Secondary metabolites of the culturable endophytic fungus Penicillium chrysogenum and their plant growth regulator activity

Thirteen of the new synthetized 2-R substituted benzothiazole derivatives have been tested for plant growth regulatory (PGR) activity. The effect on growth elongation was studied on wheat coleoptile segments Triticum aestivum L. cv. Blava, and on the hypocotyl and roots in cucumber Cucumis sativum L. cv. Evita. The formation and number of adventitious roots and the length of hypocotyl in Vigna radiata (L.) Wilczek and, the effect on the length of stem, fresh and dry mass in buckwheat Fagopyrum esculentum Moench. cv. Pyra were evaluated. Cytokinin activity was determined on segments of barley leaves Hordeum vulgare L. cv. Jubilant on the basis of senescence inhibition and chlorophyll content. The benzothiazole derivatives were tested in the range of 10<sup>–3</sup>–10<sup>–7</sup>M concentrations, and PGR activity was compared with indole-3-acetic acid, indole-3-butyric acid and 6-furfurylaminopurine. All tested derivatives showed different auxine-like effects on elongation growth of plants and the stimulative effects were found to depend on applicable concentrations. At higher concentration rates, derivatives acted as growth retardants and inhibited the length of cucumber hypocotyl and roots. The derivatives increased the formation of adventitious roots of mung bean hypocotyl cuttings, as well as stem elongation and production of fresh and dry mass of buckwheat. Cytokinin activity was confirmed in one derivate only with a significant effect on the inhibition of leaf senescence and higher chlorophyll content. The tested benzothiazole derivatives may be characterized as biologically active substances with dominant auxine-like growth promoting activity

A series of novel cyanoacrylates containing furan or tetrahydrofuran moieties were synthesized, and their structures were characterized by 1H NMR, elemental analysis, and single-crystal X-ray diffraction analysis. The herbicidal, plant growth regulatory, fungicidal, and antiviral activities of these cyanoacrylates were evaluated. The results of herbicidal activities showed that most of these cyanoacrylates exhibited higher herbicidal activities against dicotyledonous weeds than monocotyl-edonous weeds, and the compounds containing the tetrahydrofuran moiety gave higher herbicidal activities than corresponding furan analogues; (Z)-ethoxyethyl 2-cyano-3-isopropyl-3-(tetrahydrofuran-3-yl)methaneaminoacrylate showed excellent herbicidal activities against amaranth pigweed in postemergence treatment at a dose of 375 g/ha. At the same time, these cyanoacrylates had interesting plant growth regulatory activities, and some compounds stimulated radicle growth of cucumber, whereas some compounds had an inhibitory effect. These cyanoacrylates showed fungicidal activities as well.

Plant growth inhibitory activities by secondary metabolites isolated from Latin American flora

Journal Article Structure and Biological Activity of Plant Growth Regulators Produced by Penicillium sp. No. 31f Get access Yasuo Kimura, Yasuo Kimura Department of Bioresource Science, Faculty of Agriculture, Tottori University, Koyama, Tottori 680, Japan Search for other works by this author on: Oxford Academic Google Scholar Kenichi Shiojima, Kenichi Shiojima Department of Bioresource Science, Faculty of Agriculture, Tottori University, Koyama, Tottori 680, Japan Search for other works by this author on: Oxford Academic Google Scholar Hiromitsu Nakajima, Hiromitsu Nakajima Department of Bioresource Science, Faculty of Agriculture, Tottori University, Koyama, Tottori 680, Japan Search for other works by this author on: Oxford Academic Google Scholar Takashi Hamasaki Takashi Hamasaki Department of Bioresource Science, Faculty of Agriculture, Tottori University, Koyama, Tottori 680, Japan Search for other works by this author on: Oxford Academic Google Scholar Bioscience, Biotechnology, and Biochemistry, Volume 56, Issue 7, 1 January 1992, Pages 1138–1139, https://doi.org/10.1271/bbb.56.1138 Published: 01 January 1992 Article history Received: 04 December 1991 Published: 01 January 1992

