넓은잎천남성 (Arisaema robustum) 개체군의 잎과 잎생장 패턴

민병미 한국생태학회 1997 Journal of Ecology and Environment Vol.20 No.5

The Arisaema robustum, perennial non-stem herb, population in the temperate forest of Sanseong-ri, Joongbu-myeon, Kyonggi Province was studied for leaf pattern and leaf growth from 1993 to 1995. The area of each side leaflet was larger than that of the apical leaflet in 3-leaflet form plants. But there was no significant difference among the leaflets (apical, 1st side and 2nd side leaflet) in t-testing of the 5-leaflet form plants. The specific leaf area (SLA) of the 3-leaflet form plant was greater than that of the 5-leaflet form plant, and the difference was significant at 0.1%. But differences of SLA value among the leafleats of the same leaflet form plants were minor. The area of leaflets or total leaf area was inversely proportioned to the their SLA values. Especially, the correlation coefficients (CC) between leaf area and SLA in apical leaflets and side leaflets of the 3-leaflet form plant compared to the 1st side leaflets of the 5-leaflet form plants were significant at the level of 1%. The differences between two sides in the dry weight and area of leaflets starting from the apical leaflets were about 5%. The CC values between attributes of the petiole (length and dry weight) and those of leaf blades (dry weight, leaf area and SLA) were high and significant at a 1% level. Especially, The CC value between the dry weight of the petioles and that of the leaf blades was higher than any others (r=0.952). The morphologies of the leaf margins were entire, medium serrate and serrate, and the same plant showed the same type from year to year. The plants usually had one leaf and occasionally 2 leaves. 1-leaf plants usually had 3 or 5 leaflets and occasionally 2 or 4 leaflets. Each year, the ration of individuals having the same number of leaflets was 72%, and that of individuals having a different number of leaflets was 27.54% (an increase of 20.4% and a decrease of 7.1% respectively). In the individuals increasing in the number of leaflets, the ration of individuals shifting from the 3-leaflet from to the 5-leaflet form was 14%. The increase ration of leaf area per individual a year was 37%, and the increase ratios of the plants increasing in leaflets were 60-70% regardiness of leaflet increase. The ratios of leaflet length/breadth were about 1-2, and the variations of those were 0.182-0.286 each year (12-20%).

한지형 마늘의 인경 발육과정에서 식물내생호르몬 Abscisic Acid, Jasmonic Acid 및 당 함량변화

손은영(Eun-Young Sohn),김윤하(Yoon-Ha Kim),김정태(Jung-Tae Kim),장수원(Soo-Won Jang),이인중(In-Jung Lee) 한국원예학회 2011 원예과학기술지 Vol.29 No.1

