• 한국작물학회지
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• 제49권1호
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• pp.7-11
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• 2004

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 $\textrm{L}^{-1}$). 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 $\textrm{kg}^{-1}$ 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.

• 한국작물학회지
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• 제51권1호
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• pp.101-106
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• 2006

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.

• 한국작물학회지
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• 제45권5호
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• pp.310-315
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• 2000

Alfalfa (Medicago sativa L.) plants have been reported to contain water-soluble substances that are autotoxic as well as allelopathic. Laboratory experiment through a petri-dish assay with imbibed seeds was conducted to evaluate both autotoxic and allelopathic effects of alfalfa leaf extracts on the germination and early seedling growth of alfalfa, red clover, crested wheatgrass, and Russian wildrye. Alfalfa seed germination was delayed dependent on extract concentration, with no difference in final germination at 72 hours. Root growth of alfalfa was stimulated up to 14% above control at very low concentrations of both leaf and stem extracts of alfalfa and was significantly reduced at extract concentration of more than 0.5g dry tissue/L (${gL}_{-1}$). Leaf extracts were generally more autotoxic for root growth than were stem extracts. Hypocotyl growth was not affected by all the concentrations of both leaf and stem extracts. Root length of legumes was more sensitive to the autotoxic chemicals from leaf extracts than was germination or shoot length. Hypocotyl growth of two legume plants and plant height of two grasses were not influenced by extracts. Seed germination and root growth of legumes were more inhibited by aqueous extracts of alfalfa leaf than were those of grasses. This result indicates autotoxic effect of alfalfa leaf extracts seems to be greater than allelopathic effect.

• 한국토양비료학회지
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• 제6권4호
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• pp.245-251
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• 1973

세 Alfalfa 품종(品種)(Medicago sativa L. var. Moapoa, Washoe, Lahontan)의 건물생산량(乾物生産量)과 양분흡수(養分吸收)에 미치는 석회(石灰)와 근류균접종효과(根瘤菌接種效果)를 적황색(赤黃色) 사양토(砂壤土)(여기(麗岐) 산토양 pH 4.9)를 사용(使用) Pot시험(試驗)으로 조사(調査)하였다. 1. 무석회구(無石灰區)에서는 발아율이 낮고 그후 생육(生育)이 되지 아니하였으며 Moapa가 가장 강하였다. 2. 무접종구(無接種區)의 건물수량(乾物收量)은 Moapa>Washoe>Lahontan의 순(順)이고 접종효과(接種效果)는 이와 반대였으며 근류균(根瘤菌) 착생에는 큰 차이(差異)가 없었다. 3. 예취시기가 경과함에 따라 무접종구(無接種區)의 수량(收量)이 증가(增加)하고 접종효과(接種效果)가 감소하였으며 질소농도(窒素濃度)에 있어서도 같은 경향이었다. 4. Moapa는 다른 두 품종(品種)에 비(比)하여 N, Ca, Mg의 농도(濃度)가 높은 반면 P, K의 농도(濃度)는 낮았다. 5. Washoe는 Lahontan에 비(比)하여 K가 높고 Ca가 낮으며, Lahontan은 Washoe에 비(比)하여 P가 높고 Mg가 낮다. 6. 접종(接種)에 의(依)해 예취시기가 경과함에 따라 P, K가 감소하였다. 7. Moapa의 다수성(多收性)은 N, Ca, Mg 흡수력(吸收力)이 강한 반면 P, K의 요구도가 적은데 기인하는 것으로 보였다.

• 한국초지조사료학회지
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• 제7권1호
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• pp.25-30
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• 1987

영양액을 사용한 고온하의 Growth chamber에서 근류균을 접종한 Alfalfa의 수양시기별 작물명부위에 대한 실표시비의 영향에 관한여 미국 University of Nevada에서 실험한 결과들을 요약하면 다음과 같다. 초장과 그장에 대한 실표시비의 효과는 높이 인정되었으나 근장에 있어서는 유의성이 없는 다소의 증가을 보였다. 실표시비의 작물의 용접과 건물수량은 무실표구에 비하여 2배이상의 증가를 보여 실표시비의 높은 효과를 나타냈다. 근류의 착생수에 있어서도 실표시비의 효과가 인정되었으나 전구 공히 근류균의 활동이 미흡한 것으로 사료된다. 이상의 결과들은 Alfalfa 분배시 소량의 실표시비의 장려를 암시하는 것 같다.

