Fusarium Disease of Maize and Its Management through Sustainable Approach

Fusarium causing disease in maize is probably the one of the most serious diseases among the crop plants all over the world. It not only damages the maize plant, reduces its potential yield and its nutritional values but imposes threatening to the human life through the induction of mycotoxin development. F. graminearum and F. moniliforme syn. Fusarium verticillioides are two important maize pathogens that cause substantial damage to its ear, stalk and foliage, causing contamination of grains with mycotoxins. Since conventional methods of controlling the diseases including the chemical methods proved not enough for total control of the disease with creating situation even worse for our surroundings, the application of PGPR and PGPF can play significant role to control the damage caused by Fusarium

Reactivity of some cuprous salts towards tenmembered macrocyclic disulphides: a new route to the synthesis of Cu(II)-thiolates

Cuprous ion is found to be quite reactive towards disulphide present in a macrocycle. Thus, when [Cu(MeCN)4] BF4 or [Cu(MeCN)4]ClO4 is allowed to reflux in acetonitrile with a ten-membered macrocycle containing two amino nitrogens and one disulphide donor in an atmosphere of nitrogen, electron transfer takes place from the metal centre to the disulphide group. As a result, copper is oxidised to the +2 state and the disulphide reduced to thiolates. The thiolates then bind the Cu(II) and form discrete and neutral CuN2S2 complexes. Syntheses of two new CuN2 S2 complexes have been achieved following this route. The reactions take place smoothly and give the desired product in excess of 25% yield with respect to the macrocycle. Electronic absorption spectral results are consistent with a nearly square planar geometry. Each of the two complexes isolated exhibits quasireversible Cu(II)/Cu(I) couple with Ef near - 0.3 V vs SCE. Both the complexes are further characterised by room temperature magnetic susceptibility, EPR spectroscopy at 298 and 77 K and elemental analyses

Sensory cutaneous nerve fine-needle aspiration in Hansen′s disease: A retrospective analysis of our experience

Background: Leprosy affects peripheral nerves. As Mycobacterium leprae has unique tropism for Schwann cells, thickened sensory cutaneous nerves provide an easy target for the detection of lepra bacilli and other changes associated with the disease. Materials and Methods: The data of patients with sensory cutaneous nerve involvement were retrieved from our record for the period January 2006 to December 2014. The hematoxylin and eosin (H and E)- and May-Grünwald-Giemsa (MGG)-stained slides were screened for Schwann cells, granuloma, and necrosis. Modified Ziehl-Neelsen (ZN)-stained smears were searched for lepra bacilli and globi. Morphological index was calculated in multibacillary lesions. Result: Twenty-nine sensory cutaneous nerves were aspirated in 23 patients. While 15 cases showed skin and nerve involvement, 8 cases showed only nerve involvement. Terminal cutaneous branch of the radial nerve was most often aspirated. No motor loss was observed after aspiration. Five cytologic pictures were seen - Epithelioid cell granuloma only in 6 cases, epithelioid cell granuloma with necrosis in 1 case, epithelioid cell granuloma with lepra bacilli in 3 cases, necrosis with lepra bacilli in 1 case, and only lepra bacilli in 12 cases. Morphological index ranged from 20% to 80%. Conclusion: Sensory cutaneous nerve fine-needle aspiration (FNA) is a feasible, viable, effective, and safe procedure. It adds to diagnostic FNA yield in patients with concomitant skin involvement and offers a way to evaluate patients with only nerve involvement. Calculation of morphological index allows prognostication and may have a role in assessing response to therapy and/or relapse

Modelling the blue protein active sites: synthesis and characterization of CuN<SUB>2</SUB>S<SUB>2</SUB> complexes showing rhombic EPR spectra and high Cu<SUP>II</SUP>/Cu<SUP>I</SUP> potential

Two new tetradentate ligands have been synthesized by Schiff base condensation oof diisobutyraldehyde disulphide with 2-mercaptoethylamine (L1) and 2-aminothiophenol (L2) respectively and then reducing the imine linkages with NaBH4 in refluxing methanol. In the free ligands the thiolate sulphur is protected with tertiary butyl groups which are cleaved in the presence of CuII-salts to give neutral CuN2S2 complexes. The copper complexes show ligand field transitions at 815 and 760 nm at room temperature which are independent of the solvents used and are consistent with a pseudotetrahedral coordination around the CuII ion. The EPR spectrum of the aliphatic thiolate in MeCN glass shows significant rhombic splitting (gx−gx = 0.09 and Ax−Ay = 60 × 10−4 cm−1) attributable to δ z2 mixing into the ground state wavefunction. For the aromatic thiolate complex, however, the EPR spectrum was not well resolved although the rhombic nature of the spectrum could easily be observed. Both the complexes exhibit well-defined cyclic responses in their cyclic voltammograms at RT and in acetonitrile for the CuII/CuI couple with E½ =0.5V vs SCE. This high positive value for the redox couple is also consistent with a coordination geomttry much distorted from planarity. The active sites of the blue protein which contain copper in distorted geomtries exhibit CuII/CuI potential in the range 300-800 mV vs NHE at pH = 7.0

