• Title, Summary, Keyword: herbicidal activity

Search Result 171, Processing Time 0.05 seconds

Synthesis and Herbicidal Activity of Novel O-quinolinylamidoxime Derivatives (새로운 O-Quinolinylamidoxime 유도체의 합성과 제초활성)

  • Song, Jong-Hwan;Rhie, Soo-Young;Hong, Kyung-Sik;Sung, Nack-Do;Ryu, Eung-K.
    • The Korean Journal of Pesticide Science
    • /
    • v.3 no.3
    • /
    • pp.1-5
    • /
    • 1999
  • Novel O-quinolinylamidoxime derivatives were prepared by replacement of the carboxylic group at the 8 position of quinclorac with various amidoximes. In the flooded paddy conditions, most of the compounds show good herbicidal activity at a rate of 1 kg/ha. Some of them showed excellent herbicidal activity at a rate of 60 g/ha against barnyardgrass (Echinochloa aryicola) with good selectivity on rice. Under the two-leaf stage of barnyardgrass, most of O-quinolinylamidoximes showed good herbicidal activity, expecially compound 3c which showed excellent herbicidal activity barnyardgrass at a rate of 125 g/ha with good rice seletivity.

  • PDF

SUBSTITUENT EFFECT ON THE INHIBITION OF CHLOROPHYLL FORMATION BY N-PHENYL OXADIAZOLIDINEDIONE DERIVATIVES IN CUCUMBER AND SPECULATION ON THE HERBICIDAL ACTION

  • Hwang, Kwang-Jin;Kim, Hyung-Jin;Kim, Jin-Seog
    • Journal of Photoscience
    • /
    • v.3 no.3
    • /
    • pp.137-140
    • /
    • 1996
  • The inhibition of chlorophyll formation in cucumber cotyledons by N-phenyl oxadiazolidinedione derivatives Ia-u showed similar trend as their herbicidal activities. In case of oxadiazolidinedione Iq, with a propargyloxy substituent, both the highest herbicidal activity and inhibitory action(pI$_{50}$ = 6.37) were observed. The accumulation of protoporphyrin IX and cellular electrolyte leakage by oxadiazolidinedione Ia, Ik and Iq were well correlated with their inhibition of chlorophyll biosynthesis. These results suggest that the herbicidal activity of oxadiazolidine Ia-u is originated from the inhibition of chlorophyll biosynthesis.

  • PDF

Herbicidal activity of Korean native plants (I) (살초활성물질 함유 국내 자생식물의 탐색 (I))

  • Kim, Hee-Yeon;Choi, Hae-Jin;Lim, Sang-Hyun;Heo, Su-Jeong;Han, Sang-Sub;Kim, Do-Soon;Hwang, Ki-Hwan;Kim, Song-Mun
    • The Korean Journal of Pesticide Science
    • /
    • v.7 no.4
    • /
    • pp.248-257
    • /
    • 2003
  • The objective of this experiment was to search plant species with herbicidal activity in Korea. Two hundred native plants were collected and their methanol extracts were obtained. Herbicidal activity of methanol extracts were determined by seed bioassay using canola (Brassica napus L.) seedlings. Six plants such as Staphylea bumalda, Wistaria floribunda, Allium victorialis, Rumex crispus, Chionanthus retusa, and Ulmus parvifolia were highly herbicidal: their $GR_{50}$ values were < $1,000{\mu}g\;g^{-1}$. In addition, seventeen plants such as Galium spurium, Zelkova serrata, Campsis grandiflora, Eucommia ulmoides, Sorbus commixta, Deutzia glabrata, Cercis chinensis, Alnus hirsuta, Zanthoxylum schinifolium, Quercus acutissima, Robinia pseudoacacia, Gleditsia japonica, Kerria japonica, Ligustrum obtusifolium, Thuja orientalis, Chamaecyparis obtusa, and Pulsatilla koreana showed herbicidal activity: their $GR_{50}$ values were between 1,000 and $2,000{\mu}g\;g^{-1}$. However, 177 plants showed no herbicidal activity. Plants with herbicidal activity found in this study could be used for weed management and herbicidal compounds in such herbicidal plants could be used as lead compounds in the development of new herbicides.