• 한국초지조사료학회지
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• 제6권3호
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• pp.151-156
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• 1986

저온하(低溫下)의 Growth chamber에서 근유균(根瘤菌)(R-12)를 접종(接種)한 Alfalfa의 수확시기별(收穫時期別) 작물(作物) 각부위(各部位)의 질소시비(窒素施肥)의 효과에 관하여 미국(美國) University of Nevada에서 실험(實驗)한 결과(結果)들을 요약(要略)하면 다음과 같다. 초장(草長), 근장(根長) 및 전장(全長)에 있어서는 질소시비(窒素施肥)의 효과가 나타나지 아니하였으며 작물(作物)의 용적(容積)과 건물수량(乾物收量)은 질소시비(窒素施肥)의 효과를 가져왔다. 질소시비구(窒素施肥區)의 근유균(根瘤菌)의 착생수(着生數)는 무질소구(無窒素區)에서 보다 많았으나 질소고정량(窒素固定量)이 작물(作物)의 원활한 생육(生育)을 위하여서는 미흡(未洽)한 것으로 생각(生覺)된다. 이상의 결과(結果)들은 Alfalfa를 재배시(栽培時) 소량(小量)의 질소시비(窒素施肥)의 필요성(必要性)을 암시하는 것 같다.

• 한국작물학회지
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• 제25권2호
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• pp.38-48
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• 1980

산성토양에 적응할 수 있는 계통으로 캐나다에서 육성보급된 알팔파 근류균 Rhizobium meliloti BALSAC과 일반적으로 알팔파 재배용으로 사용되고 있는 보통 근류균이 알팔파 뿌리혹 형성과 생장에 미치는 효과를 비교하기 위하여 pH 5.4정도의 산성토양을 석회시용으로 pH를 5.9, 6.4로 교정한 뒤 몇가지 종자처리 즉 무처리, 무처리+N시용, 근류균접종, 근류균 접종+석회피복으로써 초자실에서 2개월간 포트시험하여 얻은 결과를 요약하면, 1. 알팔파의 건물량 생산에는 두 근류균계통간에 차이가 없었으나 뿌리혹 형성에 있어서는 Balsac 계통의 효과가 인정되있다. 2. 석회시용으로써 식물체와 뿌리혹의 건물중 및 뿌리혹수가 증가되었으며 뿌리혹의 증가는 주로 측생근에서의 뿌리혹수 증가에 기인하였다. 3. 근류균을 접종하지 않고 질소비료만을 시용함으로써 뿌리혹을 형성한 개체비율, 뿌리혹의 건물중 및 전체뿌리혹수에 대한 굵은 뿌리혹의 상대적 비율이 증가되었다. 4. 상업적으로 생산된 근류균의 종자처리 효과는 일정한 경향을 나타내지 못하였다. 5. 뿌리혹과 관련된 형질조사에서는 상대적으로 그 변이계수가 컸으며 그 변이를 감소시키고 추정치에 대한 신뢰도를 높이기 위해서는 특별한 고려가 있어야 할 것으로 보였다.

• 한국토양비료학회지
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• 제28권2호
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• pp.145-153
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• 1995

