Methane (CH4) and nitrous oxide (N2O) are important greenhouse gases causing global warming and climate change. Efforts were made to analyze the CH4 and N2O flux in relation to plant and soil factors from rice (Oryza sativa L.) paddy. Ten popularly grown rice varieties namely Rashmisali, Bogajoha, Basmuthi, Lalkalamdani, Choimora (traditional varieties); Mahsuri, Moniram, Kushal, Gitesh and Profulla (high yielding varieties = HYV) were grown during monsoon season of July 2006. The CH4 and N2O emissions were measured the date of transplanting onwards at weekly interval along with soil and plant parameters. The seasonal integrated CH4 and N2O emission (Esif) from rice ranged from 8.13 g m(-2) to 13.00 g m(-2) and 121.63 mg N2O-N m(-2) to 189.46 mg N2O-N m(-2), respectively. Variety Gitesh emitted less N2O and CH4 amongst all the rice varieties. Both CH4 and N2O emission exhibited a significant positive correlation with leaf area, leaf number, tiller number and root dry weight. Soil organic carbon of the experimental field was associated with both CH4 and N2O emission whereas nitrate-N content of soil was associated with N2O emission. Methane emission showed significant positive correlations with soil temperature and crop photosynthetic rate. Traditional rice varieties with profuse vegetative growth recorded higher CH4 and N2O fluxes compared to HYVs. Gitesh and Kushal having low seasonal CH4 and N2O emission with higher yield potential can be recommended as low greenhouse gas emitting rice varieties.

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Sesame is important oilseed crop of tropical and sub tropical region, renowned for its high oil content (up to 60% oil), hence sesame is known as the king of oil seeds. Sesame seed oil contains 83% - 90% unsaturated fatty acids, 20% proteins and various minor nutrients such as vitamins and minerals, large amount of characteristic lignans, such as sesamin, sesamol, sesamolin and tocopherols. Sesame seeds with high amounts of nutritional components are consumed as a traditional health food for its specific antihypertensive effect, anticarcinogenic, anti-inflammatory and antioxidative activity. Besides food, sesame also finds its uses in application areas such as pharmaceutics, industrial, and as biofuel. Sesame is used as active ingredients in antiseptics, bactericides, viricides, disinfectants, moth repellants, and anti-tubercular agents. In spite of being a good source of “healthy oil” in terms of presence of high amounts of PUFA and high antioxidant content, it is not grown on a large extent due to very poor yields. Therefore, serious efforts are necessary for selecting varieties of good quality and high adaptive potential to the diverse climatic situations. There should be effective strategies adapted to produce climate ready sesame variety using modern biotechnological approach.

Experiments were conducted to study the dynamics of nitrous oxide (N₂O) emission from wheat varieties viz., Sonalika, HUW 468, HUW 234 and DBW 14 grown in alluvial soils of North Bank Plain Agroclimatic Zone of Assam, India. Attempts were made to find out the relationship of N₂O emission with plant morphophysiological, anatomical and soil properties. N₂O fluxes from wheat varieties ranged from 40 μg N₂O-N m⁻² h⁻¹ to 295 μg N₂O-N m⁻² h⁻¹. Soil organic carbon and soil temperature have shown significant relationship with N₂O flux. The rate of leaf transpiration recorded from the wheat varieties at different growth stages exhibited a positive correlation with N₂O emission suggesting that movement of N₂O along with the transpirational water flow may be an important mechanism of N₂O transport and emission through wheat plants. Anatomical investigation by scanning electron microscope revealed that N₂O emission has relationship with stomatal frequency of leaf and leaf sheaths. Variety HUW 234 with the highest stomatal frequency of leaf and leaf sheath also recorded higher seasonal N₂O emission compared to other varieties. Seasonal N₂O emission (E(sif)) of the varieties ranged from 3.25 to 3.81 kg N₂O-N ha⁻¹. Significant variations in E(sif) values were recorded within the varieties.

Among those various recent biotechnological tools, RNA Interference (RNAi) has been playing important role in crop improvement. RNAi can be defined as the ability of exogenous or endogenous double stranded RNA to suppress the expression of the gene which corresponds to the sequence of double stranded RNA. RNAi has been extensively used in various species to suppress gene function and is a novel approach to modify the gene expression for better quality traits and nutritional improvement in different crops. If judiciously used, this technology may go a long way to narrow the gap through production of disease, insect and virus resistant, nutritionally rich and toxic-free crops. The technology that has been developed by the developed countries will be available to any lab including those in the developing countries, where work utilizing RNAi technology is either in progress or going to be launched shortly. Ultimately this kind of technology can be important to global food security and also to maintain sustainability.

Fourteen pigmented hill rice cultivars along with a non-pigmented one were studied for ascertaining the extent of their nutritional and genetic diversity. Moisture contents of the fourteen pigmented hill rice cultivars ranged from 7.49 to 10.10 % along w.ith the contents (% dry weight) of nutrients viz., crude fat (4.37 -5.27) and crude protein (9.27 -11.42). The corresponding range of values for the contents (mg/100g dry weight) of microminerals Zn and Fe were form 3.42 to 4.28 and from 3.21 to 4.18 respectively. The pigmented germplasm had anthocyanin content (mg cyanidine 3-O glucoside /100g) ranging from 3.58 to 7.86, total phenolic content (mg GAE/100 g)from 67.89 to 89.43, flavonoid content (mg QE/100g)from 57.75 to 78.74 and antioxidant activity from 19.56 to 29.29 %. Analysis of variance indicated that the varietal effect on each of the parameters studied was highly significant. There was significant correlation amongst the different parameters of the rice genotypes analysed. Results of the biochemical screening of these cultivars may lead to selection of promising candidates that can be used for developing improved lines in future breeding programmes.

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