• 한국환경과학회지
• /
• 제1권2호
• /
• pp.145-155
• /
• 1992

The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna anguluris seedlings. Expose to 50 $\mu$N Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of AA reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. 5-Aminolevulinic acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• 제1권2호
• /
• pp.145-155
• /
• 1997

The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna angularis seedlings. Expose to 50 uM Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of Al reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. $\delta-Aminolevulinic$ acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

• 한국환경과학회:학술대회논문집
• /
• 한국환경과학회 2003년도 봄 학술발표회 발표논문집
• /
• pp.261-262
• /
• 2003

Sunflower(Helianthus annuus L.) seedings were de-rooted and grown in nutrient solutions providing either deficient or sufficient boron supply and supplemented with aluminum. Increasing concentrations of aluminum in the nutrient medium caused progressive inhibition of root growth and a parallel increase in proline level of roots. Elevated boron levels improved root growth under toxic aluminum conditions and produced higher proline contents. Exogenous ascorbate improved adventitions root growth in plants supplied with insufficient boron and aluminum. These findings suggest that root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• 한국환경과학회지
• /
• 제12권11호
• /
• pp.1189-1196
• /
• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• Journal of Applied Biological Chemistry
• /
• 제59권2호
• /
• pp.159-164
• /
• 2016

Plant growth regulator is an essential pesticide to date while the available active ingredient is not well understood unlike fungicide, insecticide and herbicide. This study was aimed to evaluate a new chemical class of plant growth regulator, and the total of 92 benzene derivatives were screened for their germination and early stage of the root growth regulation on Brassica campestris. Thirty benzaldehydes, nine acids, one amide, and one ester showed potent root growth inhibitory activity (>70 % inhibition) while only salicylaldehyde showed potent germination inhibition ($IC_{50}=81.2mg/L$) suggesting that benzaldehyde was a key module candidate for the growth inhibition. Benzaldehydes were further evaluated for root growth inhibition. 2,3-Dihydroxybenzaldehyde and salicylaldehyde showed $IC_{50}$ values of 8.0 and 83.9 mg/L, respectively. On the other hand, salicylaldehyde, and 2,4,5-trihydroxybenzaldehyde were found to have root growth promotion effects less than 10 mg/L. This result suggests that the benzaldehyde is a new class candidate for plant growth regulator.

• 한국작물학회지
• /
• 제45권2호
• /
• pp.134-138
• /
• 2000

Most parts of alfalfa plant have been reported to contain autotoxic substances that inhibit seed germination and early seedling growth, however, the chemical(s) is not still studied much. Effect of seed leachates of 'Vernal' alfalfa (Medicago sativa L.) was evaluated for inhibition of alfalfa germination and root growth through bioassay. Alfalfa seeds were extracted in 1 L deionized water for 1 h after soaking and the leachates caused to reduce root length of alfalfa significantly as the soaking time increased. Crude seeds at 4 g L$L^{-1}$ exudated autotoxins that reduce significantly root length by 34 % compared to the control, when the seeds soaked in deionized water for 24 h. However, the extracts did not affect final germination as well as speed of germination. Extracts from ground seeds significantly reduced speed of germination (GT 50) and root length. The results indicate that release of autotoxic substances from seeds during seed imbibition was increased with increase of soaking time and seed amount, and that autotoxicity was more occurred in ground seeds than in crude seeds.

• 한국잡초학회지
• /
• 제17권4호
• /
• pp.407-412
• /
• 1997

약용작물의 allelopathy 효과를 구명하기 위하여 메탄올 추출물을 이용하여 생물검정한 결과 피의 발아, 신초 및 뿌리생육 억제는 공시식물, 사용부위, 사용농도에 따라 다르게 나타났는데 피의 발아, 신초 생장 및 뿌리는 천궁 및 감초 뿌리추출물에 의해서 가장 억제가 되었다. 1g 농도에서 피의 발아, 신초생장, 뿌리생장이 각각 88%, 95%, 100%, 감초추출물에서 87%, 96%, 100% 억제되었다. 천궁의 부위별 억제정도는 뿌리에서 가장 크게 나타났는데 0.5g에서 피는 완전히 억제가 되었으나 줄기 잎추출물에서는 억제효과가 크지 않았다. 용매극성별 피의 억제 정도는 에틸아세테이트에서 가장 크게 억제되었다. 피의 발아는 3분획 모두 억제가 되지 않았으나 신초 및 뿌리생장은 에틸아세테이트분획이 에틸에테르나 메탄올 분획보다 억제가 더 컸다. 이상의 결과에서 천궁뿌리에 함유하고 있는 allelochemicals은 중간정도의 극성을 띤 물질일 것으로 사료되며 allelochemicals의 분리정제에 귀중한 재료가 될 것으로 사료된다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제26권5호
• /
• pp.1-8
• /
• 2021