우리나라 기후풍토(氣候風土)에 적합한 것으로 생각되는 Al-falfa의 3개품종(個品種)(Dekalb brand 120, Pike, Pioneer brand 5929)에 석회(石灰)를 10a당(當) 무시비(無施肥), 10, 50, 100, 300kg 수준(水準)으로 시용(施用)한 실험(實驗)을 경희대학교(慶熙大學校) 수원(水原)캠퍼스에서 실시(實施)한 결과(結果)를 요약(要約)하여 보면 품종별(品種別) 초장생육(草長生育)은 Dekalb brand 120품종(品種)에 내한 석회시용(石灰施用)의 효과(效果)는 50kg>100kg>300kg>10kg>무시비구(無施肥區) 순(順)으로, Pike 품종(品種)은 50kg>100kg>10kg>300kg>무시비구(無施肥區) 순(順)으로 그리고, Pioneer brand 5929 품종(品種)은 10kg>50kg>300kg>무시비구(無施肥區)>100kg순(順)으로 초장생육(草長生育)이 좋았으며 건물수확량(乾物收穫量)은 Dekalb brand 120 품종(品種)은 50kg>300kg>100kg>10kg>무시비구(無施肥區) 순(順)으로, Pike 품종(品種)은 50kg>10kg>300kg>100kg>무시비구(無施肥區) 순(順)으로, 그리고 Pioneer brand 5929 품종(品種)은 50kg>100kg>10kg>무시비구(無施肥區)>300kg순(順)으로 수량(數量)이 많았다. 다수확(多收穫)은 석회(石灰)의 시용량(施用量)을 공시(共試) 품종(品種) 공히 10a당(當) 50kg 비율(比率)로 시용(施用)한 구(區)에서 나타났으며 수확(收穫)한 식물체내(植物體內)의 무기물(無機物) 성분함량(成分含量)은 석회시용(石灰施用)과 예취시기(刈取時期)와는 일정(一定)한 양상(樣相) 및 유의성(有意性)의 변화(變化)는 없었다. 작물(作物)을 수확(收穫)한 후사용(後使用)한 토양(土壤)의 특성(特性) 및 성분함량(成分含量)에 있어서도 일정(一定)한 양상(樣相)의 변화(變化)는 없었으며, 토양(土壤) pH는 석회(石灰) 시용량(施用量)이 증가(增加)함에 따라서 비례적(比例的)으로 토양(土壤)이 중성(中性) 및 알카리성화 하였다.

• 한국작물학회지
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• 제49권1호
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• pp.30-35
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• 2004

Compositae plants are known to contain biologically active substances that are allelopathic to agricultural crops as well as weed species. Aqueous extracts from leaves of Xanthium occidentale were assayed against alfalfa (Medicago sativa) to determine their allelopathic effects, and the result showed that the extracts applied onto filter paper significantly inhibited seed germination as well as root growth of alfalfa. Untreated seeds germinated in 60h, but extract concentrations greater than 30g $\textrm{L}^{-1}$ delayed seed germination. The extracts significantly inhibited seed germination of alfalfa, and $\beta$-amylase activity of alfalfa and barley seeds during 24-36 hours after treatment. Aqueous extracts of 40 g $\textrm{L}^{-1}$ from X. occidentale were completely inhibited the hypocotyl and root growth of alfalfa. Aqueous leaf extracts showed the highest inhibitory effect and followed by root and stem extracts. Early seedling growth of both alfalfa and barnyard grass (Echinochloa crus-galli) was significantly reduced by methanol extracts. By means of high-performance liquid chromatography, chlorogenic acid and trans-cinnamic acid were quantified as the highest amounts from water and EtOAc fractions, respectively. BuOH and EtOAc fractions of X. occidentale reduced alfalfa root growth more than did hexane and water fractions. The findings of the bioassays for aqueous or methanol extracts reflected that the inhibitory effect of extract was closely related to the level of responsible allelochemicals found in plant extracts.

• Plant Resources
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• 제3권1호
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• pp.71-78
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• 2000

Autotoxicity restricts reseeding of new alfalfa(Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments, often requiring up to a year or more. One solution for reducing autotoxicity would be to select germplasms or cultivars with tolerance to the autotoxic chemical(5) and use genetically breeding program. Bioassay of seed germination and early seedling growth was conducted to evaluate autotoxic responses of 3 varieties of alfalfa to the water-soluble extracts(at 4 and 8g/L) from alfalfa ‘Cody’leaf by using agar and filter paper medium in a petri-dish assay. Root length at 5 days after seeding was more sensitive to the extract than was hypocotyl length or seed germination, and was a better parameter of autotoxic effects of alfalfa leaf extracts. Use of an agar medium gave better sensitivity of root length than did use of filter paper. Evaluating tolerance with percent of control was more important indicator than was mean of root length because of significant variation among varieties in root length of control treatment. Bioassay ranked varieties in the following order of tolerance on the basis of relative root length; “Cody” >“ Pioneer 5373” >“ Alfagraze”. Seedling growth from old “Cody” seed was more sensitive to the autotoxic chemical(5) than was that from newly produced seed.