Fault-tolerance embedding of rings and arrays in star and pancake graphs

The star and pancake graphs are useful interconnection networks for connecting processors in a parallel and distributed computing environment. The star network has been widely studied and is shown to possess attactive features like sublogarithmic diameter, node and edge symmetry and high resilience. The star/pancake interconnection graphs, {dollar}S\sb{n}/P\sb{n}{dollar} of dimension n have n! nodes connected by {dollar}{(n-1).n!\over2}{dollar} edges. Due to their large number of nodes and interconnections, they are prone to failure of one or more nodes/edges; In this thesis, we present methods to embed Hamiltonian paths (H-path) and Hamiltonian cycles (H-cycle) in a star graph {dollar}S\sb{n}{dollar} and pancake graph {dollar}P\sb{n}{dollar} in a faulty environment. Such embeddings are important for solving computational problems, formulated for array and ring topologies, on star and pancake graphs. The models considered include single-processor failure, double-processor failure, and multiple-processor failures. All the models are applied to an H-cycle which is formed by visiting all the ({dollar}{n!\over4!})\ S\sb4/P\sb4{dollar}s in an {dollar}S\sb{n}/P\sb{n}{dollar} in a particular order. Each {dollar}S\sb4/P\sb4{dollar} has an entry node where the cycle/path enters that particular {dollar}S\sb4/P\sb4{dollar} and an exit node where the path leaves it. Distributed algorithms for embedding hamiltonian cycle in the presence of multiple faults, are also presented for both {dollar}S\sb{n}{dollar} and {dollar}P\sb{n}{dollar}

Value Added Products Generation from Sugarcane Bagasse and Its Impact on Economizing Biorefinery and Sustainability of Sugarcane Industry

Augmenting value-added products generation with the biorefinery process of sugar cane by utilizing the by-products helps to achieve a more sustainable model of the sugarcane industry and in turn, contributes to the circular economy. Among the value-added products produced from sugarcane waste, functional foods offer additional health benefits besides their nutritional and calorific value. In recent years non-digestible sugars gained interest as potential prebiotic functional foods which benefit the host without increasing calorific value. These sugars are produced by the breakdown of carbohydrate polymers like cellulose and xylan, by thermochemical treatment or by enzymatic hydrolysis, or a combination of both. Sugar cane bagasse (SB) is an economical source of xylan which can serve as the substrate for xylooligosaccharides (XOS), xylobiose, xylitol, and ethanol. Cellulases, xylanases, and ligninases have wide applications in food processing, agro-fiber, pharmaceutical, and the paper and pulp industries including nutraceuticals production, where these enzymes provide eco-friendly alternatives to some chemical processes and help to reduce environmental impact. Conventional thermochemical methods for nutraceuticals production require chemicals that result in the release of toxic byproducts thus requiring additional steps for refining. In this context, the sustainable and eco-friendly processes for the production of nutraceuticals require employing biocatalysts like microbial enzymes or microbes as a whole, where in addition to averting the toxic byproducts the refining process requires lesser steps. The present chapter discusses the current research and challenges in the production of value-added products from sugarcane byproducts and their contribution to the sustainability of the sugarcane industry

Marker assisted introgression of bacterial blight resistance in Samba Mahsuri, an elite indica rice variety

Samba Mahsuri (BPT5204) is a medium slender grain indica rice variety that is very popular with farmers and consumers across India because of its high yield and excellent cooking quality. However, the variety is susceptible to several diseases and pests, including bacterial blight (BB). We have used PCR based molecular markers in a backcross-breeding program to introgress three major BB resistance genes (Xa21, xa13 and xa5) into Samba Mahsuri from a donor line (SS1113) in which all the three genes are present in a homozygous condition. At each backcross generation, markers closely linked to the three genes were used to select plants possessing these resistance genes (foreground selection) and microsatellite markers polymorphic between donor and recurrent parent were used to select plants that have maximum contribution from the recurrent parent genome (background selection). A selected BC4F1 plant was selfed to generate homozygous BC4F2 plants with different combinations of BB resistance genes. The three-gene pyramid and two-gene pyramid lines exhibited high levels of resistance against the BB pathogen. Under conditions of BB infection, the three-gene pyramid lines exhibited a significant yield advantage over Samba Mahsuri. Most importantly, these lines retain the excellent grain and cooking qualities of Samba Mahsuri without compromising the yield as determined in multi-location trials. This work demonstrates the successful application of marker-assisted selection for targeted introgression of multiple resistance genes into a premium quality rice variety

Introduction of bacterial blight resistance into Triguna, a high yielding, mid-early duration rice variety

Bacterial blight (BB) is a serious disease of rice in India. We have used molecular marker-assisted selection in a backcross breeding program to introgress three genes (Xa21, xa13, and xa5) for BB resistance into Triguna, a mid-early duration, high yielding rice variety that is susceptible to BB. At each generation in the backcross program, molecular markers were used to select plants possessing these resistance genes and to select plants that have maximum contribution from the Triguna genome. A selected BC3F1 plant was selfed to generate homozygous BC<SUB>3</SUB>F<SUB>2</SUB> plants with different combinations of BB resistance genes. Plants containing the two-gene combination, Xa21 and xa13, were found to exhibit excellent resistance against BB. Single plant selections for superior agronomic characteristics were performed on the progeny of these plants, from BC<SUB>3</SUB>F<SUB>3</SUB> generation onwards. The selected plants were subjected to yield trials at the BC<SUB>3</SUB>F<SUB>8</SUB> generation and were found to have a significant yield advantage over Triguna. The newly developed lines are being entered into national multi-location field trials. This work represents a successful example of the application of molecular marker-assisted selection for BB resistance breeding in rice