A series of pot experiments were conducted to quantitatively estimate inhibitory effects of reclaimed soil on the growth of Lentil (Lens culinaris) with two soils remediated by land farming (DDC) and low temperature thermal desorption(YJ), respectively. After cultivation in a growth chamber for 8 days, plants were harvested for the analysis of 8 indices including chlorophyll-a and carotenoid in leaves, shoot fresh weight, root dry weight, root length, number of later roots, specific root length (SRL) as well as germination rate in comparison to control experiment conducted on nursery soil. Root length was estimated by SmartRoot program from the digital images of the roots. The results showed germination rate on YJ and DDC soil decreased 29 and 71%, respectively. In comparison to the control, the averaged value of the 8 indices for YJ and DDC soil showed overall growth inhibition was 48 and 68%, respectively. When the same experiment was conducted with 25% (W/W) vermiculate amended soil, plant growth on each soil was comparable to that of the control. The results implies reclaimed soils requires additional processes and/or amendments to reuse for plant growth.

• 농약과학회지
• /
• 제18권4호
• /
• pp.439-442
• /
• 2014

신나밀계 화합물은 다양한 생물에 넓게 분포하는 생물 2차대사산물로 잘 알려져 있으며, 여러 생리활성이 규명되었다. 하지만, 작물의 생장조절기능성 연구결과는 잘 알려져 있지 않아, 본 연구에서는 신나밀기를 갖는 acid, amide, alcohol, aldehyde, ester등 46종의 유도체를 대상으로 발아와 유근생장억제능을 비교평가 하였다. 시험 결과, cinnamyl group을 기본 골격으로 하는 화합물의 경우 carboxylic acid group보다는 ester, amide, aldehyde와 같은 functional group에서 유근생장 억제능이 쉽게 관찰되는 것으로 확인되었다. 또한, EWG는 meta-position에 위치할 때 가장 효과가 높은 것으로 확인되었으며, cinnamamide, 3-chlorocinnamic acid와 4-methoxycinnamaldehyde는 100 mg/L 미만의 처리농도에서 배추에 대한 발아억제를 일으키지 않으며, 유근생장 생장억제기능성이 높아 작물 생장억제제로 사용가능한 cinnamyl 유도체임을 확인하였다.

• BMB Reports
• /
• 제53권3호
• /
• pp.160-165
• /
• 2020

The root meristem of Arabidopsis thaliana is protected by the root cap, the size of which is tightly regulated by the balance between the formative cell divisions and the dispersal of the outermost cells. We isolated an enhancer-tagged dominant mutant displaying the short and twisted root by the overexpression of ZINC-FINGER OF ARABIDOPSIS THALIANA1 (ZAT1) encoding an EAR motif-containing zinc-finger protein. The growth inhibition by ZAT1 was shared by ZAT4 and ZAT9, the ZAT1 homologues. The ZAT1 promoter was specifically active in the outermost cells of the root cap, in which ZAT1-GFP was localized when expressed by the ZAT1 promoter. The outermost cell-specific expression pattern of ZAT1 was not altered in the sombrero (smb) or smb bearskin1 (brn1) brn2 accumulating additional root-cap layers. In contrast, ZAT4-GFP and ZAT9-GFP fusion proteins were distributed to the inner root-cap cells in addition to the outermost cells where ZAT4 and ZAT9 promoters were active. Overexpression of ZAT1 induced the ectopic expression of PUTATIVE ASPARTIC PROTEASE3 involved in the programmed cell death. The EAR motif was essential for the growth inhibition by ZAT1. These results suggest that the three related ZATs might regulate the maturation of the outermost cells of the root cap.