본 연구는 한지형 마늘인 ‘의성마늘’을 이용하여 장일과 단일 조건에서 재배하여 마늘의 인경 분화 및비대에 미치는 식물 생장 물질의 역할에 대해서 조사하였다. 한지형 마늘의 인경 분화기(4월 16)부터 인경 비대기(4월 24일, 5월 18일)에 엽신과 엽초내 식물내생호르몬 abscisic acid (ABA), jamonic acid(JA) 및 당 함량변화는 장일조건에서 ABA 함량이 단일조건에서 ABA 함량보다 높았고, 엽초내 ABA 함량이 엽신내 ABA 함량보다 높은 것으로 조사되었다. 마늘 생육시기별 ABA 함량은 인편 분화기에서 인경 비대개시기 까지는 큰 변화가 없다가 인경 비대개시기(5월 2일) 이후부터 인경이 비대 되는(5월 18일) 동안 그 함량이 현저히 증가하는 것으로 조사되었다. 반면 단일조건에서는 내생 JA 함량은 변화가 없었으나, 장일조건에서는 인편 분화기(4월 16일)부터 인경 비대개시기(5월 2일)까지 JA 함량은 증가되었다. 엽초내 JA 함량(30.19-53.19ng · g?¹ DW)은 엽신내 JA 함량(12.82-20.41ng · g?¹ DW)보다 높은 것으로 조사되어 엽초 내 JA 함량에 의해 마늘의 인경 비대가 유도되는 것으로 조사되었다. 장일 조건에서 엽신내 당 함량은 인편 분화기(4월 16일)부터 인경 비대개시기(5월 4일)까지 증가되었고, 인경 비대기(5월 4일에서 5월 8일) 동안 감소하였으나, 엽초내 당함량은 인편 분화기(4월 16일)부터 인경 비대기(5월 18일) 까지 서서히 증가되었다. 결론적으로 한지형 의성마늘 생장 양상에 따라 엽초내 호르몬도 변화하는 경향을 보여 호르몬 변화가 마늘 생장과 밀접한 연관이 있음을 보여주었다. This study was performed to investigate the role of plant growth substances on the bulbing of cold type of garlic (Allium sativum L. cv. Uiseongmaneul) during long and short day conditions. The change in endogenous plant hormones such as abscisic acid (ABA), jasmonic acid (JA) and sugar contents in leaf blade and sheath was examined during the growth stage from bulb differentiation (starting at April 16) to bulbing (April 24 to May 18) in cold type of garlic. In the long day condition, ABA contents were higher than short day condition and ABA contents of leaf sheath were higher than leaf blade. ABA contents of growth stage in garlic were not changed during growth stage from April 16 to May 2, however it rapidly increased during bulbing (May 2 to May 18). On the other hand, endogenous JA contents in short day condition did not change in long day condition, it increased from April 16 to May 2. JA contents in the leaf sheath (33.85-62.04 ng · g?¹ DW) were higher than leaf blade (15.39-30.04 ng · g?¹ DW). These results showed that garlic bulb differentiation and bulbing was induced by JA in leaf sheath. In long day condition, total sugar contents in the leaf blade were increased from bulb differentiation (April 16) to bulbing (May 4) and it was decreased during bulbing (May 4 to May 18) while the total sugar content in leaf sheath were gradually increased from bulb differentiation (April 16) to bulbing (May 18). In conclusion, our results showed that there is a significant correlation between the bulb development of garlic and hormonal content in the leaf sheath.

수확후(收穫後) 저장(貯藏)과 조리조건(調理條件)에 따른 배추 가식부위내(可食部位內) NO₃^- 함량변화(含量變化)

孫尙穆 ( Sohn Sang-mok ),尹德勳 ( Yoon Deok-hoon ) 한국유기농업학회 1996 韓國有機農業學會誌 Vol.5 No.1

In order to minimize the daily intake amount of nitrate by Chinese cabbage, the favorate vegetable for Korean, the influences of storage conditions at different temperature and light or dark treatments after post-harvest and effects of cooking temperature and infrared rays on changes of nitrate contents in edible parts of Chinese cabbage were determined. The nitrate contents of midrib and leaf blade in Chinese cabbage during post-harvest were decreased steeply in 2 days and decreased slowly again in 5 days. The temperature treatment to decrease the nitrate contents in midrib and leaf blade of Chinese cabbage were effective as the following of 25℃ > 15°C > -4°C > -10°C. The nitrate contents of midrib and leaf blade were decreased in the timecourse of post-harvest. It is more effective to store in 4°C than in 15 °C, and is more effective in transparent vinyl package than in black vinyl package, but the treatment of light is more effective than the treatment of temperature. The nitrate contents of midrib decreased rapidly by 17.9% in the treatment of 5 days at 15°C. By treatment of 80°C, 90°C, 100°C water, the nitrate contents of midrib were increased slightly, but decreased in leaf blade. It reached 68.5%, 50.6%, 45.9% in the leaf blade respectively by treatment of 80°C, 90°C, 100°C water at 1 min. By infrared rays treatment, the nitrate contents of midrib did not change in 3 min but increased rapidly after 6 min, and in the leaf blade it increased continually after 1 min.

