In 2022, the Korean Ministry of Environment designated Parthenium hysterophorus as an ecosystem-disturbing plant. The purpose of this study was to present a management plan for P. hysterophorus considering its distribution, morphological, physiological, and ecological characteristics, and to introduce various control techniques. P. hysterophorus is native to Central America and occurs in about 45 countries worldwide. However, in Korea, it only grows in some areas of Tongyeong and Changwon, Gyeongsangnam Province. P. hysterophorus is an annual plant and spreads by seeds, moves between countries in the process of importing and/or exporting agricultural seeds, and spreads by agricultural machinery and vehicles after introduction. P. hysterophorus releases parthenin, an allelochemical that suppresses the occurrence of the surrounding vegetation, from its stems and roots. In addition, P. hysterophorus causes damage to humans and livestock through various allergens. P. hysterophorus can be controlled by physical methods, such as cutting its stems or pulling roots, and by treatment with non-selective herbicides, such as glyphosate. Many biological control research studies have been conducted and, unfortunately, there is no a practical solution so far.

본 연구는 allelopathic potential을 지닌 벼의 교잡종을 포장에서 재배하여 그 식물체의 잎을 생물검정에 이용하여 allelopathy 효과 유무를 검정하고, 생물검정으로 선발된 교잡종을 대상으로 phenolic compounds를 조사하여 allelochemical로써의 가능성을 확인하고 나아가 phenolic compounds 생합성에 관여하는 효소의 활성 측정과 이 효소의 작용에 의해 유도되는 phenolic compounds를 구명한 결과는 다음과 같다. 1. 포장상태에서 피를 대상으로 생물검정을 실시한 결과 양친으로는 Kouketsumochi, Woo co chin yu에서 공통적으로 90% 이상의 높은 피뿌리 생장 억제율을 보였고, 교잡종에서는 Kouketsumochi/Woo co chin yu, Dongjinbyeo/Kouketsumochi, Dongjinbyeo/Woo co chin yu 조합에서 80% 이상의 높은 억제율을 나타냈다. 2. Kouketsumochi의 PAL 활성은 protein 1kg당 로 타 공시품종보다 높았다. 또한 Kouketsumochi와의 교잡종도 타교잡종보다 높은 것으로 나타났다. 3. Kouketsumochi의 cinnamate 함량은 생체중 1g당 으로서 다른품종이나 교잡종보다 2~5배 높았고, Kouketsumochi와의 교잡종도 타교잡종보다 높았다.

1. 꽃무릇으로부터 용매를 다르게 하여 잎과 인경의 MeOH와 수용추출물을 bioassay 한 결과, 농도가 5% 및 10%로 증가하였을 때는 전혀 발아되지 않았으며, 1%에서는 근장이 크게 억제되었다. 용매간의 추출효과에는 차이가 없었으나, 상추의 생장에서는 인경추출액이 잎추출액보다 억제효과가 다소 높은 것으로 보였다. 2. 꽃무릇의 인경을 추출하여 UV를 조사하였을 때 Rf 0.49-0.52에서 보인 spot는 GC-MS에 의해 lycoris alkaloid계통의 lycorenan으로 동정되었다.

