Ovipositional preference and larval performance of poplar defoliator,Clostera restitura on different poplar clones in north-western India

We evaluated ten poplar clones (G-3, G-48, L-50/88, L-154/84, L-156/89, S7C8, S7C15,WSL-22, WSL-29 and Uday) for ovipositional preference and larval performance of Clostera restitura. Female moths did not show any preference with respect to clones for oviposition. Significant differences were observed for number of eggs laidon different plant parts. C. restitura laid eggs in clusters, preferably onupper surface of leaf and size of the egg cluster varied from 15 to 167eggs. Clones varied for their relative resistance and susceptibility to C.restitura. L-50/88; L-156/89 were identified as most resistant clone basedon minimum leaf consumption, whereas S7C15 was found to be most susceptible clone to C. restitura. In multiple choice experiments, no feeding preference by C. restitura larvae was detected amongst different poplar clones. After initial settlement of larvae on a particular clone, thelarvae remained confined to that clone and negligible inter-clonal movement was noticed subsequently. The fresh pupal weight was correlated negatively (r = 0.37) with percentage surface leaf area eaten and positively (r = 0.47) with length of larval period, measured on different clones. Relationship between percentage leaf area eaten and length of larval period was negative (r = 0.23). Owing to relative resistance of L-50/88 and L-156/89 against C. restitura, these clones can be recommended for plantation in defoliator prone areas in north-western India.

Microstructural analysis and hot corrosion behavior of HVOF-sprayed Ni–22Cr–10Al–1Y and Ni–22Cr–10Al–1Y–SiC(N) coatings on ASTM-SA213-T22 steel

The present paper deals with the investigation of microstructure and high-temperature hot corrosion behavior of high-velocity oxy fuel(HVOF)-produced coatings. Two powder coating compositions, namely, Ni22Cr10Al1Y alloy powder and Ni22Cr10Al1Y(80 wt%;microsized)–silicon carbide(SiC)(20 wt%;nano(N)) powder, were deposited on a T-22 boiler tube steel. The hot corrosion behavior of bare and coated steels was tested at 900°C for 50 cycles in Na2SO4–60 wt%V2O5 molten-salt environment. The kinetics of corrosion was established with weight change measurements after each cycle. The microporosity and microhardness of the as-coated samples have been reported. The X-ray diffraction,field emission-scanning electron microscopy/energy dispersive spectroscopy, and X-ray mapping characterization techniques have been utilized for structural analysis of the as-coated and hot-corroded samples. The results showed that both coatings were deposited with a porosity less than2%. Both coated samples revealed the development of harder surfaces than the substrate. During hot corrosion testing, the bare T22 steel showed an accelerated corrosion in comparison with its coated counterparts. The HVOF-sprayed coatings were befitted effectively by maintaining their adherence during testing. The Ni22Cr10Al1Y–20 wt%SiC(N) composite coating was more effective than the Ni–22Cr–10Al–1Y coating against corrosion in the high-temperature fluxing process.

Persistence of Indoxacarb on Cauliflower (<i>Brassica oleracea var. botrytis.</i>L.) and Its Risk Assessment

A rapid, simple and an efficient method for the determination of indoxacarb in cauliflower and soil samples was developed and validated using QuEChERS technique (Quick, Easy, Cheap, Effective, Rugged and Safe). Recoveries at four different spiking concentrations of 0.01, 0.05, 0.1 and 0.2 mg kg–1 ranged from 87 to 96% were achieved with good repeatability and RSD of 1% - 6%. The average initial deposits of 0.23 and 0.45 mg kg–1 were observed after last application of indoxacarb @ 52.2 and 104.4 g. a.i. ha–1 at recommended and double the recommended dosages, respectively. The residues in cauliflower dissipated below its LOQ of 0.01 mg kg–1 after 7 days and its half-life periods were observed to be 1.12 and 1.31 days, respectively, at single and double the dosages. Keeping in view 80 g consumption of cauliflower curds per day for a 55 kg person, theoretical maximum residue contribution (TMRC) of indoxacarb when calculated from maximum residues observed on 0 day samples at recommended and double the recommended dosages, respectively, were found to be 20.8 and 36.8 μg in comparison to its acceptable daily intake (ADI) of 550 μg, which is quite safe.