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1.
Evaluation of Clove Essential Oil as a Mycobiocide Against Rhizopus stolonifer and Fusarium solani,Tuber Rot Causing Fungi in Yam (Dioscorea rotundata Poir.)
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Modeste Lambert Sameza Lile Christere Nguemnang Mabou Séverin Nguemezi Tchameni Marie Ampère Boat Bedine François Tchoumbougnang Pierre Michel Jazet Dongmo Fabrice Boyom Fekam 《Journal of Phytopathology》2016,164(7-8):433-440
To exploit natural products for plant disease control, the essential oil of Syzygium aromaticum (L.) Merr. & Perr. (clove) was investigated for its antifungal activity against Rhizopus stolonifer and Fusarium solani, the postharvested yam tuber rot pathogens. The essential oil was obtained by hydrodistillation using a Clevenger‐type apparatus. The chemical composition of the oil was determined by gas chromatography and gas chromatography coupled with mass spectrometry. Antifungal activities of the oil were tested in vitro against mycelia growth and spores germination. In situ tests were conducted on healthy yam tubers, and necrosis symptoms were assessed. Results showed that eugenol (79.4%), eugenylacetate (9.2%) and isocaryophyllene (7.0%) were the major components. The oil exerted antifungal activities with total inhibition (TI) of the mycelia growth of R. stolonifer and F. solani was recorded at 200 and 300 ppm, respectively, while TI of spores germination was recorded at 31.25 and 250 ppm, respectively. For the standard fungicide (Ridomil®), TI value of mycelia growth was 1600 ppm for the both pathogens, while TI of spores germination were 200 ppm and 1600 ppm, respectively, for Rhizopus and Fusarium. In situ tests showed complete inhibition of yam tuber rot when the essential oil was applied at 2000 ppm for preventive tests. This oil also reduced significantly (P ≤ 0.05) necrosis development on yam tuber for curative test at the same concentration. Total inhibition of the necrosis by Ridomil (3000 ppm) was observed only for Rhizopus on preventive test. There were positive correlations between the oil concentration and the reduction of necrosis cause by R. stolonifer and F. solani. These findings showed that clove essential oil may serve as environmental friendly bio‐fungicide for the management of postharvest yam tuber rot. 相似文献
2.
Xiaojun Xu Jingli Cheng Yong Zhou Chulong Zhang Xiaoming Ou Weike Su Jinhao Zhao Guonian Zhu 《化学与生物多样性》2013,10(4):600-611
Twenty new trichodermin derivatives, 2a – 5 , containing alkoxy, acyloxy, and Br groups in 4‐, 8‐, 9‐, 10‐ and 16‐positions were synthesized and characterized. The antifungal activities of the new compounds against rice false smut (Ustilaginoidea virens), rice sheath blight (Rhizoctonia solani), and rice blast (Magnaporthe grisea) were evaluated. The results of bioassays indicated that the antifungal activities were particularly susceptible to changes at 4‐, 8‐, and 16‐positions, but low to changes at 9‐ and 10‐positions. Most of these target compounds exhibited good antifungal activities at the concentration of 50 mg l?1. Compound 4 (9‐formyltrichodermin; EC50 0.80 mg l?1) with an CHO group at 9‐position displayed nearly the same level of antifungal activity against Ustilaginoidea virens as the commercial fungicide prochloraz (EC50 0.82 mg l?1), while compound 3f ((8R)‐8‐{[(E)‐3‐phenylprop‐2‐enoyl]oxy}trichodermin; EC50 3.58 and 0.74 mg l?1) with a cinnamyloxy group at C(8) exhibited much higher antifungal activities against Rhizoctonia solani and Magnaporthe grisea than the commercial fungicides prochloraz (EC50 0.96 mg l?1) and propiconazole (EC50 5.92 mg l?1), respectively. These data reveal that compounds 3f and 4 possess high antifungal activities and may serve as lead compounds for the development of fungicides in the future. 相似文献
3.
Mostafa Abdelrahman Sho Hirata Shin-ichi Ito Naoki Yamauchi 《Bioscience, biotechnology, and biochemistry》2013,77(7):1112-1122
To investigate the involvement of Allium roylei metabolites in the plant’s defenses, a comprehensive analysis of the content of cysteine sulfoxides, flavonols, polyphenols, ascorbic acid, and saponins was carried out in the various organs of this species. Metabolomics high performance liquid chromatography (HPLC), spectral-based analysis, and histochemcial studies have given important insight to the validity of saponins as a key component involved in plant protection. The root-basal stem, bulb, and leaf extracts exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with inhibition concentration (IC50) ranging from 0.649 to 0.757?mg/mL. The antimicrobial properties of the saponin and flavonoid crude extracts were evaluated. The saponin extracts demonstrated significant antifungal activity depending on the applied concentration, and the growth inhibition rate of the tested fungal pathogens ranged from 1.07 to 47.76%. No appreciable antibacterial activity was recorded in the same sample. 相似文献
4.