Peanut is a globally important legume crop consumed in various forms due to its high nutritional value. However, peanut production faces challenges, particularly under drought conditions, resulting in reduced flowering, peg and pod formation. This study aimed to investigate the changes in morphology, anatomy and activity of plant growth regulators during flowering, peg development and pod formation in peanuts, using the VD01-2 cultivar. The objective of the study was to explore the application of plant growth regulators to optimize flowering, peg development and increase pod yield in peanuts. The peanuts were cultivated at the Ho Chi Minh City High-Tech Agriculture Park under the following conditions: 150 ± 20 Klux light intensity, 45/26 ± 2 °C temperature and 35/80 ± 5 % humidity. The experimental soil composition was 63.4 % sand, 28.5 % silt and 8.1 % clay, with 24.91 g kg-1 organic matter, 0.165 % total nitrogen, 0.062 % phosphorus and 0.93 % potassium. Statistical analysis of the data revealed an increase in auxin and gibberellin activity during flowering, which contributed to peg elongation. However, as the peg entered the soil and formed the pod, the activity of these plant growth regulators decreased. Additionally, the combination of 50 mg L-1 IAA (indole-3-acetic acid) and 150 mg L-1 GA3 (gibberellic acid) effectively enhanced the development of flowers, pegs and pods in peanut plants under drought-stress conditions. Furthermore, this combined treatment resulted in an increase in the lipid content of the seeds from 545.2 mg to 570.0 mg/g of weight. These findings have the potential to improve peanut productivity under drought conditions, addressing the challenges faced in peanut production.

Treating grains and roots of wheat seedlings with supernatants of different aged cultures of Streptomyces atroolivaceus stimulated plant growth. The treatment resulted in increased shoot elongation, shoot fresh and dry weights, and root fresh and dry weights but suppressed the depth of the root system. The supernatants resulted in increased shoot DNA but not root DNA. Shoot and root contents of RNA and protein were also enhanced. Effects probably caused by activity of plant growth regulators.

Several 8-oxabicyclo[3.2.1]oct-6-en-3-one derivatives have been prepared via the [3 + 4] cycloaddition between the oxyallyl carbocation generated from polybromoketones and alkylfurans. The selective effects of these compounds on the radicle growth of a monocotyledon [sorghum (Sorghum bicolor L.)] and a dicotyledon [cucumber (Cucumis sativus L.)] were evaluated. All of the test compounds, at the concentration of 100 μg mL-1, stimulated cucumber root growth (5−30%), but they inhibited sorghum root growth (23−56%). None of the compounds had any effect on the percent of germination of the species tested. Keywords: Plant growth regulators; oxyallyl cation; cucumber; sorghum

This work is aiming at the preparation of new bioactive compounds from α-pinene as starting material. To this purpose, the intermediates (disubstituted phenyl acylamino thioureas, class G) were cyclized to dithiadiazoles (class H). The intermediates and target compounds were analyzed by Fourier transform infrared, 1H nuclear magnetic resonance (NMR), 13C NMR, and electrospray ionization-mass spectrometry and elemental analysis. The bioassay experiments showed that the compounds G and H have herbicidal, fungicidal, and plant growth-regulating activities. The compounds 2,2′-dimethylphenyl thiadiazole and 3,3′-dimethylphenyl thiadiazole exhibited a growth inhibition activity of 72% and 68% against the root of rape (Brassica campestris L.) at a concentration of 100 μg ml-1 (60–79% inhibition level). The compound 4,4′-dichlorophenyl acylamino thiourea displayed an inhibition activity of 75% against Physalospora piricola at a concentration level of 50 μg ml-1 (60–79% inhibition level).

While screening fungi for the production of plan growth regulating substances we isolated a fungus, late identified as Penicillium corylophilum Dierckx, from tw sources.The first was a laboratory culture of Dendrc stilbella macrospora which had been contaminated wit P. corylophilum (ATCC accession No. 64543) and th second was an in vitro tissue culture contaminant c peanut, Arachis hypogaea L. (ATCC accession No. 64869B ulk culture of each organism, through solid fermen tation, followed by extraction, led to the isolation of 3,7 dimethyl-8-hydroxy-6-methoxyisochroman (DHMI) (Fi£ 1).The metabolite inhibited the growth of etiolated whea coleoptiles.Earlier, DHMI was reported to have beeisolated from moldy millet hay implicated in the death o cattle,1] but the metabolite was not tested in plants Because DHMIhas a functional hydroxyl group at C8, w R=H : 3,7-dimethyl-8-hydroxy-6-methoxyisochroman R=CH3CO: 8-acetoxy-3,7-dimethyl-6-methoxyisochroman R=CH3:6,8-dimethoxy-3,7-dimethylisochroman

Fourteen new 1H‐1,2,4‐triazole derivatives containing pyridine moiety were synthesized by condensation of 1‐(pyridine‐3‐yl)‐2‐(1H‐1,2,4‐triazol‐1‐yl)ethanone with aryl aldehydes, and their reaction conditions were studied. The title compounds were screened for their antibacterial and plant growth regulatory activities. The screening data revealed that most of the compounds showed some antifungal and plant growth regulatory activities. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:376–380, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20308