Variegated 담배 (Nicotiana tabacum L. cv. BY-4)의 잎 절편 배양에 따른 재생 식물체의 특성

배창휴,이효연 한국식물생명공학회 1999 식물생명공학회지 Vol.26 No.4

Plantlets derived from leaf blade-segment culture of a variegated tobacco (Nicotiana tabacum L. cv. BY-4) that was induced by a heavy-ion ($^{14}N$) beam irradiation to proembryos, were characterized. When explants from both white and green sections of leaves of the variegated plant were cultured on MS medium containing 0.1 mg/L NAA and 1.0 mg/L BAP, the white sections yielded only white shoots, whereas the green sections generated approximately 47.2% green, 37.4% white and 15.4% variegated shoots. In the F1 generation of a green tobacco derived from the leaf blade-segment culture, the segregation ratio of green to white was 1,651:54. Furthermore, reciprocal crosses showed that all of the progenies was green, indicating that the variegation is not maternally inherited. When the signal intensity of photosynthesis genes was determined by DNA gel blot analysis using the variegated leaves derived from green sections of variegated leaves, there were more of the rbcL, psbA, 16S rDNA and 23S rDNA chloroplast genes in the white sections than the chloroplast genes in wild type and green sections of the variegated plants. 수분 후 담배의 배에 중이온 ($^{14}$ N) beam을 조사하여 유도한 variegated담배의 잎 조직을 기내배양하여 재생된 식물체의 특성을 조사하였다. NAA 0.1mg/L 와 BAP 1/0mg/L를 첨가한 MS배지에서 variegated담배의 잎을 배양하면 백색부위에서는 백색 식물체만이 유도되었으나 녹색부위에서는 녹색 식물체가 47.2%, 백색 식물체가 37.4%, variegated식물체가 15.4% 유도되었다. 재생된 녹색 식물체는 자가수분한 후대 (F$_1$)에서 녹색 식물체 1,651 개:백색 식물체 54개로 분리되었다. 또한 variegated 잎에서 재생된 녹색 식물체와 정상주를 정역교배 한 결과, 전부 녹색체가 분리되었다. 이 결과는 variegated잎의 표현형 유전은 최소한 모성 유전이 아님을 보여준다. Variegated잎의 녹색부위를 배양하여 재생된 variegated식물체의 잎을 이용하여 DNA gel blot한 결과, 엽록체 유전자인 psbA, rbcL, 165 rDNA, 23S rDNA의 양은 흰색부위 잎에서 정상주인 녹색 잎과 variegated식물체 잎의 녹색부위 보다 많았다.

Population Ecology in Natural Syneilesis palmata Stands: 1. Relationship between Flowering and Plant Size

( Byeong Mee Min ) 한국식물학회 2007 Journal of Plant Biology Vol.50 No.4

In this study, the relationship was explored between flowering potential and plant size in a population of Syneilesis palmata (THUNB.) MAX., Usannamul. For this perennial shade-tolerant herb, the flowering rate, plant size, and changes that occurred in the next year after flowering were monitored in two different types of natural stands: moderately shaded (MS; for 11 years) and severely shaded (SS; 7 years). The correlation coefficients (CC) between inflorescence number and other factors, i.e., widths of the first leaf, second leaf, or total leaf breadth, were significant at the 1% level in both stands. In particular, the CC was >0.9 between the number of inflorescences and total leaf breadth. Although the mean flowering rates averaged 6.8% in MS and 8.6% in SS, those values varied widely, ranging from 0 to 53% among years. These rates were not related to petiole length but did increase in proportion to the width of the leaf blade. Flowering began when plants moved beyond the medium size class; the rate in the MS environment was 100% for the largest-sized plants. For plants in the SS, however, the highest rate was 35%. Over the 11 years, 62.8% of all plants in the MS never flowered, while another 30.8% bloomed only once. In comparison, plants observed for 7 years in the SS showed a non-flowering rate of 78.1% and a one-time-only rate of 19.2%. In the next year after flowering, 57.6% of the MS plants exhibited reduced growth while 25.8% of those individuals each split into two plants. In the SS, 37.8% had decreased development the following year, and a mortality rate of 37.8%.

Effect of Variety on Proportion of Botanical Fractions and Nutritive Value of Different Napiergrass (Pennisetum purpureum) and Relationship between Botanical Fractions and Nutritive Value

Islam, M.R.,Saha, C.K.,Sarker, N.R.,Jalil, M.A.,Hasanuzzaman, M. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.6

Five varieties of napiergrasses (Pennisetum purpureum) were fractionated botanically into leaf blade, leaf sheath, stem and head. Chemical composition of each of whole napiergrass and their botanical fractions were determined. Correlation, linear and multiple regressions between botanical fractions and nutritive value of varieties of napiergrass were also estimated. All botanical fractions differed due to the effect of variety. Napier Pusha contained the highest proportion of leaf blade and internode, but the lowest proportion of leaf sheath. Napier Hybrid contained the lowest proportion of leaf blade, but highest proportion of node. Consequently, napier Pusha contained the highest (p<0.01) crude protein (CP, 9.0%), but Napier Hybrid had the lowest CP (7.0%). Chemical composition of whole plant differed significantly (p<0.01; except NFE, p>0.05) due to the variety. Not only the whole plant, chemical composition of most botanical fractions of whole plant differed (p<0.05 to 0.01) due to the variety. The intrarelationships between leaf blade and leaf sheath was negative (r=-0.43). Leaf sheath was also negatively correlated to CP, but positively correlated to ash of whole Napier or their botanical fractions. Leaf blade, on the other hand, increases CP but decreases ash content of whole plant or their fractions. These results, therefore, suggest that napiergrass varieties differ widely in terms of botanical fractions and nutritive value, which may have important implications on intake and productivity of animals. Furthermore, napiergrass varieties should be selected for leaf blade only for a better response.