Yi-Gui Qiu Zi-Hui Yang Xue-Bao Sun Dao-Jun Jin Yi-Ming Zheng Jia Li Wen Gu 《化学与生物多样性》2023,20(7):e202300539
To discover novel laccase inhibitors as potential fungicides, twenty-six novel L-menthol hydrazide derivatives were designed and synthesized. In the in vitro antifungal assay, most of the target compounds displayed pronounced antifungal activity against Sclerotinia sclerotiorum, Fusarium graminearum, and Botryosphaeria dothidea. Especially, the EC50 of compounds 3 b and 3 q against B. dothidea was 0.465 and 0.622 mg/L, which was close to the positive compound fluxapyroxad (EC50=0.322 mg/L). Scanning electron microscopy (SEM) analysis showed that compound 3 b could significantly damage the mycelial morphology of B. dothidea. In vivo antifungal experiments on apple fruits showed that 3 b exhibited excellent protective and curative effects. Furthermore, in the in vitro laccase inhibition assay, 3 b showed outstanding inhibitory activity with the IC50 value of 2.08 μM, which is much stronger than positive control cysteine and PMDD-5Y. These results indicated that this class of L-menthol derivatives could be promising leads for the discovery of laccase-targeting fungicides. 相似文献
5.
Abstract Melaleuca styphelioides is considered as medicinal plant. This study was carried out to evaluate for the first time the phytochemical composition and to compare the antifungal activities of essential oil (EOs), methanol and aqueous extracts of M. styphelioides Sm. leaves against three fungi (Aspergillus niger, Rhizopus nigricans and Penicillium digitatum). A total of 10 components of the EO were identified, with the principal compound being methyl eugenol (87.2%). Results of the phytochemical analysis of leaves extract exhibited the presence of different phytoconstituents (phenolic compounds, flavonoids, tannins and anthocyanins). Volatile and non-volatile extracts were found to express dose-dependent inhibition against all tested fungi. Indeed, the EO oil showed significant inhibition of fungal growth and the IC50 was 2.08?µL/mL for A. niger indicating that M. styphelioides leaf EO was particularly effective against this pathogen. The most susceptible species for the aqueous extract was P. digitatum (IC50= 9.54?mg/mL) whereas R. nigricans was found to be more susceptible to the methanolic extract (IC50= 8.31?mg/mL). Thus, the EO and aqueous as well as methanol extracts of M. styphelioides leaves possess antifungal activity and hence, it can be suggested for use in the food or pharmaceutical industries as an alternative to chemical preservatives. 相似文献
6.
Lauge Peter Westergaard Clausen Ulrich Gosewinkel Karlson Stefan Trapp 《International journal of phytoremediation》2015,17(4):369-376
The willow tree (Salix viminalis) toxicity test and a cress seed germination test (Lepidium sativum) were used to determine uptake of F and phytotoxicity of NaF. Concentrations in hydroponic solutions were 0–1000 mg F/L and 0–400 mg F/L in the preliminary and definitive test. A third test was done with soils collected from a fluoride-contaminated site at Fredericia, Denmark. The EC10, EC20 and EC50-values for inhibition of transpiration were determined to 38.0, 59.6 and 128.7 mg F/L, respectively. The toxicity test with soil showed strong inhibition for the sample with the highest fluoride concentration (405 mg free F per kg soil, 75 mg F per L soil solution). The seed germination and root elongation test with cress gave EC10, EC20 and EC50-values of 61.4, 105.0 and 262.8 mg F/L, respectively. At low external concentrations, fluoride was taken up more slowly than water and at high external concentrations at the same velocity. This indicates that an efflux pump becomes overloaded at concentrations above 210 mg F/L. Uptake kinetics were simulated with a non-linear mathematical model, and the Michaelis-Menten parameters were determined to half-saturation constant KM near 2 g F/L and maximum enzymatic removal rate vmax at 9 g/(kg d). 相似文献
7.