Electrochemical studies of some nickel(ll) complexes of the type [Ni(N - N - S)(CN)] and [Ni2(N - N - S)2-µ-(CN)] (CIPO4): Generation of nickel (I) species

335-338The electron transfer behaviour of Ni(II) complexes [NiL(CN)](L= L1-L3) and [Ni2L-µ-(CN)](CIO4) (where HL1 = methyl 2-[(2'-aminoethyl)amino]cyclopent-l-enedithiocarboxylate, HL2 = methyl 2-[(2'-dimethylaminoethyl)amino]cyclopent-l-enedithiocarboxylate, HL3 =methyl 2-[(2'-diethylaminoethyl)amino]cyclopent-l-enedithiocarboxylate) has been investigated by cyclic voltammetric measurements in acetonitrile. In the potential range of 0 to - 2 V all the mononuclear complexes undergo metalcentred quasi-reversible one-electron reduction and the E1/2 values (ca. - 1.57 V vs SCE) remain almost unchanged with the variation of L. For the dinuclear complex two-step one-electron transfer occurs and the corresponding redox potentials are - 0.96 and - 1.61 V (vs SCE). The conproportionation constant for the mixed-valence species has been estimated to be 1011

Ni(II), Cu(II), and Zn(II) cryptate-enhanced fluorescence of a trianthrylcryptand: a potential molecular photonic OR operator

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Synthesis and studies of Cu(II)-thiolato complexes: bioinorganic perspectives

Ligation of thiolate sulfur to copper at the active sites of quite a number of copper proteins has been established either by X-ray crystallographic and/or by spectroscopic studies. In addition, for Cu(II)-substituted metalloproteins, the presence of Cu(II)-thiolate bonding at the active sites could be established spectroscopically. Cu(II)-thiolate bonding in different enzymes is not always very similar. Obviously, the bioinorganic significance of Cu(II)-thiolate bonding is enormous and has attracted a lot of attention to synthesize model Cu(II)-thiolato complexes as electronic structural analogues of the active sites of these biomolecules. The present review deals with (i) nature of Cu(II)-thiolate bonding present in different metalloproteins, (ii) difficulties involved in the synthesis of Cu(II)-thiolates and ways to surmount them, (iii) characterization of the Cu(II)-thiolate bonding by electronic and EPR spectroscopic techniques and (iv) electron transfer properties of the Cu(II)-thiolato complexes by cyclic voltammetric studies. The properties of the Cu(II)-thiolato complexes have been discussed as possible models for the active site(s) of copper proteins

Simulation of leaf curl disease dynamics in chili for strategic management options

Abstract Leaf curl, a whitefly-borne begomovirus disease, is the cause of frequent epidemic in chili. In the present study, transmission parameters involved in tripartite interaction are estimated to simulate disease dynamics in a population dynamics model framework. Epidemic is characterized by a rapid conversion rate of healthy host population into infectious type. Infection rate as basic reproduction number, R 0 = 13.54, has indicated a high rate of virus transmission. Equilibrium population of infectious host and viruliferous vector are observed to be sensitive to the immigration parameter. A small increase in immigration rate of viruliferous vector increased the population of both infectious host and viruliferous vector. Migrant viruliferous vectors, acquisition, and transmission rates as major parameters in the model indicate leaf curl epidemic is predominantly a vector -mediated process. Based on underlying principles of temperature influence on vector population abundance and transmission parameters, spatio-temporal pattern of disease risk predicted is noted to correspond with leaf curl distribution pattern in India. Temperature in the range of 15–35 °C plays an important role in epidemic as both vector population and virus transmission are influenced by temperature. Assessment of leaf curl dynamics would be a useful guide to crop planning and evolution of efficient management strategies

A hexadentate nickel(II) complex with a tripodal ligand bearing S<SUB>3</SUB>N<SUB>3</SUB> donors: synthesis, spectroscopic and X-ray crystal structural investigation