마편초과의 좀목형 엽에 함유된 물질의 allelopathy 효과를 구명하기 위해 수용성 엽 추출액, 메탄올 엽 추출액, 엽 분말과 토양과의 혼화된 pot에 각각 상치, 이탈이란라이그라스, 개솔새, 억새 종자를 발아실험하여 발아억제물질을 분석한 결과는다음과 같다. 1. 좀목형 엽 분말을 증류수에 각각 24, 48, 72 시간 침지 후 추출물에 상치, 이탈리안라이그라스, 개솔개, 억새 종자를 파종한 후의 발아율은 각 처리구마다 대조구마다 높은 발아억제를 보였고, 48시간 침지시에는 각각 26.9%, 58.8%, 6.6%, 22.2%의 발아율을 보여 강한 발아억제현상르 보였다. 2. 좀목형 엽 분말을 메탄올 75%에 24, 48시간 침지 후 추출물에 이탈리아라이그사스, 개솔새, 억새 종자를 파종한 후의 발아율은 48시간 추출액때 각각 33.3%, 15.4%, 7.7%를 보여 48시간 수용성 추출액과 24시간 메탄올 추출액보다 강한 발아억제효과가 있었다. 3. 좀목형 엽 분말과 Vermiculite를 1: 99.5: 95, 10:90, 20:80(w/w)으로 구분한 pot에 공시수종을 파종한 결과 엽 분말의 비율이 높을수록 발아억제효과가 컸으며, 엽 분말이 20%인 경우 발아된 부분의 건중량의 비율은 실험구와 대조구간에 비교한 발아율의 비율보다 훨씬 낮아 생장억제효과가 있는 것으로 나타났다. 4. Column chromatography의 TLC를 이용하여 최종 7 fraction을 찾고 생물검정 결과, 5, 6번 fraction에 강한 활성을 나타냈다. 5. UV 와 IR분광분석 결과 UV 분광분석은 256 nm과 336nm에서 흡수 최대를 나타내었으며, 이들은 시르시트시약을 사용하여 검토한 결과 7위에 에테르 결합한 전형적인 플라본류로 추정되었고, IR 분광분석 결과 지방족에 에테르결합이 존재하는 것으로 생각되었다. 6. Py-GC-MS 분석으로부터 5, 6 fraction의 경우 플라본류에 1개의 당이 결합한 배당체 구조이고 B환의 경우 1개 또는 2개 이상의 페놀성 수산기의 존재가 예상되었다.

Rumex속 식물의 경쟁적 우세원인을 규명하고 친환경 제초제 등의 자원화 연구에 기초자료로 제공하고자 이 식물의 생육특성과 Allelopathy효과를 알아보았다. 돌소리쟁이 수용성추출액을 이용하여 벤트그라스 (Agrostis stolonifera subsp. stlolnifera), 배추(Brassica campestris subsp. napus var. pekinensis), 이탈리안라이그라 스, 토끼풀(Trifolium repens), 가시비름(Amarathus spinosus), 들묵새(Festuca myuros)등의 상대 발아율을 조사하 여 수용성 추출액이 농도가 높아질수록 발아가 억제되는 경향을 볼 수 있었다. 특히 제주도 위해식물인 가시 비름이 수용성추출액 50% 이상에서는 발아가 되지 않는 경향을 보여 선택적으로 가시비름에 많은 억제력을 보이는 것으로 연구되었다. 애기수영의 수용성 추출액을 이용하여 벤트그라스(Agrostis stolonifera subsp. stlolnifera), 도깨비바늘(Bidens bipinnata), 배추(Brassica campestris subsp. napus var. pekinensis), 크림슨클로버 (Trifolium incarnatum), 이탈리안라이그라스, 토끼풀(Trifolium repens), 등의 발아율을 조사하였는데 수용성 추 출액의 농도가 높아질수록 발아가 억제되는 경향을 보였으며, 배추의 경우 100% 수용성 추출액의 농도에서는 발아가 되지 않아 배추의 생장에 억제력이 높게 나타났다. 반면 평균발아일수는 증가하는 것으로 나타났다. Rumex속의 식물의 수용성추출액을 실험하므로써 식물의 선택적 생장억제력을 알수있었으며 이 실험자료를 토대로 친환경농가에서 대상 식물의 방제에 직접 사용해 볼 수 있고, 추후 친환경자재 개발의 기초자료 될 것으로 기대된다.

A series of methanol extracts from leaf and root parts in spring- and winter-barley plants were assayed to determine their allelopathy and antioxidant activity. The methanol extracts applied on filter paper in a Petri-dish significantly inhibited root growth of Chinese milkvetch (Astragalus sinicus L.) seedlings. Leaf extracts at 25 and 50 g L-1 inhibited root growth of Chinese milkvetch seedlings more than root extracts. No difference in phytotoxic effects of spring- and winter-barley seedlings extracts on root growth of Chinese milkvetch was observed. Methanol extracts dose-dependently increased DPPH free radical scavenging activity in vitro. DPPH free radical scavenging activity was higher in the methanol extracts from winter-barley seedlings than in those from spring-barley seedlings, and from leaf extracts than from root extracts. The antioxidant potential of the individual fraction from the methanol extracts of spring-barley seedlings was in order of n-butanol>ethyl acetate>water>chloroform>n-hexane fraction. By means of HPLC analysis, spring-barley (200.62 mg 100g-1 ) had more amount of total phenol acid than winter-barley (114.08 mg 100g-1 ). Especially, ferulic acid was detected in spring-barley extract (183.46 mg 100g-1 ) as the greatest amount. These results suggest that early seedlings of barley plants had potent allelopathy and antioxidant activity, and their activities were differently exhibited depending on plant parts and growing condition.