Zhiqiang Ge Chunyan Chen Qin Liao Hualong Wu Xiaofei Liu 《Journal of enzyme inhibition and medicinal chemistry》2016,31(2):219-228
A series of novel 3-substituted amino-4-hydroxycoumarin derivatives have been designed and synthesized as chitin synthase (CHS) inhibitors. All the synthesized compounds have been screened for their CHS inhibition activity and antimicrobial activity in vitro. The enzymatic assay indicated that most of the compounds have good inhibitory activity against CHS, in which compound 6o with IC50 of 0.10?mmol/L had stronger activity than that of polyoxins B, which acts as control drug with IC50 of 0.18?mmol/L. As far as the antifungal activity is concerned, most of the compounds possessed moderate to excellent activity against some representative pathogenic fungi. Especially, compound 6b was found to be the most potent agent against Cryptococcus neoformans with minimal inhibitory concentration (MIC) of 4?μg/mL. Moreover, the results of antibacterial screening showed that these compounds have negligible actions to some tested bacteria. Therefore, these compounds would be promising to develop selective antifungal agents. 相似文献
8.
D. Prusky I. Kobiler Y. Fishman J. J. Sims S. L. Midland N. T. Keen 《Journal of Phytopathology》1991,132(4):319-327
A new antifungal compound was isolated from peel and flesh of unripe avocado fruits and identified as 1-acetoxy-2,4-dihydroxy-n-heptadeca-16-ene. The maximal concentration of the anti-fungal monoene in unripe fruits was about 800 μg. g?1 fr.wt. During ripening the monoene decreased to 40 μg. g?1 fr.wt. concomitantly with the appearance of disease symptoms. The concentration of the previously described antifungal diene, 1-acetoxy-2-hydroxy-4-oxo-heneicosa-12,15-diene (Prusky et al. 1982), in avocado peel was 1,600 μg. g?1 fr.wt. in unripe fruits, decreasing during ripening to 120 μg. g?1 fr.wt. At 750 μg. ml?1 the inhibition of germ tube elongation of germinated conidia by the antifungal monoene and the antifungal diene was 15 % and 44 %, respectively. A 1: 1 mixture of both antifungal compounds in concentrations ranging from 50 to 750 μg. ml?1, showed synergistic activity and increased the percent of inhibited germ tubes of germinated conidia up to 15 % over the sum of activities of the separate compounds. The results are discussed in relation to the hypothesis that the antifungal diene and the antifungal monoene are involved in the quiescence of the germinated appressoria of Colletotrichum gloeosporioides in unripe avocado fruits. 相似文献
9.
Zhiqiang Liu Kai Zhang Zhijian Ke Yateng Wu 《Biocontrol Science and Technology》2016,26(11):1538-1551
An endophytic fungus SR06 was isolated from a leaf of Amomum villosum Lour., which had a high antagonistic effect on Colletotrichum musae with an inhibition ratio of 41.20%. The antifungal substances could be secreted into fermentation broth, which had a high inhibitory activity. Strain SR06 was identified as Trametes elegans according to internal transcribed spacer sequence analysis. Response surface methodology (RSM) was used to optimise the process parameters of antifungal substances production. Using the Plackett–Burman design, three variables (glucose, yeast extract and MgSO4·7H2O) exerted significant effects on antifungal substances production. Then RSM experiments were conducted to further optimise the three variables. The optimal medium components were 26.45?g/L glucose, 10?g/L peptone, 14.96?g/L yeast extract and 1.49?g/L MgSO4·7H2O, and the optimal initial pH was 6.0, with a culture temperature of 28°C and a shaking speed of 180?rpm. Under the optimised conditions, a significant improvement in the production of antifungal substances by T. elegans SR06 was accomplished, and the inhibition zone diameter was up to 29.2?mm after culturing for 7d. The average control efficacy of the fermentation supernatant of SR06 against C. musae was 51.29% on banana fruits, which was significantly higher than that of the fungicide carbendazim. 相似文献
10.
Aigui Zhang Jingya Zhou Ke Tao Taiping Hou Hong Jin 《Bioorganic & medicinal chemistry letters》2018,28(18):3042-3045
Sixteen novel pyrazole carboxamides with diarylamines scaffold were designed, synthesized and characterized in detail via 1H NMR, 13C NMR and ESI-HRMS. Preliminary bioassays showed that some of the target compounds exhibited good antifungal activity against Rhizoctonia solani, Fusarium oxysporum, Phytophthora infestans and Fusarium graminearum. Among them, compound 1c exhibited the highest antifungal activities against R. solani in vitro with EC50 value of 0.005?mg/L, superior to the commercially available fungicide fluxapyroxad (EC50?=?0.033?mg/L). And compound 1c (IC50?=?0.034?mg/L) showed higher inhibition abilities against succinate dehydrogenase than fluxapyroxad (IC50?=?0.037?mg/L). This study suggests that compound 1c could be regarded as a potential succinate dehydrogenase inhibitor. 相似文献
11.