A tripodal ligand, tris[2-(2-aminoethyl)thio]ethane (L<SUP>1</SUP>), bearing three thioether sulphurs and three primary amino nitrogens has been synthesized in high yield. Reaction with nickel(II) perchlorate hexahydrate yielded the complex [Ni(L<SUP>1</SUP>)](ClO)<SUB>4</SUB>, which has been characterized by X-ray crystallography. The structure consists of two independent hexacoordinate cage cations and four independent perchlorate anions. The Ni<SUP>II</SUP>ion is bound equatorially to two nitrogen and two sulphur atoms, while the other two donor atoms occupy the acial positions. Both the independent cage cations are disordered, with thioether sulphurs occupying two alternative sets of ligand sites. One of the four perchlorate anions is also disordered. IR, conductivity, RT magnetic susceptibility and electronic absorption spectral data are consistent with the solid state structure. The corresponding aromatic analogue, tris[2-(2-aminophenyl)thio]ethane (L<SUP>2</SUP>), forms the complex [Ni(L<SUP>2</SUP>)](ClO<SUB>4</SUB>)<SUB>2</SUB>, which has been characterized spectroscopically

Syntheses and X-ray structures of mixed-ligand salicylaldehyde complexes of Mn(III), Fe(III), and Cu(II) ions: reactivity of the Mn(III) complex toward primary monoamines and catalytic epoxidation of olefins by the Cu(II) complex

The Schiff base (L), synthesized from 2-(dimethylamino)ethylamine and salicylaldehyde acts as a tridentate ligand. This ligand, when stirred with 1 equiv of KOH in methanol, undergoes partial hydrolysis of the imine bond. This solution readily takes up Mn(II)/Mn(III) acetate or Fe(III) chloride/perchlorate to form mixed-ligand Mn(III) or Fe(III) complexes, respectively. The neutral dark brown complex, [Mn(L-H)(NCS){o-(CHO)C6H4O-}] (1), crystallizes in the presence of thiocyanate in the orthorhombic space group Pbca with a = 15.271(8), b = 19.522(7), c = 13.213(7) &#197; Z = 8; R = 0.060; and Rw = 0.062. The coordination geometry around Mn(III) ion is distorted octahedral with donation from one L-H, one salicylaldehyde and, one thiocyanate ligand. With Fe(III), the dark red complex isolated in the solid state is found to be a neutral &#181;-oxo Fe(III) dimer with the formula [{o-(CHO)C6H4O-}(L-H)Fe]2O (3). The structure of 3 has been solved and successfully refined in the monoclinic space group C2/c with a = 18.558(7), b = 11.231(5), c = 16.943(6) &#197;; &#946; = 95.81(3)&#176;; Z = 4; R = 0.052; and Rw = 0.055. Each of the Fe(III) ions is hexadentate with donation from one L-H and one salicylaldehyde besides the bridged O atom. The Fe(III)-O-Fe(III) angle is found to be 166.05(4)&#176;, which is well within the normal range observed for monobridged Fe(III)-O-Fe(III) complexes. Due to structural trans effects, the coordination geometry around each metal center is distorted from the ideal octahedral geometry. Cu(II) makes the neutral complex, [Cu(L-H){o-(CHO)C6H4O-}] (2) when L, salicylaldehyde, and a Cu(II) salt are allowed to react in equimolar quantities in the presence of excess of KOH. It crystallizes in the monoclinic space group C2/c with a = 18.077(4), b = 11.514(2), c = 16.716(4) &#197;; &#946; = 93.66(2)&#176;; Z = 8; R = 0.057; and Rw = 0.061. The coordination geometry around Cu(II) is square pyramidal where, out of the four equatorial donors, three are provided by the Schiff base L and the fourth one by the phenolate O of the salicylaldehyde group. The Cu(II) ion is 0.170(5) &#197; above the equatorial plane and is bonded axially to the O atom of the carbonyl group of the salicylaldehyde. The bound salicylaldehyde in the Mn(III) complex 1 readily reacts with the reagents 2-aminophenol, 2-aminothiophenol, or 2-aminoethanol to form mononuclear, neutral Mn(III) complexes 4-6, respectively, with the general formula,[Mn(L-H)(L'-2H)]. The Schiff base L' is formed by condensation of the bound salicylaldehyde in 1 with the amino group of the added reagent. Complex 4 is low-spin (&#956;eff/&#956;B = 3.01; S = 1) at 300 K, which is quite rare. It also exhibits a pseudoreversible Mn(IV)/Mn(III) couple with E&#189; = 0.54 V (vs SCE) in DMF. All the other Mn complexes are high-spin (&#181; eff/&#181; B range, 4.89-4.94; S = 2) at 300 K. The &#956;eff/&#956;B number for 2 is 1.93 and for 3 is 1.84. Complex 2 shows catalytic activity in the oxidation of olefins to epoxides in the presence of 2-methylpropanal and molecular oxygen