisted with herbicidin A and B, have dominant effect on germination and growth inhibition. On the other hand, herbicidin was insufficient to control gramineous weeds. In future, it will be needed to develop the combination of herbicidin with other herbicide or compounds to control gramineous weeds as well.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.159-175
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• 2015

Surveys of weed species on upland fields were conducted in Korea to investigate the occurrence of weed flora from April to May 2014 for winter crop fields and from July to August 2014 for summer crop fields. From the nation-wide survey, 375 weed species in 50 families were identified and classified to 162 annuals, 78 biennials and 135 perennials. Based on the occurrence ratio, the most weed species belonged to Compositae (73 species). 44 and 25 weed species belonged to Poaceae and Polygonaceae, respectively, and these 183 weed species in the most five families accounted for 49% of total weed occurrence. While 287 weed species in 45 families occurred in the winter crop fields, 339 weed species in 47 families occurred in summer crop fields. The most dominant weed species in Korean upland fields were Digitaria ciliaris, followed by Portulaca oleracea, Acalypha australis, Chenopodium album, Rorippa palustris etc. 129 weed species in 25 families were considered as exotic weeds. Based on the importance analysis, the highest value was C. album followed by Amaranthus lividus, Conyza canadensis etc. This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in upland fields of Korea.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.9-17
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• 1990

Erwinia carotovora subsp. carotovora, Pseudomonas viridiflava and Pseudomonas marginalis pv. marginalis were tested for their pathogenicity to 35 kinds of domestic flowering plants. Among them, the following domestic flowering plants showed clear symptoms. 1. Erwinia carotovora subsp. carotovora : (Needle inoculation). Carnation(Dianthus catgophylius L.), madagascar periwinkle(Vinca rosea L.), flower gentle(Amaranthus tricolor L.), snapdragon(Antirrhinum majus L.), chrysanthemum(Chrysanthemum morifolium Ram.), mexiacan ageratum(Ageratum houstonianum Mill), china aster(Callistephus chinensis), youth and old age(Zinnia elegans Jacq.), common nasturtium(Tropaeorum majus L.), scarlet sage(Salvia splendens F.), dahlia(Dahia hybrida), pot marigold(Calendula officinalis L.), begonia treevine(Cissus dicolor Blume), cosmos(Cosmos bipinnatus Cav.), globe amaranth(Gomphrena globosa L.), black eyed susan(Thumbergia alata Bojer), common gypsophila(Gypsophila elegans Bieb.), ghent gladiolus(Gladiolus gandavensis Van.), indian shot(Canna orchiodes Bailey), iris(Iris nertschinskia Lodd), cyclamen primula(Dodecatheon meadia L.), scarlet kafir lily(Clivia miniata Regel.), flowering cabbage(Brassica oleracea L.). (Spray inoculation). Carnation, madagascar periwinkle, flower gentle, snapdragon, common nasturtium, ghent gladiolus, indian shot, cyclamen primula. 2. Pseudomonas viridiflava : (Needle inoculation). Carnation, madagascar periwinkle, snapdragon, chrysanthemum, cockscomb, mexican ageratum, china aster, common nasturtium, common petunia(Petunia hybrida Vilm), pot marigold, begonia treevine, cosmos, black eyed susan, common gypsophila, ghent gladiolus, indian shot, cyclamen primula, scarlet kafir-lily, flowering cabbage. (Spray inoculation). Common nasturtium, ghent gladiolus, indian shot, cyclamen primula. 3. Pseudomonas marginalis pv. marginalis : (Needle inoculation). Carnation, madagascar periwinkle, flower gentle, snapdragon, cockscomb, mexican ageratum, youth and old age, common nasturitium, common petunia, sweet william(Dianthus barbatus L.), pot marigold, begonia treevine, cosmos, common gypsophila, ghent gladiolus, indian shot, iris, cyclamen primula, scarlet kafir-Lily, flowering cabbage. (Spray inoculation). Common nasturtium, ghent gladiolus, indian shot, cyclamen primula.