Rice varieties characteristics

Biochemical basis of susceptibility or resistance of rice varieties to C. suppressalis has been studied in detail at IRRI recently (18). Allelochemics, mainly plant volatiles, were obtained from the ground leaf sheath tissue by steam distillation. The distillate was extracted with diethyl ether and after vacuum evaporation, a yellow oily residue was recovered which had the characteristic odor of each respective variety. The oily extracts of Rexoro (susceptible) and VTKM6V (resistant) varieties were tested as such, or as acid, basic, and neutral fractions for eliciting SSB moth s orientational and ovipositional responses. The whole extracts were also assayed for their effects on SSB eggs, larvae, and pupae. 

Suppression of weed growth by some rice varieties is often associated with their tillering characteristics and increase root biomass, which complicates the differentiation of allelopathic effects from competition for resources or superior vigor. In the case of rice, some of the most allelopathic cultivars indeed have larger root masses than non-allelopathic cultivars, but none of the QTLs associated with allelopathy were linked to QTLs associated with root morphology. 

The Strecker degradation of ornithine proceeds analogously, but the intermediate 4-aminobutanal forms by cychsation the final product, 1-pyrroHne (Figure 2.59). This reaction is important for the development of the characteristic aroma of bread crust (see Section 8.2.12.4.1), the aroma of other cereal products, certain fragrant rice varieties (such as Basmati rice) and in the biosynthesis of pyrrolidine alkaloids in plants (see Section 10.3.2.1.1). It was proposed that pyrrolidine and l-pyrrohne also result upon Strecker-type reaction of proline by a-dicarbonyl compounds. 

Table 3. Physiological characteristics of some varieties and lines of rice.

Substantial yield increases can also be achieved by exploiting the full genetic potential of seeds, whether by modern breeding technologies or genetic modification. Hundreds of new seed varieties with improved characteristics are introduced every year. Over the past 30 years, the yield of major field crops such as com, soya, wheat, and rice has increased by 60 to 80 percent and further increases are forecasted. Appropriate treatment of those seeds with crop protection chemicals before planting has proven to increase plant vigor overall. 

The varieties of rice examined in this study show only modest differences in trace element content between the Italian and Asian samples. The slight variations observed can be ascribed to specific characteristics of the botanical varieties, soil composition, and availability for each element, and local environmental contamination. The concentration of potentially toxic elements in rice ascertained in this study raise no specific concerns. On the other hand, the key role played by rice consumption in Asia diets calls for careful evaluation of the average daily intake for elements such as As, Cd, and Pb, which might exceed the established tolerance level. 

The brine may contain different types of flavorings and colorings. This results in different types of sufu products. A typical brine is one containing 12% NaCl and rice wine (-10% ethanol). The end product has a characteristic flavor and color, and very salty taste. Some varieties may have putrid flavor and be objectionable to some individuals. In commercial production, the product is finally bottled with brine, sterilized, and marketed. 

Emission of intrinsic fluorophores of crops depends on the structure of their microenvironments (molecular and / or cellular levels). We are going to describe here the emission of different varieties of corns (standard known as Safran, the amylose extender mutant and sweet) and of different varieties of white rice (Surinam, Thai, Sherbati and Basmati). Our results indicate that within each species, each variety has a characteristic fluorescence. Also we compared the emission of non genetically modified and genetically modified soya. Genetically modified organisms display fluorescence emission spectra different from those of the same non-GMO variety. 

The thermal degradation characteristics of lignocellulosic materials are strongly influenced by their chemical composition (cellulose, hemicellulose and lignin contents). The proportions of these constituents in rice husks vary to some extent between varieties, which may influence their kinetic behaviour 547250. The results of thermal degradation of rice husks show the two-step nature of the TG curves and the dual peak characteristics of the DTG curves, confirming the presence of two distinct reaction zones during... 

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