International Food Policy Research Institute

About: International Food Policy Research Institute is a nonprofit organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Agriculture & Food security. The organization has 1217 authors who have published 4952 publications receiving 218436 citations.

Screening and HPLC methods for carotenoids in sweetpotato, cassava and maize for plant breeding trials.

Abstract: Analytical methods for sweetpotato, cassava and maize were developed. In orange and salmon-fleshed sweetpotatoes, (all-E)-?-carotene predominated and results of spectrophotometric screening and HPLC quantification did not differ significantly. In yellow-fleshed sweetpotato and cassava, however, spectrophotometric screening overestimated the HPLC values because of the presence of several minor carotenoids. Aside from (all-E)-?-carotene, Z-isomers were present in cassava in appreciable amounts. For both crops, extraction with acetone or tetrahydrofuran:methanol (1:1), using a mortar and pestle or a Polytron homogenizer, gave equivalent results. Rehydration of dry maize at room temperature for 30 min or at 85 °C for 5, 10 or 15 min gave equivalent results. Concentrations obtained with the C18 and C30 columns did not differ significantly for zeaxanthin, lutein, ?-cryptoxanthin and ?-carotene in the all-E-configuration, but their Z-isomers were difficult to locate in the chromatogram obtained with the C30 column. Extraction with tetrahydrofuran:methanol (1:1) gave significantly lower results for zeaxanthin and lutein.

The Rapid Rise of Cross-Regional Agricultural Mechanization Services in China

Abstract: Although Adam Smith (1776) and Alfred Marshall (1920) emphasized the gains from specialization that arise from the division of labor,their focus was on the manufacturing sector. Both saw farming as being on too small a scale and bereft of economies of scale, with a market that was too small and local, with too sharp a seasonality, and too quick a succession of tasks to support either the development of a division of labor over the tasks of a cropping season or of mechanization. Smith and Marshall’s vision of farming— and its implications for division of labor and mechanization—was manifest again in the 1950s to the present in Asia. Ruttan (2001) puts forward nearly the same ideas and terms as Smith and Marshall, but for contemporary small rice farms in Asia. He emphasizes that the use of machines for the series of short tasks performed on tiny farms would imply costly investment in specialized machines that small farmers would be loath to make. And even if these farmers mechanized, Ruttan posited that it would not induce a segmented and specialized farm labor market as,again,the critical mass of demand for each segment would not be present. Otsuka (2012) goes further along these lines to note that only on larger farms would the mechanization investment,