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Almost one-fourth of India's oilseed production is contributed by Brassicas. The Indian mustard [ Brassica juncea ] crop is affected by several biotic stresses in India, including aphid, white rust, Alternaria blight and Sclerotinia rot, which affect crop yields. Field trials were conducted at three locations during three crop seasons (2013–16) to evaluate treatments appropriate for mitigation of crop stresses and to obtain accurate assessments for seed yields and economic benefits as a part of a prioritized component-wise Integrated Pest Management strategy for the oilseed Brassica crop. The records from diverse sites and seasons concerning infestations by biotic stresses were assembled and scrutinized. The highest reduction in the severity of white rust disease was observed due to seed treatment by metalaxyl M 31.8 ES @ 6 ml/kg seed in one experiment and by a foliar spray of a combination of mancozeb 68% + metalaxyl 4% @ 1.7 g a.i./l in another trial, the latter being economically inferior to other fungitoxicants. The highest incremental benefit cost ratio (IBCR) was noted with the treatment of seed by an aqueous extract of garlic bulb (2% w/v) in one trial and by application of Trichoderma harzianum @ 1 g/l in another trial over sprays on crop foliage over two years and over three levels of nitrogen. Thiamethoxam 25 WG @ 1 g a.i./10 l ranked better than all other spray treatments in decreasing population of aphid in the top 10 cm main shoot at two sites. Pre-sowing application of T. harzianum @ 2.5 kg/ha soil provided better mustard seed yield in combination with spray with thiamethoxam 25 WG @ 1 g a.i./10 l on crop foliage and treatment of seed with T. harzianum @ 10 g/kg seed. Though the seed yield of mustard crop was the best with the integration of applications of T. harzianum on seed, to the soil along with spray of thiamethoxam 25 WG @ 1 g a.i./10 l on crop foliage at 50 days after sowing, it did not give the highest IBCR (16.6) among treatments. Contrastingly, treatment of seed with T. harzianum alone gave the highest IBCR (112.6), where the seed yield was relatively much lower (1469 kg/ha) whilst treatment of seed with fresh aqueous extract of garlic bulb @ 2% w/v also provided a high (80.4) IBCR. This paper highlights the impact of input costs, which allows growers to decide inputs based on the prevalence of biotic stress(es), the decision on intervention based on the importance of the same with an idea about the resultant quantifiable and monetary impact. • Impact of input costs. • Helps decide inputs based on prevalence of biotic stress(es) with quantifiable impact. [ABSTRACT FROM AUTHOR]

In the current article, the influence of four different cw-lasers on the thermally activated a c. conduction of a novel quaternary chalcogenide glassy semiconductor Se 72 Te 20 Sn 2 Cd 6 has been reported at different audio frequencies. We have used four different laser sources of wavelengths lying in UV–Vis-IR region. The variation of a c. conductivity with temperature obeys the Arrhenius relation for all the four laser light sources. Further analysis confirms that pre-exponential factor of thermally governed a c. conduction and the activated energy involved in the phenomenon follows MNCR. It is also found that this correlation remains independent of laser wavelength. [ABSTRACT FROM AUTHOR]

Structure and its transformation are examined for amorphous Se-rich As x Se 1-x (0 ≤ x ≤ 0.2) alloys by employment of diffraction and non-diffraction structural probes. It is shown that the molecular structure of amorphous Se (a-Se) on the scale of short-range order is close to that of crystalline phase, while medium-range order differs from the structure of most inorganic glasses and may be placed between three-dimensional network glasses and polymeric ones. Further experiments show the existence of successive phases in laser-induced glass-crystalline transition with pronounced threshold behavior. Below the energy density threshold, E th , only small changes in the local structure of the system can be detected. Above E th , the changes were attributed to crystallization transformation. The corresponding Raman spectra reveal transformation of the system from amorphous into the crystalline phase under laser irradiation. In the binary As x Se 1-x glass system, a change of structural regime takes place near the composition x ≈ 0.04. The presence of this topological threshold is established by direct and indirect evidence, such as peculiarities in the composition dependence of the basic parameters for electron diffraction and Raman vibration modes. The peculiarities are caused by the transition from a chain-ring-like structure to preferentially a chain-like structure. Experiments described in this section have shown that Raman technique is a particularly sensitive method to determine the presence of microcrystal's in the glassy matrix. Room-temperature polarized Raman scattering spectra of model glass have been collected. Low-frequency peaks were observed in the spectra. A model is proposed for explanation of their appearance. It is shown clearly that the low-frequency Raman spectra allow determining the conditions at the boundaries, sizes as well as concentration of micro-heterogeneities in non-crystalline materials. It was established earlier that for all amorphous (glassy) materials a low-frequency peak, observed in the corresponding spectral region of Raman scattering and called boson peak, is inherent. This peak is absent in crystals of the same chemical composition and is associated with space correlations on the scale of medium-range order R c ≈ 10 Å. On the contrary, less known is that a boson peak can give important information about the presence of microcrystalline inclusions and heterogeneities in the low-frequency Raman spectra of glasses irrespective to their chemical composition. [ABSTRACT FROM AUTHOR]