Herbicidal Activity and Persistency in Aqueous Solution of Ortho Disubstituted Benzenesulfonyl Urea Derivatives (새로운 Ortho 이치환 Benzenesulfonyl Urea 유도체의 제초활성과 수용액중의 잔류성)

  • Kim, Yong-Jip;Chang, Hae-Sung;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
    • /
    • v.38 no.6
    • /
    • pp.570-576
    • /
    • 1995
  • The new sixteen herbicidal N-2-(1-hydroxy-2-fluoroethyl)-6-substituted(X)-benzenesulfonyl-N'-4,6-dimethoxypyrimidinyl-2-yl urea derivatives(S) were synthesized and thier herbicidal activities$(pI_{50})$ in vivo against rice(Orysa Sativa L.), Barnyard grass(Echninochloa orizicola) and Bulrush(Scirpus juncoides) were measured by the pot test under paddy conditions. The structure activity relationship(SAR) were studied using the physicochemical parameters of ortho-substituents(X) and hydrolysis rate constant(logk) and herbicidal activities by the multiple regression technique. The SAR suggested that the herbicidal activities were more dependant on the hydrolysis rate constant(logk>0) than the steric constants $(Es, small width($B_4$) and length($L_1$). Among them, halogens(2 & 5), methyl(15) and non(H) substituent(1) showed higher herbicidal activity for weeds which was not tolerent to rise and weeds. The herbicidal activity was increased and the persistency in aqueous solution was decreased by electron donating(${\sigma}0<0$) groups as ortho-substituent(X). From the relationship equation between herbicidal activity and hydrolysis rate constant, it was assumed that the both reactions would be proceeds with similar process. And the conditions on the ortho substituents to show higher herbicidal activity and the persistency in aqueous solution were also discussed.

  • PDF

3D-QSAR Study on the Influence of Alrylamino (R) Substituents on Herbicidal Activity of Thiourea Analogues

  • Soung, Min-Gyu;Park, Kwan-Yong;Sung, Nack-Do
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.6
    • /
    • pp.1469-1473
    • /
    • 2010
  • Influences of alrylamino (R) substituents on the herbicidal activity ($pI_{50}$) of 1-(4-chloro-2-fluoro-5-propargyloxypheny)-3-(R)-thiourea analogues (1 ~ 35) against the barnyard grass (Echinochloa crusgalli) in the pre-emergence step were discussed quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) as the three dimensional quantitative structure-activity relationship (3D-QSAR) method. The statistically most satisfactory CoMFA models for the herbicidal activity against the barnyard grass had the better predictability ($r^2{_{cv.}}$) and correlativity ($r^2{_{ncv.}}$) than those of CoMSIA models. The optimized CoMFA model 1($r^2{_{cv.}}$ = 0.531 & $r^2{_{ncv.}}$ = 0.931) with the sensitivity to the perturbation (${d_q}^{2'}{dr^2}_{yy'}$ = 1.081) and the prediction ($q^2$ = 0.475) produced by a progressive scrambling analyses were not dependent on chance correlation. And statistical qualities with the atom based fit alignment (AF) were slightly higher than those of the field fit alignment (FF). According to the optimized CoMFA model 1, the contribution ratio (%) of the steric field (76.9%) on the herbicidal activity of the Thioureas was three-fold higher than that of the electrostatic field (20.1%) and the hydrophobic field (3.0%) had the least influence. A steric favor group is on the vicinity of the nitrogen atom in alrylamino (R) substituent, and a steric disfavor group is on the outer side of alrylamino (R) substituent. Thus, as the size of alrylamino (R) substituent increases, so does the herbicidal activity of the substituent.

Structure-activity relationships on the herbicidal activity of the 2,3-dihydro-2,2,4,6,7-pentamethylbenzofuran-5-yl substituents in 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives (5-Benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hyoxycyclohex-2-en-1-one 유도체 중 2,3-dihydro-2,2,4,6,7-pentamethylbenzofuran-5-yl 치환체들의 제초활성에 관한 구조-활성관계)

  • Sung, Nack-Do;Song, Jong-Hwan;Kim, Hyoung-Rae
    • The Korean Journal of Pesticide Science
    • /
    • v.4 no.3
    • /
    • pp.47-51
    • /
    • 2000
  • A some of synthesized 2,3-dihydro-2,2,4,6,7-pentamethylbenzofuran-5-yl substituents in 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives as substrates were found to show herbicidal activity against rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) with post emergence under submerged conditions. The substrate with $R_{1}$=methyl substituents, $1{\sim}5$ showed the higher herbicidal activity to the seed, 3 leaf stage of rice plant and barnyard grass. The structure activity relationships (SARs) on the herbicidal activity of $R_{1}$ and $R_{2}$ on the azomethine bond in substrate were analysized. In the condition of $R_{1}$ groups are same, the herbicidal activity against 3 leaf stage of rice plant were governed by the optimal hydrophobicity $(logP)_{opt.}=4.57$. Whereas, in the case of barnyard grass, the herbicidal activities were largely dependent upon the steric effect, $B_{2}$ constant than hydrophobicity. In order to take the selective herbicidal activity between rice plant and barnyard grass, it is assumed that the (S) should be a round shape with higher hydrophobicity (logP>4.57) than optimal value. Also, the $R_{1}$ groups must be small and the $R_{2}$ groups are advisable to be unsaturate.