차광정도(遮光程度) 및 질소시비량(窒素施肥量)이 배추 수량(收量)과 가식부위(可食部位)의 NO₃^- 집적량(集積量)에 미치는 영향(影響)

손상목,오경석,이장석,Soh, Sang Mok,Oh, Kyung Seok,Lee, Jang Seok 한국토양비료학회 1995 한국토양비료학회지 Vol.28 No.2

In order to find out the effects of shading and nitrogen fertilizer on $NO_3^-$ accumulation in the edible parts of chinese cabbage, Cutivar, "Seoul", was cultivated in the pots under glasshouse condition with different rates of shading(0, 15, 30, 50, 75%) and nitrogen fertilization(recommended level, and double rate of recommended level). Leaf length, leaf width, yield (leaf weight), root width and root weight in the 15% shading rate showed the highest value, but decreased in the over 30% shading rates. The highest yield showed in the plot of the 15% shading rate with double rate application of recommended N level. High rate of shading increased the $NO_3^-$ accumulation, especially in midrib and outer leaf compared to leaf blade and inner leaf, respectively. The average $NO_3^-$ accumulation of edible parts of chinese cabbage are $4,872mg\;kg^{-1}$(outer midrib), $2,363mg\;kg^{-1}$(inner midrib), $1,405mg\;kg^{-1}$(outer leaf blade) and $727mg\;kg^{-1}$(inner leaf blade). $NO_3^-$ accumulation of outer midrib in the plots of double application of recommended N level were no difference between shading rate containing $5,000{\sim}6,000mg\;kg^{-1}$ $NO_3^-$, while in the plots of recommended N level it was increased by elevating shading rate. It was concluded that overuse of nitrogen fertiliration for chinese cabbage in glasshouse condition might lead to increase $NO_3^-$ accumulation. It could be advisable to cut out both the out leaf blade and outer midrib which might accumulate the high concentration of $NO_3^-$ before consumption. 차광의 효과가 있다고 알려져 있는 비닐 하우스내에서의 질소다비재배시 일조부속으로 인한 배추의 가식부위내 $NO_3^-$ 집적량의 변화를 밝히고자 차광정도를 달리한 하우스내에서의 질소수순별 처리를 두어 배추 수량과 가식부위내의 $NO_3^-$ 함량을 분석한 결과, 보비구, 배비구 모두 전일광 조건에 비해 15% 차광조건에서 엽장 엽폭, 엽수, 근장, 근폭 근중 및 수량이 최고에 달했으나 30% 이상의 차광조건에서는 오히려 감소하였다. 배추의 최고 수량은 452g으로서 배비구+차광 15% 처리구에서 나타났다. 전일광조건에서 $NO_3^-$ 집적량이 $4,373mg\;kg^{-1}$으로 높았던 외부중록은 차광처리에 따른 $NO_3^-$ 집적량의 증가폭이 적었으나, $NO_3^-$ 집적량이 $1,159mg\;kg^{-1}$, $212mg\;kg^{-1}$으로 낮았던 내부엽중륵 및 내부엽신은 $3,492mg\;kg^{-1}$, $2,435mg\;kg^{-1}$으로 3배, 11.5배로 상승하였다. 차광조건의 경우 엽신보다는 중륵이 내부보다는 외부 가식부위의 $NO_3^-$ 집적량이 많았으며 외부중륵($4,872mg\;kg^{-1}$) >내부중륵($2363mg\;kg^{-1}$) >외부엽신($1.405mg\;kg^{-1}$) >내부엽신($727mg\;kg^{-1}$)의 순으로 낮았다. 15% 까지의 차광에서 보비구의 가식부위별 $NO_3^-$ 집적량은 지상부 지하부 생육 및 수량과 비례적인 증가를 나타냈으나. 배비구의 경우 가식부위인 지상부, 지하부 및 수량의 증가폭 보다 $NO_3^-$ 집적량 증가가 더 컸고, 30%이상의 차광조건에서는 지상부, 지하부 생육 및 수량은 감소하나 오히려 $NO_3^-$ 집적량은 더욱 급격히 증가하였다. 외부엽 중륵의 경우 배비구는 차광정도에 관계없이 $5,000-6,000mg\;kg^{-1}$ 내외에서 일정한 수준을 유지하였으나 보비구는 차광정도가 증가할수록 $NO_3^-$ 집적량도 증가하였다. 결론적으로 비닐하우스내에서의 과다한 질소시비는 바람직 하지 않으며 중륵이 얇은 신품종 배추의 개발보급과 배추이용시 가식부위중 $NO_3^-$ 집적량이 가장 높은 외부엽 엽신과 중륵 부위의 제거가 바람직하다고 판단되었다.

