Moisture stress is the major constraint to rice production and its stability in rainfed, mainly irrigated, and aerobic environments. Identification of genomic regions conferring tolerance to stress would improve our understanding of the genetics of stress response and result in the development of drought tolerant cultivars. In the present study, quantitative trait loci for drought response related traits and as well as grain yield were identified using a set of 140 recombinant inbred lines derived from a cross between the popular high-yielding variety, IR64 and the landrace, INRC10192. A total of 36 QTL were identified for grain yield and its components under control and stress conditions. Strikingly, a QTL cluster flanked by the markers RM38 and RM331 on chromosome 8 was found to be associated with grain yield, plant height, no. of productive tillers, chaffy grains, and spikelet fertility on secondary rachis and biomass under stress treatment. The genomic regions associated with these QTL under drought stress will be useful for the development of marker-based breeding for drought tolerant, high-yielding varieties suited to drought-prone areas.Drought is the most devastating among abiotic stresses and it depresses yield by 15 -50% depending on the vigor and period of stress in rice. In the course of origin, domestication, and further evolution of rice, natural selection has been in favor of retaining traits of adaptability for its survival, whereas breeding by man has been towards selective improvement of traits of agronomic value such as higher yield, duration of choice, plant type, etc. Detailed studies of drought tolerance have enabled us to understand the physiological responses of plants, although our understanding of its genetic basis remains poor. Like yield and its components, traits that confer tolerance to the stress, directly or indirectly, are controlled by many genes, with each contributing a relatively small effect on the overall phenotype.Most of the past efforts to combine drought tolerance in highyield backgrounds have been a futile exercise, largely because of its genetically complex nature and lack of precise screening or selection protocols. Availability of high density marker linkage maps, annotated genome sequence, and powerful biometric methods has enabled identification and use of trait-specific genes/QTL for directed improvement of rice. It started with the pioneering discovery of yield QTL in wild/weedy species in rice by Xiao et al. (1998) closely followed by Brondani et al. (2002)

With the global consciousness of climate change, renewable energy systems are prioritized over the conventional energy systems. The deep injection of renewables into the power systems is creating several challenges to the grid due to wide variations in their output power depending on the time of the day, weather etc. Of these challenges, frequency change plays a vital role in maintaining the power quality. This paper presents a novel sliding mode controller with non-linear disturbance observer to effectively mitigate the wide changes in the frequency. A sliding mode surface based on estimated disturbance along with states is designed. A sliding mode control law is proposed to compensate disturbances including variations in renewables, load and parameters under mismatched uncertainties. The proposed observer based controller is tested for three area multi-machine power system in MATLAB/Simulink. The simulated results proved to alleviate the frequency variations effectively compared to the conventional controllers.

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A major dwarfing region for plant height, asd1, was identified employing the next-generation sequencing-based QTL-Seq approach from a dwarf mutant and is demonstrated to be responsible for the dwarf nature with least penalty on yield in rice. The yield plateauing of modern rice is witnessed since many decades due to the narrow genetic base owing to the usage of a single recessive gene, i.e., semi-dwarf-1 (sd-1) for development of short-statured varieties throughout the world. This calls for the searching of alternate sources for short stature in rice. To this end, we made an attempt to uncover yet another, but valuable dwarfing gene employing next-generation sequencing (NGS)-based QTL-Seq approach. Here, we have identified a major QTL governing plant height on chromosome 1, i.e., alternate semi-dwarf 1 (asd1) from an F mapping population derived from a cross between a dwarf mutant, LND384, and a tall landrace, INRC10192. Fine mapping of asd1 region employing sequence-based indel markers delimited the QTL region to 67.51 Kb. The sequencing of the QTL region and gene expression analysis predicted a gene that codes for IWS1 (C-terminus family protein). Furthermore, marker-assisted introgression of the asd1 into tall landrace, INRC10192, reduced its plant height substantially while least affecting the yield and its component traits. Hence, this novel dwarfing gene, asd1, has profound implications in rice breeding.

Differential response of seedling characteristics under water stress conditions is known to be associated with drought resistance in rice and elucidation of its genetics could be of help in breeding for tolerance to the stress. A recombinant inbred population derived from the cross between a semi-dwarf variety IR64 and landrace INRC10192 was grown in hydroponic culture and phenotyped for varied responses of seedlings to water deficit imposed by poly ethylene glycol (PEG). The ratio between mean value of seedling trait under stress and control conditions was used for assessing drought tolerance. In all 19 putative QTLs relating to five seedling traits viz., shoot length, maximum root length, shoot dry weight, root dry weight and root to shoot dry weight ratio under PEG induced stress conditions were identified confirms that the traditional tall landraces as

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