Masayuki Katsumi 《Journal of plant research》1973,86(4):267-273
Fluoren-9-carboxylic acid acts not only as an auxin but also as an gibberellin-antagonist. In the standard pea straight test
(S5 section) for auxin it stimulated elongation, the optimum concentration being 10 mg/l. On the other hand, it inhibited elongation at 0.1 mg/l. This inhibitory effect was more marked when younger tissue (S1 section) which also responds to gibberellin was used. Interaction of FCA and IAA in the S5 section has shown that at higher concentration of IAA there seemed to be a suppraoptimal effect, indicating that FCA acted
as an auxin. However, in the S1 section, the stimulating effect of GA3 was markedly inhibited by 0.1 mg/l FCA; 10 mg/l FCA was either additive or less than additive to GA3. In the cucumber hypocotyl test FCA itself was inactive up to 100 μg/plant, but it inhibited the GA3-induced elongation. This inhibition was overcome by increasing the dosage of GA3. In the same material, the IAA-induced elongation was not affected by FCA. These results indicate that whether FCA acts as
an auxin or a gibberellin-antagonist depends on whether the tissue is sensitive to gibberellin and/or auxin. 相似文献
12.
The Cu(II)-tetraaza macrocyclic complex exhibited antimicrobial effects on bacteria, yeasts and filamentous fungi. The highest
antibacterial activity was found withB. subtilis andS. aureus, the respective IC50 values being 18 and 80 μg/L and the MIC values 50 and 1000 μg/L. A concentration of 1 mg/L exerted a bacteriocide effect
onS. aureus. The MIC value forB. subtilis was 250 times lower and forP. aeruginosa 10 times lower than the corresponding values for ampicillin. The Cu-complex was inactive against all tested yeasts. The strongest
antifungal effect was manifested forR. nigricans, with an IC50 value under 0.1 mg/L, whereas inA. alternata the IC50 was 13.5 mg/L. 相似文献
13.
Furanocoumarins are well-known natural products that occur in the most evolved genera of Apiaceae family. This compounds were
found to have cytotoxic, phytotoxic, photosensitizing, insecticidal, antibacterial and high antifungal effects. Aviprin is
considered as a linear furanocoumarin substituted at C8 with an oxygenated prenyl residue. In this study we found that aviprin
is a bioactive compound that exhibits high antibacterial, antifungal and phytotoxic activity. The compound stunted the germination
of lettuce seeds with IC50 value of 0.270 mg/ml. The compound also inhibited the mycelia growth of Sclerotinia sclerotiorum. Aviprin indicated antibacterial activity against tested gram negative and positive bacteria with inhibition zone of 19–23.5
mm. Our results shown that aviprin can play an allelopatic role for plant. 相似文献
14.
Kateřina Štůsková Jakub Pečenka Dorota Anna Tekielska Milan Špetík Zuzana Bytešníková Pavel Švec František Ondreáš Andrea Ridošková Lukáš Richtera Vojtěch Adam Aleš Eichmeier 《The Annals of applied biology》2023,182(2):226-237
Grapevine trunk pathogens (GTPs) cause serious damage to grapevines and have significant economic impacts. There is no effective protection against grapevine trunk diseases. Newly designed AgSe nanoparticles (NPs) and CuSe NPs, single-element Ag NPs, Cu NPs, Se NPs and selected chemicals or chemical agents such as sodium arsenite, 8-hydroxyquinoline, silver nitrate, colloidal silver, Altron Silver fertilizer and silver thiosulfate complex (NH4)3/Ag(S2O3)2 were tested in vitro against two serious GTPs Diaporthe eres, Eutypa lata and Diplodia seriata isolated from walnut. The most significant inhibition of fungal growth was observed for silver nitrate and AgSe NPs, which showed the highest level of half the maximum effective EC50 concentration with the lowest concentrations. In the case of silver nitrate at a concentration of 1000 mg L−1, 79% inhibition of mycelial growth was observed for the pathogen E. lata, 48% for D. seriata and 54% for D. eres. AgSe NPs, in which the concentration of silver is 2588 mg L−1 and that of selenium is 902 mg L−1, showed 68% inhibition of mycelial growth in the pathogen E. lata, 54% in D. seriata and 58% in D. eres. 相似文献
15.