Journal Article 3,7-Dimethyl-8-hydroxy-6-methoxy-isochroman from Penicillium corylophilum: Plant Growth Regulatory Activity Get access Horace G Cutler, Horace G Cutler USDA, ARS, Richard B. Russell Center, P. O. Box 5677, Athens, GA 30613, U.S.A Search for other works by this author on: Oxford Academic Google Scholar Richard F Arrendale, Richard F Arrendale USDA, ARS, Richard B. Russell Center, P. O. Box 5677, Athens, GA 30613, U.S.A Search for other works by this author on: Oxford Academic Google Scholar Patsy D Cole, Patsy D Cole USDA, ARS, Richard B. Russell Center, P. O. Box 5677, Athens, GA 30613, U.S.A Search for other works by this author on: Oxford Academic Google Scholar Elmer E Davis, Elmer E Davis American Type Culture Collection, 12301 Parklawn Drive, Rockville, MD 20852, U.S.A Search for other works by this author on: Oxford Academic Google Scholar Richard H Cox Richard H Cox Philip Morris USA, Research Center, P. O. Box 26583, Richmond, VA 23261, U.S.A Search for other works by this author on: Oxford Academic Google Scholar Agricultural and Biological Chemistry, Volume 53, Issue 7, 1 July 1989, Pages 1975–1977, https://doi.org/10.1080/00021369.1989.10869594 Published: 01 July 1989 Article history Received: 28 October 1988 Published: 01 July 1989

Aim. To investigate the ability of our phytopathogenic fungal strain 502, earlier preliminarily identified as the phytopathogen Plectosphaerella melonis (syn. Acremonium cucurbitacearum), to have phytotoxic and/or plant growth regulatory activity. Methods. The phytotoxicity of strain 502, was studied by bioassays using the test cultures of corn (Zea mays L.), garden cress (Lepidium sativum L.), cucumber (Cucumis sativus L.), and onion (Allium cepa L.). The cytotoxicity and genotoxicity of the fungus were estimated using the Allium cepa-test. The mitotic index of the, the duration of mitosis phases, and the frequency of aberrant ana-telophases of Allium cepa L. roots meristem was also investigated. For this purpose, strain 502, was grown in the following culture media: synthetic Raulin-Thom medium for 10 days at 26 ± 2 °С. Cell-free filtrate (culture fluid) was used for the study. Ethylene production was quantified in culture filtrate using gas-chromatography meth- od. Ethylene measurement was performed every 7 days during 8 weeks. The determination was carried out using a gas chromatograph «Agilent Technologies 6850» (USA) fitted with a flame ionization detector, using commercial ethylene as a standard for identification and quantification Every experiment had three repeats. The reliability of experimental data was assessed by statistical methods using Statistica 12 (Stat-Soft Inc., USA). Results. Undiluted culture fluid (obtained by growing the fungus on liquid wort) of our strain 502 inhibited the growth of Z. mays seedlings by 14 %, L. sativum seedlings by 18 % (1 : 100 dilution) and stimulated the growth of L. sativum roots by 54 and 41 % (1 : 10 and 1 : 100 dilutions, respectively). The culture fluid, obtained by growing the fungus on Raulin-Thom’s synthetic agar, demonstrated a slight inhibitory effect on the seedlings and roots of L. sativum, and at the dilution of 1 : 1000 stimulated growth by 30 %. Insignificant changes in the mitotic index of the meristem of A. cepa roots were revealed at the effect of the culture fluid of P. melonis, strain 502, diluted at the ratio of 1 : 100 and 1 : 1000. At the same time, the number of cells at the prophase stage decreased 1.7 times (1 : 100 dilution). There is a significant increase in the number of cells at the metaphase stage – 1.3 and 1.4 times (dilution 1 : 100 and 1 : 1000, respectively), the anaphase stage – 2.1 and 1.8 times (dilution 1 : 100 and 1 : 1000, respectively) and the telophase stage – 1.8 times (1 : 100 dilution), as compared with the positive control (culture medium). The frequencies of aberrant ana-telophases in the apical meristems of the initial roots were 5.0 and 2.2 % (at the culture fluid dilution of 1 : 100 and 1 : 1000, respectively). We researched the abil- ity of P. melonis 502 to synthesize ethylene and the highest level of it was registered after 5 weeks of cultivation (111.78 nmol/h g). Conclusions: It was demonstrated by us that the culture fluid of strain 502 showed no phytotoxic effect on roots and seedlings of the investigated cultures, demonstrating the exclusion of phytotoxins from the possible range of effectors. No cytotoxic or genotoxic activity of the culture fluid was observed either. However, the culture fluid altered the dynamics of the cell cycle, in particular, shortened the prophase and stimulated the metaphase, anaphase, and telophase. The culture fluid of the fungus stimulated the growth of L. sativum roots depending on the nutrient medium, where the fungus was grown and cultivated. In particular, when growing the fungus on the liquid wort, the growth was higher by 54 and 41 % (dilution 1 : 10 and 1 : 100, respectively), when growing on synthetic Raulin-Thom’s medium – by 30 %. This demonstrates the ability of strain 502 to possibly synthesize growth promoting substances. Also, we have shown the ability of this strain to synthetize ethylene in vitro (111.78 ± 13.27 nmol/h per g), which can act as virulence factor. We consider the obtained results to be the first stage of the study on the mechanism of the interaction between pathogenic strain 502 and plants.