Common thistle contains water-soluble substances that are phytotoxic to neighboring plant species. A series of aqueous extracts from leaves, stems, roots and flowers of common thistle (Cirsium pendulum Fisch.) were assayed against alfalfa (Medicago sativa) seedlings to determine their allelopathy, and the results showed highest inhibition in the extracts from flowers and leaves, and followed by stems, and roots. The extracts at 40 g dry tissue L-1(g~;L-1) applied on filter paper in a Petri-dish significantly inhibited root growth of test plant by 87%. Methanol extracts at 100 g L-1 from leaves inhibited root growth of alfalfa and barnyardgrass (Echinochloa crus-galli) by 89 and 98%, respectively. Hexane and ethylacetate fractions of common thistle reduced alfalfa root growth more than did butanol and water fractions. Incorporation into soil with the leaf residues at 100g~;kg-1 inhibited shoot fresh weights of barnyardgrass and eclipta (Eclipta prostrate) by 88 and 58%, respectively, showing higher sensitivity in grass species. These results suggest that common thistle plants had allelopathic potential for eco-friendly vegetation management, and that especially their activities were differently exhibited depending on plant part.

Compositae plants are known to contain biologically active substances that are allelopathic to agricultural crops as well as weed species. Aqueous or methanol extracts and plant residues from leaves of Xanthium occidentale were assayed against alfalfa (Medicago sativa) to determine its allelopathic effects, and the results showed that the extracts applied onto filter paper significantly inhibited seed germination as well as root growth of alfalfa. Aqueous leaf extracts of 40g L-1 were completely inhibitory on root growth of alfalfa, while root growths of barley (Hordeum vulgare L.) and soybean (Glycine max L.) were less sensitive. Leaf residue incorporation at 100g kg-1 into soil on seedling growth of barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) inhibited both shoot and root fresh weights of barnyard grass by 94 and 96%, respectively. Methanol extracts from BuOn and EtOAc fractions of X. occidentale reduced alfalfa root growth more than did those from hexane and water fractions. The results based on bioassay of extracts and residues show that X. occidentale had potent an allelopathic activity against other plant species.

Rice and weed interference in the paddy field caused by resource competition and allelopathy. Evaluation method of active weed suppressive behavior of rice to weed was developed by eliminating light competition at soil condition. Twenty eight days old rice seedlings (6-7 leaf stage) which was grown at saturated, no drainage pot were clipped above 3~~4cm from the soil surface. Weeds seeded around clipped rice stem, named ratoon seeding screening method, showed varietal suppressive difference to Echinochloa crus-galli, Echinochloa crusgalli var. praticola and Monochoria vaginalis. Potential allelopathic rice varieties, Sathi, AC1423 and PI312777 showed better suppressive activity to weed seedling growth than Nonganbyeo and Keumobyeo. Weed suppression of one plant of rice cultivars could be evaluated by the cell size of 2.5~times2.5cm at rice clipping of seedling 29 days after rice seeding.

Alfalfa (Medicago sativa L.) plants have been reported to be autotoxic as well as allelopathic. Laboratory and greenhouse experiments through petri-dish and pot test were conducted to determine autotoxic effects of alfalfa leaf and soil extracts on the germination or early seedling growth of alfalfa, and to evaluate allelopathic effects of alfalfa leaf residues on alfalfa, barnyard grass, com, eclipta and soybean. Alfalfa seed germination was delayed depending on aqueous extract concentration, with no difference in final germination after 48 hours. Alfalfa root length was more sensitive to the autotoxic chemicals from leaf extracts than was germination or shoot length. Root growth of alfalfa was significantly inhibited at extract concentration of more than 1 g dry tissue/L (g ~textrmL-1 ). Hypocotyl growth, however, was not affected by all the concentrations of leaf extracts. Soil extracts from 4-yr-old alfalfa stand significantly reduced alfalfa root length by 66%, while soil extracts from 0,1, and 3yr-old stand stimulated root length up to 14-32% over the control. Residue incorporation with dry matters of alfalfa leaf at 100 g ~textrmkg-1 reduced seedling length of several crop and weed species, ranging from 53 to 87% inhibition. Addition of nutrient solution into alfalfa leaf extracts alleviated alfalfa autotoxic effect. This result indicates alfalfa leaf and soil extracts or residues could exert autotoxic as well as allelopathic substances into soil environments during and after establishment.

