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The present investigation was carried out to understand the interrelationship and degree of dependence of grain yield on its components and gall midge incidence and to elucidate their relative importance. The experiment was conducted using 42 rice hybrids developed by crossing 6 CMS lines and seven testers in Line X Tester mating design, their parents and four checks. Observations were recorded on gall midge incidence, grain yield and fourteen component characters. Correlation coefficient analysis suggested that grain yield per plant had highly significant and positive association with panicle length (rp = 0.4600**, rg = 0.5545**) followed by number of grains per panicle (rp = 0.4219**, rg = 0.5125**) and number of productive tillers per plant (rp = 0.4006**, rg = 0.4942**) and negative non significant association with gall midge incidence (rp =-0.1154, rg =-0.1430). Panicle length had the highest positive direct effect (0.9688) followed by the number of grains per panicle (0.5748). Gall midge incidence showed a negative direct effect at the phenotypic level and a positive direct effect at the genotypic level on the grain yield per plant. Further, it showed indirect negative effects via plant height, number of productive tillers per plant, number of grains per panicle, spikelet fertility, hulling percentage, milling percentage, kernel length and kernel breadth as revealed from path analysis. The result of multiple linear regression exhibited that only the number of productive tillers per plant and the number of grains per panicle contributed significantly towards grain yield per plant. The step-wise regression analysis revealed that the panicle length, number of grains per panicle and number of productive tillers per plant were the most important characters having R=0.6505 and thus, could explain 42.31% of the total variation of grain yield. Gall midge incidence contributed to only 0.95% of the variation for grain yield, which might be due to the low incidence or resistance of the hybrids to the gall midge.

This chapter discusses in brief technology development in various aspects of ecophysiology and biochemistry of trees such as morphology and anatomy, general ecophysiology, specific techniques, formation of growth rings,, growth, and assessment of productivity, miscellaneous techniques, chemical composition of wood, etc.

Food waste (FW) and sewage sludge (SS) were anaerobically co digested under solid state conditions (Total solids >15%) and observed that mixing ratio of 3:1 and 2:1 is optimum for mesophilic and thermophilic conditions respectively. The VS reduction and methane yield at optimized ratio was 76% and 0.35 L CH4/(g VS reduced) respectively at mesophilic temperature whereas it was 88% and 0.42 L CH4/(g VS reduced) at thermophilic temperature. The metagenomic analysis for these cases were done and high throughput DNA sequencing revealed that diversified bacterial groups that participate in the different metabolisms (hydrolysis, acidogenesis and acetogenesis) were mainly dominated by the phylum Firmicutes and Bacteriodetes. Genus Methanothrix is found to be dominant which is capable of generating methane by any methanogenic pathway among all the archaeal communities in the reactors followed by Methanolinea and Methanoculleus. However, it was understood through metagenomic studies that acetotrophic pathway is observed to be the major metabolic pathway in the reactors.

This study investigated the impact of the potential cellulose degrading bacteria that could be bioaugmented in the solid-state anaerobic digestion (SSAD) of bagasse to enhance the methane yield. The prospective anaerobic cellulose degrading bacteria was isolated from the soil. SSAD experiments were organized with & without bioaugmentation with a substrate total solid (TS) of 25%, 30%, 40% and 50% at an optimized feed to microorganism (F/M) ratio of 1:1. The maximum yield of 0.44 L CH4/ (g VS added) was obtained from bioaugmented bagasse at a TS of 40% whereas it was 0.34 L CH4/(g VS added) for non-bioaugmented bagasse. The isolated bacterial strain was identified that belongs species Pseudomonas of Gamma Proteobacteria which exhibited good cellulolytic activity. Metagenomic studies found 90% of archaeal microorganisms affiliated to Methanosaeta, a strict acetoclastic methanogen.

Microorganisms are smart enough to evolve within the anaerobic ecosystems with tiny alteration in the process of fermentation as per the system dynamics. This study tries to elucidate the change in community structure of the consortia in anaerobic digestion of rice straw, bagasse, press mud, and vegetable waste with respect to its complexity. With the aid of metagenomic studies, it is found that Bacteroidetes and Firmicutes dominated the metabolic pathway for generation of precursors for methane production. The highest methane yield of 0.38 L CH4/(g VSadded) was obtained for rice straw followed by bagasse, press mud and vegetable waste. However, maximum VS reduction of 70% was observed for vegetable waste followed by rice straw (67%), baggase (60%) and press mud (60%). Acetoclastic methanogenesis is the dominating methane metabolic pathway with Methanosaeta dominating archaea in all the reactors.