Investigation on the Biocontrol of Phytophthora diseases on strawberry based on antagonism

After screening of several rhizosphere bacteria against the soilborne pathogens of red core and crown rot disease of strawberry Phytophthora fragariae var. fragariae and Phytophthora cactorum under in vitro conditions, three of the most active isolates which produced up to 63% of reduction in mycelium growth, such as Raoultella terrigena (G-584), Bacillus amyloliquefaciens (G-V1) and Pseudomonas fluorescens (2R1-7) were selected for further studies under in vivo conditions. In a greenhouse and field experiments, mentioned above three isolates were tested against both Phytophthora diseases under artificial infested soil conditions. Root dip treatment with these bacterial antagonists produced a control effect on both fungal diseases between 27 to 55 % and were in some cases comparable with the chemical fungicide Aliette

Effect of alkaline treatment on the sulfate content and quality of semi-refined carrageenan prepared from seaweed Kappaphycus alvarezii Doty (Doty) farmed in Indian waters

Seaweed Kappaphycus alvarezii previously known as Eucheuma cottonii is one of the best sources of kappa carrageenan and is cultivated in Philippines, Indonesia, Malaysia and other countries including India. In the present study, semi-refined carrageenan (SRC) was prepared from K. alvarezii with different concentrations of KOH (6, 12, 18 and 24%) at 80 ± 2°C for 2 h; its sulfate contents were 13.73±0.74, 13.66±0.27, 13.84±0.66 and 14.76±0.18%, respectively, and it was 14.10±0.34% for untreated clean weed (control). The sulfate removal with increasing concentration of KOH used for processing SRC is not statistically significant (p < 0.05). The KCl gel strength of untreated clean weed and 6, 12, 18 and 24% KOH treated weed was 97±10.27, 650±12.11, 637±10.25, 552±18.71 and 526±26.55 g cm-2, respectively. Contents of 3,6-anhydrogalactose were 28.30±0.52, 33.41±0.50, 32.97±0.42, 31.15±0.60 and 31.61±0.17%. FTIR spectroscopy showed that molecules in all four SRC samples are quite similar. Spectral band was at 1257 cm-1 which referred to ester sulfate of 930 cm-1 for 3,6 anhydrogalactose and 848 cm-1 assigned to galactose-4-sulfate. From the present investigation, it was observed that sulfate removal and quality improvement with increasing concentration of KOH for cooking seaweed is not statistically significant; therefore, seaweed can be subjected to lower concentration of KOH treatment (6 to 12%) to produce semi-refined carrageenan on commercial scale.Keywords:  Seaweed, Kappaphycus alvarezii, KOH treatment, semi-refined carrageenan (SRC), sulfate content, FTIR spectra, gel strength.Abbreviation: SRC, semi-refined carrageenan; 3,6-AG, 3,6-anhydrogalacotse; FTIR, Fourier Transform Infrared Spectroscopy

Computational modelling of meiotic entry and commitment

In response to developmental and environmental conditions, cells exit the mitotic cell cycle and enter the meiosis program to generate haploid gametes from diploid germ cells. Once cells decide to enter the meiosis program they become irreversibly committed to the completion of meiosis irrespective of the presence of cue signals. How meiotic entry and commitment occur due to the dynamics of the regulatory network is not well understood. Therefore, we constructed a mathematical model of the regulatory network that controls the transition from mitosis to meiosis in Schizosaccharomyces pombe. Upon nitrogen starvation, yeast cells exit mitosis and undergo conjugation and meiotic entry. The model includes the regulation of Mei2, an RNA binding protein required for conjugation and meiotic entry, by multiple feedback loops involving Pat1, a kinase that keeps cells in mitosis, and Ste11, a transcription activator required for the sexual differentiation. The model accounts for various experimental observations and demonstrates that the activation of Mei2 is bistable, which ensures the irreversible commitment to meiosis. Further, we show by integrating the meiosis-specific regulation with a cell cycle model, the dynamics of cell cycle exit, G1 arrest and entry into meiosis under nitrogen starvation. © 2017 The Author(s)

Investigation on the biocontrol of Phytophthora diseases on strawberry based on antagonism

After screening of several rhizosphere bacteria against the soilborne pathogens of red core and crown rot disease of strawberry Phytophthora fragariae var. fragariae and Phytophthora cactorum under in vitro conditions; three of the most active isolates which produced up to 63 % of reduction in mycelium growth, such as Raoultelfa terrigena (G-584), Bacillus amyloliquefaciens (G-V1) and Pseudomonas fluorescens (2R1-7) were selected fcir further studies under-in vivo conditions. In a greenhouse and field experiments, mentioned above three isolates were tested against both Phytophthora diseases under artificial infested soil conditions. Root dip treatment with these bacterial antagonists produced a control effect on both fungal diseases between 27 to 55% and were in some cases comparable with the chemical fungicide Aliette

Untersuchungen zur biologischen Bekämpfung der Roten Wurzelfäule und Rhizomfäule der Erdbeere (Phytophthora fragariae var. fragariae und P. cactorum) mit Rhizosphärebakterien

After in vitro screening of more than 100 bacterial isolates from the rhizosphere on their antagonistic effect against Phytophthora fragariae var. fragariae and P. cactorum, the two causal agents of red stele and crown rot disease of strawberry, three bacteria out of different genera Raoultella terrigena (G-584), Bacillus amyloliquefaciens (G-V1) and Pseudomonas fluorescens (2R1-7) were found with the highest inhibitory effect on the mycelial growth of both Phytophthora spp. For the management of both fungal diseases the antagonistic bacteria were further evaluated under greenhouse and field conditions. In greenhouse all three bacteria were significantly effective in reducing red core and crown rot, exhibited a similar level of control as the chemical fungicide Aliette of up to 59%. In field trials conducted at different locations in Germany under artificially and naturally infested soil conditions in two season 2003 to 2005, different level of biocontrol was performed by the tested bacteria. In trial of the first season under artificial conditions, the three rizhobacteria showed a significant control up to 45% against both diseases and in the next season, only B. amyloliquefaciens was effective against red stele. Under natural conditions, significant effect of 37.5% was observed from a mixture of R. terrigena and B. amyloliquefaciens in first season and in second season R. terrigena showed significant effect of 45.1% in the northern part of Germany. In the south, R. terrigena and B. amyloliquefaciens were significantly efficient up to 51.5% and the overall effect were similar to Aliette

Unusual seedless approach to gold nanoparticle synthesis: application to selective rapid naked eye detection of mercury(II)

Report a novel seedless Hg2+-induced synthetic approach for the preparation of gold nanostructures. This protocol is demonstrated for the highly selective and sensitive naked eye detection of Hg2+ based on the high affinity metallophilic Hg2+–Au+ interaction. The response time upon exposure to Hg2+ is almost instantaneou

SWOT analysis of the electrochemical reactivity of different carbon paste electrodes

275-282<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" te"="" lang="EN-GB">The electroactivity of different carbonaceous materials suitable for electroanalytical applications has been described. Voltammetric studies reveal that only Vulcan carbon and single walled carbon nanotube show well defined voltammetric behavior with clear peak-to-peak separation close to the Nernstian behavior. Acetylene and activated carbon does not show the expected electroactivity and the reason is discussed with the help of electrochemical impedance analysis. The varied performances in terms of structure and morphology of different carbonaceous materials are further characterized using Raman spectroscopy, contact angle measurement, scanning electron microscope and thermo gravimetric analysis.</span