Indian Institute of Technology Guwahati

About: Indian Institute of Technology Guwahati is a education organization based out in Guwahati, Assam, India. It is known for research contribution in the topics: Adsorption & Catalysis. The organization has 6933 authors who have published 17102 publications receiving 257351 citations.

Tailoring Microalgae for Efficient Biofuel Production

Abstract: Depleting fossil fuel, soaring price, growing demand and global climate change concerns have driven research for finding alternative source of sustainable fuel. Microalgae have emerged as a potential feedstock for biofuel production as many strains accumulate high amounts of lipid, with faster biomass growth and higher photosynthetic yield than that of their land plant counterparts, without needing agricultural land or ecological landscapes, and offering opportunities for mitigating global climate change allowing waste water treatment and CO2 sequestration. Despite these benefits, microalgae pose many challenges, including low lipid yield under limiting growth conditions and slower growth in high lipid content strains. Biotechnological interventions can make major advances in strain improvement for commercial scale production of biofuel. We discuss various strategies including efficient transformation toolbox, and to increase lipid accumulation and its quality through regulation of key enzymes involved in lipid production, blocking the competing pathways, pyramiding genes, enabling high cell biomass under nutrient deprived conditions and other environmental stresses, and controlling the upstream regulators of targets, the transcription factors and microRNAs. We highlight the opportunities emerging from the current progress in application of genome editing in microalgae for accelerating strain improvement program.

Spatial variability of chlorophyll and nitrogen content of rice from hyperspectral imagery

Abstract: Chlorophyll and nitrogen are the most essential parameters for paddy crop growth. Spectroradiometric measurements were collected at canopy level during critical growth period of rice. Chemical analysis was performed to quantify the total leaf content. By exploiting the ground based measurements, regression models were established for chlorophyll and nitrogen aimed indices with their corresponding crop growth variables. Vegetation index models were developed for mapping these parameters from Hyperion imagery in an agriculture system. It was inferred that the present Simple Ratio (SR) and Leaf Nitrogen Concentration (LNC) indices, which followed a linear and nonlinear relationship respectively, were completely different from published Tian et al. (2011). The nitrogen content varied widely from 1 to 4% and only 2 to 3% for paddy crop using present modified index models and Tian et al. (2011) respectively. The modified LNC index model performed better than the established Tian et al. (2011) model as far as estimated nitrogen content from Hyperion imagery was concerned. Furthermore, within the observed chlorophyll range obtained from the studied rice varieties grown in the rice agriculture system, the index models (LNC, OASVI, Gitelson, mSR and MTCI) performed well in the spatial distribution of rice chlorophyll content from Hyperion imagery. Spatial distribution of total chlorophyll content varied widely from 1.77 to 5.81 mg/g (LNC), 3.0 to 13 mg/g (OASVI), 0.5 to 10.43 mg/g (Gitelson), 2.18 to 10.61 mg/g (mSR) and 2.90 to 5.40 mg/g (MTCI). The spatial information of these parameters will help in proper nutrient management, yield forecasting, and will serve as inputs for crop growth and forecasting models for a precision rice agriculture system.