Effects of Striga gesnerioides on the Growth and Yield of Some Cowpea (Vigna unguiculata (L.) Walp) Genotypes under Water Stress Condition

Cowpea production in the Sahelian region faced production constraint due to disease and drought. Striga gesnerioides is a major constraint to cowpea production specifically to the agronomic point of view. The aim of this present study is to determine the effect of Striga gesnerioides on the growth and yield of some cowpea genotypes subjected to different moisture stress conditions. The experiment was conducted at screen house of the International Institute of Tropical Agriculture (IITA) Kano, Nigeria. Three cowpea varieties were used in the experiment, the experimental set up was completely randomized design with four treatment regimes; T1, vegetative stage of water stress with Striga infestation; T2, vegetative stage of water stress; T3, unstressed with Striga infestation and T4, unstressed. Uniform broadcasting of 0.05g of Striga gesnerioides were imposed in the treatment. Data were collected on plant height, number of leaves, plant vigor score, phenology, and grain yield. The results showed that there is a significant difference in the number of leaves between the treatments with DANILA having the highest number of leaves. DANILA was found to exhibit the highest plant vigor. Total chlorophyll reductions were recorded at 37 days after water stress and striga infestation.DANILA recorded the highest reduction in total chlorophyll content. The results showed that IT98K-205-8 matured earlier and recorded higher yield, Danilarecorded low yield. It can be concluded that cowpea varieties IT97K-499-35 and IT98K-205-8 which gave the highest yield were resistance to Striga gesnerioides, whereas Danila which developed Symptoms with reduced yield is said to be susceptible to Striga gesnerioides.Keyword: Striga gesnerioides, cowpea, water stres

Quantized Orbits and Resonant Transport

A tight binding representation of the kicked Harper model is used to obtain an integrable semiclassical Hamiltonian consisting of degenerate "quantized" orbits. New orbits appear when renormalized Harper parameters cross integer multiples of $\pi/2$. Commensurability relations between the orbit frequencies are shown to correlate with the emergence of accelerator modes in the classical phase space of the original kicked problem. The signature of this resonant transport is seen in both classical and quantum behavior. An important feature of our analysis is the emergence of a natural scaling relating classical and quantum couplings which is necessary for establishing correspondence.Comment: REVTEX document - 8 pages + 3 postscript figures. Submitted to Phys.Rev.Let

Fine structure of K\mathrm{K}-excitons in multilayers of transition metal dichalcogenides

Reflectance and magneto-reflectance experiments together with theoretical modelling based on the $\mathbf{k\cdot p}$ approach have been employed to study the evolution of direct bandgap excitons in MoS$_2$ layers with a thickness ranging from mono- to trilayer. The extra excitonic resonances observed in MoS$_2$ multilayers emerge as a result of the hybridization of Bloch states of each sub-layer due to the interlayer coupling. The properties of such excitons in bi- and trilayers are classified by the symmetry of corresponding crystals. The inter- and intralayer character of the reported excitonic resonances is fingerprinted with the magneto-optical measurements: the excitonic $g$-factors of opposite sign and of different amplitude are revealed for these two types of resonances. The parameters describing the strength of the spin-orbit interaction are estimated for bi- and trilayer MoS$_2$.Comment: 14 pages, 10 figure

Modeling and Simulation of CNT Using VNL

Modeling and simulation of metallic are performed through ATK and VNL by quantum wise. The simulation results for the voltage current of length of 17.32 shows more conduction if the length is 21.92 the simulation results for the current voltage shows less conduction

Bis(μ-phenyl­tellurido-κ2 Te:Te)bis­[tetra­carbonyl­rhenium(I)]

The title compound, [Re2(C6H5Te)2(CO)8], crystallizes with two mol­ecules in the asymmetric unit, in which two Re atoms are coordinated in a slightly distorted octa­hedral environment and are bridged by two Te atoms, which show a distorted trigonal-pyramidal geometry. The torsion angles for the Te—Re—Te—Re sequence of atoms are 19.29 (18) and 16.54 (16)° in the two mol­ecules. Thus, the Re—Te four-membered rings in the two mol­ecules deviate significantly from planarity. Two intra­molecular C—H⋯O inter­actions occur in one of the mol­ecules. Te—Te [4.0551 (10) Å] inter­actions between the two mol­ecules and weak inter­molecular C—H⋯O inter­actions stabilize the crystal packing

Isolation and characterisation of microorganisms contaminating herbal infusion sold in Minna, Nigeria

The microbiological assessment of ten herbal infusion samples from ten different locations in Minna, Niger State was investigated. The assessment of the microbial contamination on the herbal products was carried out, using standard methods. Pour plate method was used to cultivate serially diluted portions of the medicinal plant infusion samples. The results revealed that all the herbal preparations had the presence of microbial contaminants. The total heterotrophic counts of the different herbal samples ranged from 0 cfu/mL to 25.0 × 108cfu/mL while the total fungal counts ranged from 3.0×106cfu/mL to 3.5×108cfu/mL. The total viable bacteria counts showed that the highest counts of 25.0 × 108cfu/mL was recorded in the sample from Bosso and the least counts of 0 cfu/mL from Kasuwan-Gwari while the total fungal counts showed that the highest count of 3.5×108cfu/mL was found in the sample obtained from FUT campus and the least counts of 3.0×106cfu/mL in the sample from Mai-Kunkele. One way analysis of variance (ANOVA) showed that there was significant difference (p<0.05) in the microbial load of the herbal infusions from each location. The microbial isolates identified were E. coli, Staphylococcus aureus, Shigella sp, Klebsiella sp, Pseudomonas sp, Micrococcus sp, Salmonella sp, Aspergillus sp, Penicillium sp and Saccharomyces cerevisaie. Members of the genus Aspergillus were found to be predominant. This suggests that the herbal infusion harbors microorganisms that could be hazardous to human health and hence producers should maintain the highest possible level of hygiene during the processing and packaging of the products in order to ensure safety of the products