Greenhouse and laboratory studies were conducted to determine the allelopathic potentials of extracts or residues from sweet potato (Ipomoea batatas L. (Lam). The extracts applied on filter paper in a Petri dish bioassay significantly inhibited root growth of alfalfa. Aqueous leachates at 40g dry tissue ~textrmL-1 (g ~textrmL-1 ) from leaves showed the highest inhibition against alfalfa, and followed by stems and roots. Alfalfa root growth was significantly inhibited by methanol extracts of the same plants as the concentration increased. The effect of residue incorporation into soil on seedling growth of com, soybean, barnyard grass and eclipta was examined in the greenhouse, and results showed that the leaf residues at 200g ~textrmkg-1 by plant parts inhibited shoot dry and root dry weights of test plants by 60-80%. By means of HPLC, causative allelopathic substances present in plant parts of sweet potato "Sinyulmi" were identified as coumarin, trans-cinnamic acid, o-coumaric acid, p-coumaric acid, and chlorogenic acid. Total content of these compounds for leaves extracts were detected as the greatest amount in EtOAc fraction, especially trans-cinnamic acid was the greatest component. These results suggest that sweet potato plants have herbicidal potentials, and that their activities exhibit differently depending on plant parts.ant parts.

본 실험은 알파파 꽃 추출물로부터 Allelopathy와 Autotoxicity에 관련되는 활성물질을 분리, 동정하기 위하여 실시하였다. 알팔파 꽃 200g을 80% MeOH로 추출하여 CHCl3 층을 silica gel thin layer chromatography (TLC), microcrystalline cellulose thin layer chromatography (MCTLC)와 droplet countercurrent chromatography(DCCC)의 분획을 이용하여 생물검정을 행하고 DCCC의 생물검정에서 가장 억제력을 보였던 분획 5와 6은 HPLC로 활성물질을 동정하였다. HPLC분석 결과 분획 5에서는 ferulic acid, caffeic acid, vanillic acid, rutin, narringin 이, 분획 6에서는 ferulic acid, caffeic acid, vanillic acid, rutin, coumarin이 동정되었다. 이들 동정된 물질을 이용한 알팔파와 돌피에 대한 발아실험에서도 모두 알팔파와 돌피의 발아와 생육에 억제적으로 작용하였으며, 이중 coumarin의 처리가 가장 억제적이었다. 따라서 이들 물질이 알팔파와 돌피의 autotoxicity와 allelopathy에 관련하는 것으로 생각되었다.

미국자리공 및 겨자무의 잎추출물을 이용하여 기내배지상에서 몇가지 작물들과의 allelopathy를 조사한 결과는 다음과 같다. 1. 미국자리공 잎의 methanol 추출물의 농도가 증가함에 따라 공시한 모든 작물의 발아율, 근장, 배축장, 초장, 생체중, 건물중, 유묘의 활력이 급격하게 감소하였다. 2. 미국자리공의 autoallelopathy는 고농도(50u l 및 100u l) 첨가시에 나타나기 시작하였으며, 생체중과 건물중은 농도가 증가함에 따라 현저히 감소하였다. 3. 겨자무 잎의 methanol 추출물은 공시한 모든 작물의 초기생장량을 유제시키는 효과는 보였으나, 미국자리공의 잎추출물의 효과보다는 높았다. 4. 겨자무 뿌리의 methanol 추출물 처리는 밀, 미국자리공의 배축장을 농도 증가에 따라 감소시켰으나, 나머지 작물은 증가시켰다. 또한 초장도 밀, 고추, 미국자리공에서는 추출물의 농도가 증가할수록 감소하였으나 그 외의 작물에서는 약간 증가하였다. 5. 미국자리공의 methanol 추출물로부터 재출물한 4종의 분획물 중 ethyl acetate 분획물이 발아율 및 초기생육을 가장 크게 감소시켰다. 6. Ethyl acetate 분획물은 다른 분획물보다 벼, 보리, 배추의 엽록소 함량을 감소시켰다. 7. Ethyl acetate 분획물 100u l l 첨가시에 배추의 유리 proline의 함량은 31.2배 증가하였으며, 추출물농도가 증가할수록 proline 함량이 증가하였다.