A systematic invesitgation of ester and ether derivatives of 3,7-dimethyl-8-hydroxy-6-methoxyisochroman and 3,7-dimethyl-6-hydroxy-8-methoxyisochroman has established that all of the derivatives synthesized exhibited activity in the wheat coleoptile assay, with several of the compounds being more active than the parent systems. Keywords: Esters and ethers of isochroman; plant growth regulatory activity

In this study, bacteria were isolated from the rhizosphere and inside the roots and nodules of berseem clover plants grown in the field in Iran. Two hundred isolates were obtained from the rhizosphere (120 isolates), interior roots (57 isolates), and nodules (23 isolates) of clover plants grown in rotation with rice plants. Production of chitinase, pectinase, cellulase, siderophore, salicylic acid, hydrogen cyanide, indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase, solubilization of phosphate, antifungal activity against various rice plant pathogen fungi, N2 fixation, and colonization assay on rice seedlings by these strains was evaluated and compared (endophytic isolates vs. rhizosphere bacteria). The results showed both the number and the ability of plant growth-promoting (PGP) traits were different between endophytic and rhizosphere isolates. A higher percentage of endophytic isolates were positive for production of IAA, ACC deaminase, and siderophore than rhizosphere isolates. Therefore, it is suggested that clover plant may shape its own associated microbial community and act as filters for endophyte communities, and rhizosphere isolates with different (PGP) traits. We also studied the PGP effect of the most promising endophytic and rhizosphere isolates on rice seedlings. A significant relationship among IAA and ACC deaminase production, the size of root colonization, and plant growth (root elongation) in comparison with siderophore production and phosphate solubilization for the isolates was observed. The best bacterial isolates (one endophytic isolate and one rhizosphere isolate), based on their ability to promote rice growth and colonize rice roots, were identified. Based on 16S rDNA sequence analysis, the endophytic isolate CEN7 and the rhizosphere isolate CEN8 were closely related to Pseudomonas putida and Pseudomonas fluorescens, respectively. It seems that PGP trait production (such as IAA, ACC deaminase) may be required for endophytic and rhizosphere competence as compared to other PGP traits in rice seedlings under constant flooded conditions. The study also shows that the presence of diverse rhizobacteria with effective growth-promoting traits associated with clover plants may be used for sustainable crop management under field conditions.

A method for the synthesis of esters of 2-(dimethylsulfonium)ethylphos-phonic acid and the results of some trials showing the plant growth regulating activity of these compounds are presented. For the synthesis of the mentioned compounds, dimethyl sulphide is reacted with 2-chloroethylphosphonic acid esters; these esters are obtained through the complex[1] of AlCl3, PCl3 and 1,2-dichloroethan (1). Using the optimum reaction conditions, very good yields were obtained (96–99%). This complex is reacted with different alcohols to give 2-chloroethylphosphonic acid esters (2) (R˭Me, Et, Pr, i-Pr, Bu, i-Bu, Pe). Using the optimum reaction conditions, in the case of methanol the maximum obtained yield was 50%. In the case of the other alcohols, the obtained yields were between 76 and 83%. An exception is i-propanol. whose ester was obtained with low yields and the reaction parameters modification have little influence on the yield. The reaction of the esters with dimethyl sulphide gives, in good yields (between 69 and 79%). esters of 2-(dimethylsulfonium)ethylphosphonic acid (3). substances with plant growth regulating activity.