Dr. Sufi Desrini Julien Ducloux Guillaume Hamion Prof. Charles Bodet Dr. Jérome Labanowski Prof. Mustofa Mustofa Prof. Titik Nuryastuti Prof. Christine Imbert Dr. Marion Girardot 《化学与生物多样性》2023,20(8):e202300130
The extracts of five invasive plants were investigated for antifungal and antibiofilm activities against Candida albicans, C. glabrata, C. krusei, and C. parapsilosis. The antifungal activity was evaluated using the microdilution assay and the antibiofilm effect by measurement of the metabolic activity. Ethanol and ethanol-water extracts of Reynoutria japonica leaves inhibited 50 % of planktonic cells at 250 μg mL−1 and 15.6 μg mL−1, respectively. Ethanol and ethanol-water extracts of Baccharis halimifolia inhibited >75 % of the mature biofilm of C. albicans at 500 μg mL−1. The essential oil (EO) of B. halimifolia leaves was the most active (50 % inhibition (IC50) at 4 and 74 μg mL−1against the maturation phase and 24 h old-biofilms of C. albicans, respectively). Oxygenated sesquiterpenes were the primary contents in this EO (62.02 %), with β-caryophyllene oxide as the major component (37 %). Aromadendrene oxide-(2), β-caryophyllene oxide, and (±)-β-pinene displayed significant activities against the maturation phase (IC50=9–310 μ mol l−1) and preformed 24 h-biofilm (IC50=38–630 μ mol l−1) of C. albicans with very low cytotoxicity for the first two compounds. C. albicans remained the most susceptible species to this EO and its components. This study highlighted for the first time the antibiofilm potential of B. halimifolia, its EO and some of its components. 相似文献
16.
[背景] 氨氮浓度会明显影响亚硝化单胞菌的活性,但氨氮浓度对吸附态亚硝化单胞菌菌种的抑制动力学尚缺乏研究。[目的] 研究氨氮浓度对3种吸附态亚硝化单胞菌(Nitrosomonas eutropha CZ-4、Nitrosomonas halophila C-19和Nitrosomonas europaea SH-3)的影响。[方法] 以碳酸钙作为吸附基质,设定氨氮浓度为25-1 000 mg/L,测定3种亚硝化单胞菌(N.eutropha CZ-4、N. halophila C-19和N. europaea SH-3)的亚硝氮积累速率与最大比生长速率,并通过Edwares2模型建立氨氧化的抑制动力学方程。[结果] N. halophila C-19在初始氨氮浓度为50-100 mg/L时的亚硝氮积累最快,N. europaea SH-3的亚硝氮积累则在初始氨氮浓度为50-200 mg/L时最快,而N. eutropha CZ-4则适于在初始氨氮浓度为50-400 mg/L时积累亚硝氮;N. eutropha CZ-4的最大比生长速率出现在初始氨氮浓度为50-400 mg/L时,明显高于N. halophila C-19(25-100 mg/L),而N. europaea SH-3的生长速度在初始氨氮浓度为50-800 mg/L区间内无显著差异;N. europaea SH-3的KI(922.76 mg/L)显著高于N. eutropha CZ-4(597.88 mg/L),而CZ-4的KI又显著高于N. halophila C-19(186.24 mg/L),N. europaea SH-3的Km(72.06 mg/L)显著高于N. halophila C-19(23.23 mg/L)。[结论] 3种吸附态亚硝化单胞菌的生长和氨氧化对氨氮浓度变化的响应存在明显差异,对于认识不同亚硝化单胞菌在不同氨氮浓度污水中的功能并开发相应的工程技术具有重要意义。 相似文献
17.
Khalid Mohammed Khan Zafar S. Saify Muhammad Zarrar Khan Zia-Ullah M. Iqbal Choudhary Atta-ur-Rahman 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):373-379
The synthesis and selective biological screening of 7-hydroxy-4-methyl-2H-chromen-2-one (2), 7-hydroxy-4,5-dimethyl-2H-chromen-2-one (15) and some of their derivatives were carried out. Compound 13 was found to be most potent cytotoxic agent with LD50 = 126.69 μg/ml. In antibacterial assay the compounds showed a broad spectrum of activities. Compound 11 exhibited a very high degree of plant growth inhibition at three levels of concentration. Compound 4 showed very promising antifungal activity against Candida albicans. Compounds 12 and 13 demonstrated excellent antioxidant activity. 相似文献
18.