  • PDF

Herbicidal Activities of Phenylvinylsulfone Derivatives (Phenylvinylsulfone 유도체의 제초활성)

  • Yu, Seong-Jae;Jeon, Dong-Ju;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
    • /
    • v.38 no.1
    • /
    • pp.90-94
    • /
    • 1995
  • Post emergence herbicidal activities$(pI_{50})$ of X-substituted phenylvinylsulfone derivatives(S) in-vivo against rice(Oryza sativa L.), Barnyard grass(Echinochloa crus-galli) and Pickerelweed(Monochoria vaginalis Presl) were measured by the pot test under paddy conditions. The (S) showed herbicidal symptom rapidly with lower activity(average $pI_{50}=2.0$) as proherbicide, which was excellent tolerance to rice. The structure activity relationships(SAR) were analyzed using such a physicochemical parameters as hydrophobic$({\pi})$ and molecular orbital(MO) quantity by the multiple regression technique, and discussed with quantum pharmacology. The herbicidal activities were related to the hydrophobic$({\pi})$ effect of X-substituent and orbital(HOMO & LUMO) energy. In case of Pickerelweed, the effect was rationalized by parabolic function of ${\pi}$ constant, where the optimal value of ${\pi}$ was 1.10. An increase in hydrophobicity and negative orbital energy by the electron attracting X-substituent may contribute to the herbicidal activity. Based on results proposed from SAR analysis, the mode of herbicidal action could be assumed.

  • PDF

Influences of Temperature and Light on the Herbicidal Activity of Bleaching Herbicides (Bleaching Herbicides의 제초활성에 영향을 미치는 온도 및 광의 영향)

  • Kim, J.S.;Na, J.Y.;Cho, K.Y.
    • Korean Journal of Weed Science
    • /
    • v.9 no.3
    • /
    • pp.230-237
    • /
    • 1989
  • This research was carried out to investigate the influences of temperature and light on the herbicidal activity of oxyfluorfen, oxadiazon and paraquat. Increased temperature from 10 to $35^{\circ}C$ resulted in increase of herbicidal activity in whole plants or leaf discs treated with herbicides. It seemed that temperature affected herbicide penetration into and reaction to the action site rather than appearance process of herbicidal activity (maybe membrane peroxidation after being absorbed. The activity of compounds tested increased with increased light intensity. Paraquat showed similar activities regardless of light qualities but oxyfluorfen and oxadiazon showed the highest activities in blue light spectrum, indicating that they seemed to be closely related to chlorophyll biosynthesis rather than carotenoid biosynthesis or electron transport systems of photosynthesis and respiration.

  • PDF

Isolation of Herbicidal Compound from Bulbs of Lycoris chinensis var. sinuolata K.H.Tae & S.T.Ko (진노랑상사화 인경으로부터 살초활성 물질의 분리)

  • Jang, Ho-Jin;Kim, Kun-Woo
    • Korean Journal of Weed Science
    • /
    • v.30 no.4
    • /
    • pp.437-444
    • /
    • 2010
  • This study was conducted to determine the herbicidal activity of allelochemicals and identify herbicidal compounds in bulbs of Lycoris chinensis var. sinuolata. Methanol extract was purified by a series of silica gel flash column chromatography and HPLC. The final HPLC gave two active fractions and an herbicidal compound was obtained. By GC/MS analysis, the herbicidal compound was identified as montanine ($O^2$-methyl pancracine), an isoquinoline alkaloid. Montanine showed 100% of growth inhibition on the shoot and root of barnyardgrass (Echinochloa crus-galli) seedlings at $50\;{\mu}g\;mL^{-1}$ as compared with the control.

2D-QSAR and HQSAR Analysis on the Herbicidal Activity of New Cyclohexanedione Derivatives (새로운 Cyclohexanedione계 유도체의 제초활성에 관한 2D-QSAR 및 HQSAR 분석)

  • Kim, Yong-Chul; Hwang, Tae-Yeon;Sung, Nack-Do
    • The Korean Journal of Pesticide Science
    • /
    • v.12 no.1
    • /
    • pp.9-17
    • /
    • 2008
  • QSARs (Quantitative structure-activity relationships) between a series of new cyclohexanedione derivatives (5-benzofuryl-2-[1-(alkoxyimino)-alkyl]-3-hydroxycyclohex-2-en-1-ones) and their herbicidal activity against Rice plant (Oryza sativa L.) and Barnyard grass (Echinochloa crus-galli.) were discussed quantitatively using 2D-QSAR and holographic (H) QSAR methods. Generally, the HQSAR models have better predictability and fitness than the 2D-QSAR models. The herbicidal activities against Barnyard grass with 2D-QSAR II model were dependent upon Balaban indice (BI) of molecule and hydrophobicity of $R_1$ and $R_3$ group. And also, the $R_3=ethyl$ group, according to the information of the optimized HQSAR IV model, was more contribute to the herbicidal activities against Rice plant, while the 5-(cyclohex-3-enyl)-2,3-dihydrobenzofuran ring part was not contribute to the herbicidal activities against two plants.