Effects of different day length and wind conditions to the seedling growth performance of Phragmites australis

Hong, Mun Gi,Nam, Bo Eun,Kim, Jae Geun The Ecological Society of Korea 2021 Journal of Ecology and Environment Vol.45 No.2

Background: To understand shade and wind effects on seedling traits of common reed (Phragmites australis), we conducted a mesocosm experiment manipulating day length (10 h daytime a day as open canopy conditions or 6 h daytime a day as partially closed canopy conditions) and wind speed (0 m/s as windless conditions or 4 m/s as windy conditions). Results: Most values of functional traits of leaf blades, culms, and biomass production of P. australis were higher under long day length. In particular, we found sole positive effects of long day length in several functional traits such as internode and leaf blade lengths and the values of above-ground dry weight (DW), rhizome DW, and total DW. Wind-induced effects on functional traits were different depending on functional traits. Wind contributed to relatively low values of chlorophyll contents, angles between leaf blades, mean culm height, and maximum culm height. In contrast, wind contributed to relatively high values of culm density and below-ground DW. Conclusions: Although wind appeared to inhibit the vertical growth of P. australis through physiological and morphological changes in leaf blades, it seemed that P. australis might compensate the inhibited vertical growth with increased horizontal growth such as more numerous culms, indicating a highly adaptive characteristic of P. australis in terms of phenotypic plasticity under windy environments.

한국에 자생하는 들잔디와 갯잔디, 교잡종의 신속한 식별을 위한 ITS TaqMan SNP genotyping assay와 CAPS의 비교 분석 및 각 종의 서식환경별 분포

양대화,정옥철,김유량,강미정,김양지,손지희,한승섭,박미영,진일두,송인자,홍민지,선현진,강홍규,이효연 한국원예학회 2023 원예과학기술지 Vol.41 No.4

