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A bandgap bowing parameter of 0.4 ± 0.2 eV for β-(AlxGa1−x)2O3 alloys, with Al compositions (x) up to 0.35, has been determined from the bandgap obtained from low temperature optical reflectivity, which suppresses the effect of electron–phonon interaction on the bandgap. A length scale of inhomogeneity of 0.21 ± 0.03 times of the electron–hole mean free path length has been estimated for β-(AlxGa1−x)2O3 alloys. The unit cell of β-(AlxGa1−x)2O3 alloys compresses, and the lattice parameters vary linearly with Al substitution. Our results provide insight into bandgap engineering and alloy disorder for β-(AlxGa1−x)2O3 alloys, which are an important material system for applications in deep ultraviolet opto-electronic devices.

Mungbean is an important leguminous crop providing protein for the rural and urban poor in South and Southeast Asia. An experiment was conducted in free air carbon dioxide enrichment facility (FACE) ring to study the impact of increased CO2 level on growth and biomass partitioning in mungbean crop. The crop was grown under ambient (400 μmol mol-1) and elevated CO2 concentration (550 μmol mol-1) with 5 doses of P with and without cyanobacterial inoculation. Elevated CO2 significantly increased biomass accumulation in mungbean crop which was further increased by P and cyanobacteria application. Leaf biomass increased by 34.4% at increased CO2 level. Maximum biomass allocation to seeds was observed with P dose of 16 mg kg-1 soil in both ambient and elevated CO2 conditions. Allocation was more in high CO2 treatment. The study concludes that mungbean crop grown under elevated CO2 condition accumulates more biomass which gets further improved by application of P nutrient and cyanobacteria inoculation.

In this paper, the climate change scenarios of A2 and B2 for 2070-2100 time scale (denoted as 2080) for several key locations of India and its impact on rice and wheat crops based on regional climate model (PRECIS) were described. The PRECIS projects an increase in temperature over most parts of India especially in the IGP (Indo-Gangetic Plains), the region that presently experiences relatively low temperatures. Extreme high temperature episodes and rainfall intensity days are projected to become more frequent and the monsoon rainfall is also projected to increase. Rabi (mid Nov-March) season is likely to experience higher increase in temperature which could impact and hence become threat to the crops which really require low temperature for their growth. Climatic variability is also projected to increase in both A2 and B2 scenarios. All these projected changes are likely to reduce the wheat and rice yields in Indo-Gangetic plains of India. It is likely that there will be more number of years with low yields occurs towards the end of the century. Such yield reductions in rice and wheat crops due to climate change are mediated through reduction in crop duration, grain number and grain filling duration. The yield loss will be more in A2 scenario compared to B2. These quantitative estimates still have uncertainties associated with them, largely due to uncertainties in climate change projections, future technology growth, availability of inputs such as water for irrigation, changes in crop management and genotype. These projections nevertheless provide a direction of likely change in crop productivity in future climate change scenarios.

Recently Chatterjea (1) has proved a theorem to deduce a bilateral generating function for the Ultraspherical polynomials. In the present paper an attempt has been made to give a general version of Chatterjea's theorem. Finally, the theorem has been specialized to obtain a bilateral generating function for a class of polynomials {Pn(x;α,β)} introduced by Bhattacharjya (2).

A field experiment was conducted inside a temperature gradient tunnel (TGT) at the ICAR-Indian Agricultural Research Institute, New Delhi during rabi 2014-15 to quantify the impacts of elevated temperature on thermal requirement, growth and yield of wheat crop. Wheat crop was subjected to five temperature treatments, i.e. +0ºC (representing ambient condition), +0.9ºC, +2.5ºC, +2.8ºC and +3.5ºC.Temperature elevation of 3.5°C increased accumulated growing degree days (GDD) and photo-thermal unit (PTU), thereby hastening maturity of the crop. Leaf area index (LAI) of the crop was affected most by the high temperature at the anthesis stage. Temperature elevation by 2.5°C and above significantly reduced the LAI of wheat. Grain weight decreased by 17.1%, while the straw weight reduced by 10.5% with temperature elevation of 3.5°C. Temperature elevation by 2.5°C and above significantly reduced the straw weight, but grain weight of wheat got significantly reduced even with 0.9°C elevated temperature. Reduced number of spikes per/m2 and number of grains/spike decreased grain yield. In fact, the increase in the spikelet sterility contributed towards the grain yield reduction. The information generated from this study will help in developing the appropriate management practices for production of wheat crop.

Wheat (Triticum aestivum L.) crop is one of the most valuable crops, and further boost in wheat yields is essential to meet the food demand of the emerging world population. It is therefore necessary to know the influence of future climate change on wheat yields. Present investigation was conducted in temperature gradient tunnel (TGTs) to evaluate the effects of elevated temperature, CO2 concentration,weed and their interactions on grain, biological yield and other yield attributes (number of spikes/m2, number of spikelets/spike, number of grains/spike and 1000-grain weight, harvest index) of wheat. Wheat crop was grown in TGT at three different temperature levels, i.e. T1 ambient, T2 ambient+1.5°C, T3 ambient+3°C and two levels of carbon dioxide, i.e. ambient (ACO2) 400 ppm and elevated (ECO2) 550±50 ppm with and without weed interaction.The study revealed that yield and yield attributes of subsequent wheat crop increased due to ECO2. Mean individual effect of ECO2 increased grain yield of wheat by 14% and biological yield by 12% compared to ACO2. On the contrary, the yield was decreased with elevated temperature where a decrease in the grain yield from ˗12% to ˗20% and biological yield from ˗11% to ˗18% was observed at 1.5°C and 3°C, respectively. Similarly the interaction of weeds in wheat crop, reduced the grain yield by 8% and biological yield of wheat by 6%, irrespective of CO2 and temperature levels.The statistical analysis (P

Thermal power plants (TPP) are a major source of air pollutants particularly suspended particulate matter (SPM) which either remains suspended in air or gets deposited onto soil surface and crop canopy in adjoining areas thereby affecting the growth and productivity of crops. Keeping this in view, a study was undertaken near Dadri TPP situated at NTPC Dadri, Uttar Pradesh, to assess the impact of aerial deposition on crops grown in adjoining areas. Eight different locations situated in different villages located at varying distance within 1-10 km radius were selected for study. Rice (Oryza sativa L.) and wheat (Triticum aestivum L.) fields were identified in the selected villages and their growth and yield parameters were recorded during the entire crop duration. Aerial deposition load on crop canopy was also quantified. Results showed that rice and wheat crops grown nearer to the TPP were most affected in terms of reduction in growth and yield as compared to fields located at far off distances. This was attributed to the deposition of SPM on rice and wheat leaves, which reduced photosynthesis rate leading to lower leaf area index, biological and grain yield of both the crops. In wheat crop, aerial deposition load on leaves was found to be more than rice at all stages. Reduction in grain yield in rice within10 km radius were 13.5% and 20.4%, while in wheat reduction were 21.9% and 19.1% in first and second year of study, respectively. The zone of 1 to 3 km radius from the TPP was found to be most vulnerable in terms of yield loss both in rice and wheat crops. In this zone some more resistant alternative crops can be grown which will help farmers to increase their productivity and income.