Dr. Chhavi Sharma Dr. Dinesh Singh Prof. Dr. Ritu Srivastava Prof. Dr. Shailesh Narain Sharma 《化学与生物多样性》2023,20(10):e202300714
In the present work, a bionanocomposite for plant crop protection was prepared by non-toxic biocompatible & biodegradable nanomaterials (Cellulose & TiO2) to utilize its synergistic effects against antimicrobial pathogens. The commercially available microcrystalline cellulose has been reduced to a nanometric scale regime using acid hydrolysis, while the standard TiO2 nano-powder of particle size ~20 nm has been used to prepare their nanocomposite (NC). The antibacterial studies via agar well diffusion method demonstrated that after 72 h of incubation, parent nanomaterials Ncell and TiO2 were not showing any activity against phytopathogens X. campestris pv. campestris, and Clavibacter while the nanocomposite's NC's were still effective depicting both bacteriostatic and bactericidal actions. However, the bacterial growth of biocontrol P. fluorescence was not affected by Ncell, TiO2 NPs and NC after 72 h of incubation. The antifungal testing results via poison food agar assay method suggest that the nanocomposite, along with Ncell and TiO2 NPs, exhibited strong inhibition of fungal growth of Phytophthora Spp at 0.125 mg/ml concentration while for F. graminearum, similar effect was observed at 0.25 mg/ml concentration. The nanocomposite has proved its potential by exhibiting longer & stronger synergistic effects against plant pathogens as a good antimicrobial agent for protection of agricultural crops. 相似文献
19.
Shutian Tao Shaoling Zhang Rong Tsao Marie Thérèse Charles Raymond Yang 《Archives Of Phytopathology And Plant Protection》2013,46(16):1564-1578
Six selected antioxidants (catechin, quercetin-3-galactoside, cyanidin-3-glucoside, pelargonidin-3-glucoside, ellagic and gallic acids) were evaluated in vitro for their antifungal activities and mode of action on Botrytis cinerea Pers., one of the most important pathogens of strawberries. Inhibitory effects were found for all the tested antioxidants, but varied at different fungal developmental stages. Catechin and quercetin-3-galactoside showed linear inhibitory effects on germ tube elongation, with the highest suppression ratios of 54.8% and 58.8% respectively. No significant effect was found on spore germination between treatments and control. Gallic acid showed very strong and linear inhibition on spore germination (r = ?0.95), but the effect diminished after spore germination. Cyanidin-3-glucoside and pelargonidin-3-glucoside provided effective control on the fungi as concentrations increased. The arresting effect of ellagic acid on development of B. cinerea was quadratic. Ellagic acid inhibited germ tube elongation and mycelial growth at its highest and lowest concentrations, while no effects were observed at its medium concentration used in this study. 相似文献
20.
Aspergillus flavus, Alternaria alternata and Fusarium oxysporum were the pathogenic fungi most reduced cereal (barley, sorghum and wheat) seedlings. The pathogens have the ability to produce
aflatoxin B1 and G1, diacetoxyscirpenol, kojic acid and tenuazonic acid that reduced seedling viability. The inhibition dose for 50% reduction
(LD50) was recorded by aflatoxins at 0.83 mg L-1 for barley, 1.74 mg L-1 for wheat and 2.75 mg L-1 for sorghum. Diacetoxyscirpenol produced its inhibition at 1.26 mg L-1 for barley, 3.98 mg L-1 for wheat and 10 mg L-1 for sorghum. Kojic acid induced 50% inhibition at 63 mg L-1 for barley, 105 mg L-1 for wheat and 251 mg L-1 for sorghum. However, tenuazonic acid was less toxic where the toxicity ranged between 79–550 mg L-1. The germination inhibition was more pronounced in barley followed by wheat and was negligible in sorghum for all tested
mycotoxins. This inhibition was attributed to the reduction in the seedling amylase activity, where amylase was also reduced
in the same trend: barley > wheat > sorghum. Grain treated with carboxin-captan and thiophanatemethyl-thiram at 1 g kg-1 grain increased the seedlings vigour of wheat in sterilized soil by 45 and 22%, barley by 24 and 33% and sorghum by 15 and
30%, respectively. These fungicides also had a positive effect on cereal when the soil was inoculated with A. flavus, A. alternata and F. oxysporum, but the improvement was still below normal.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献