In this study, zoysiagrasses found in a major province of the Korean peninsula were collected and identified by molecular techniques. The zoysiagrasses used in this study were collected from mountainous national parks; ‘oreum’ areas; and from inland, coastal and island areas, including marine and coastal national parks on the west, east, and south coasts. Molecular identification was done by means of a cleaved amplified polymorphic sequence (CAPS) marker analysis based on the nrDNA-internal transcribed spacer (ITS) method established by our research team. Additionally, in this study the ITS-based TaqMan single-nucleotide polymorphism (SNP) genotyping assay was developed and used to perform molecular identification more rapidly and accurately. In total, 450 collected zoysiagrass plants were classified into three lines (234 Zoysia japonica plants, 62 Zoysia sinica plants, and 154 Z. japonica and Z. sinica hybrid plants) by molecular identification based on the ITS-based CAPS marker analysis and ITS-based TaqMan SNP genotyping assays. The results of the ITS-based TaqMan SNP genotyping assay were consistent with those of the ITS-based CAPS marker analysis. Both the ITS-based CAPS marker analysis and the ITS-based TaqMan SNP genotyping assay were found to be efficient molecular methods to identify the three species of zoysiagrasses. Specifically, the ITS-based TaqMan SNP genotyping assay method developed inthis study produced results more rapidly compared to the ITS-based CAPS marker analysis method. The habitat distributions of each of the molecularly identified zoysiagrass plants investigated in this study were also assessed. The Z. japonica plants were mainly distributed in mountainous national parks and oreum areas as well as inland and coastal areas. The Z. sinica plants were distributed along the coast and on rocks and stones frequently submerged in seawater. The Z. japonica and Z. sinica hybrid plants were distributed more in the inland, coastal, and island areas than in the mountainous national parks and oreum areas. Findings related to the leaf blade width as a main external morphological classification characteristic of the molecularly identified 450 zoysiagrass plants are described below. The leaf blade width ranged from 4 to 5 mm for the Z. japonica plants, from 2 to 4 mm for the Z. sinica plants, and from 3 to 4 mm for the Z. japonica and Z. sinica hybrid plants. Additionally, some Z. japonica and Z. sinica plants and Z. japonica and Z. sinica hybrid plants with leaf blade widths of 2 to 3, 4 to 5, and from 2 to 3 and 4 to 5 mm, respectively, were also present. Because the ranges of the leaf blade width of each species overlapped, it was difficult to identify the hybrid lines using this metric. The feasibility of the developed molecular identification method for these three species of zoysiagrasses was confirmed in this study 본 연구에서는 한국의 국립공원(산) 및 오름, 서해안 및 동해안, 남해안 부근의 해상국립공원을 포함한 해안 및 섬 등에서 한국잔디류 620점을 수집하였다. 이식, 보존 및 증식 중인 다량의 잔디 450개체는 분자생물학적 분류동정을 수행하였으며, 들잔디(Zj) 234개체, 갯잔디(Zs) 62개체, 들잔디와 갯잔디의 교잡종(H) 154개체로 식별되었다. 본 연구에서 종의 분류 동정 결과는 새로 개발된 ITS 기반 TaqMan SNP genotyping assay 분석과 기존 방법인 ITS 기반 CAPS 분석에서 그 결과가 일치하였으며, ITS 기반의 TaqMan SNP genotyping assay 분석법은 ITS 기반 CAPS 마커 분석법보다 더 신속하게 종 식별 가능함이확인되었다. 분류 동정된 450개체의 들잔디, 갯잔디, 교잡종의 서식환경별 분포를 조사한 결과, 들잔디의 경우 주로 국립공원(산) 및 오름, 내륙, 해안가 등에 분포되었고, 갯잔디의 경우 바닷물에 자주 잠기는 바위나 돌, 해안가의 바닷물이 인접한 부근에서 분포되었으며, 들잔디와 갯잔디의 교잡종은 국립공원 산 및 오름보다 내륙 및 해안가, 섬지역에 걸쳐 다양한 장소에 분포되었다. 기존 외부형태학적으로 주요한 분류 동정의 형질인 잎의 너비(엽폭)가 들잔디와 갯잔디 교잡종의 분류동정에 이용할 수 있는지 분자생물학적으로 분류 동정된 450 개체의 한국잔디류의 주요 외부형태적 분류 특성인 엽폭을 조사한 결과, 엽폭의 크기는대체로 들잔디 4–5mm, 갯잔디 2–4mm, 들잔디와 갯잔디의 교잡종 3–4mm로 분석되었다. 일부 엽폭 크기는 들잔디(2– 3mm)와 갯잔디(4–5mm), 들잔디와 갯잔디의 교잡종(2–3mm과 4–5mm)으로 확인되어 엽폭 크기에 의하여 교잡종을 확실히 분류 동정하기에 쉽지 않았기 때문에 본 연구에서 개발된 신속정확한 분자생물학적 분류 동정법의 필요성을 재확인하였다.

Effect of Carbenicillin on Callus Induction and Regeneration Efficiency of Tissues of Horseradish(Armoracia rusticana)

Chang-Hyu Bae 한국자원식물학회 2001 Plant Resources Vol.4 No.1

The effect of carbenicillin on the dedifferentiation and the regeneration efficiency of plant tissues of horseradish(Armoracia rusticana) was evaluated. Inhibition effect for callus initiation was observed when leaf blade, root and petiole segments were grown on MS medium containing 500 mg/L to 2000 mg/L carbenicillin and 0.5 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D). The regeneration of horseradish shoots from leaf blade, root and petiole explants were decreased as the addition of carbenicillin increased from 1000 mg/L to 2000 mg/L in MS medium containing 0.5 mg/L of 6-benzylaminopurine (BAP) or kinetin. Especially, 500 mg/L carbenicillin treatment significantly inhibited shoot induction when leaf blade explants were grown on hormone-free MS medium. It was suggested that the toxic effects of combinations of carbenicillin and 2,4-D may be due to high auxin activity levels.