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1.
PLoS One ; 14(12): e0225555, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31826001

RESUMEN

Declines in agricultural biodiversity associated with modern farming practices may negatively affect the sustainability of agro-ecosystems, but formal knowledge of historical variation in spatio-temporal variation of agro-biodiversity is limited. We used time series of national (1947-2014) and district-level (1956-2008) crop distribution data for India to show that despite strong agricultural intensification after 1960, the average crop species diversity at the district level was stable, but increased at the country-level. While there was a decline in diversity in the major rice and wheat producing regions of northwestern India, associated with intensification of the production of these crops, diversity in western and southern India increased due to expansion of oilseeds and horticultural crops that replaced millet and sorghum. These opposite, but related, trends in crop-level diversity at the sub-national level partially canceled each other out at national level, but there nevertheless was a noticeable increase in overall crop diversity in India during this time period. Our results illustrate how patterns of change in crop diversity need to be considered at different levels of aggregation, and how a decrease in diversity associated with intensification and specialization in one area, may be associated with increased diversity elsewhere, and that support for intensive agriculture with relatively low crop diversity in some regions may be associated with an increase in crop diversity in other regions and at a higher level of aggregation.


Asunto(s)
Biodiversidad , Producción de Cultivos/estadística & datos numéricos , Productos Agrícolas/historia , Grano Comestible/historia , Producción de Cultivos/historia , Producción de Cultivos/métodos , Granjas/historia , Granjas/estadística & datos numéricos , Geografía , Historia del Siglo XX , Historia del Siglo XXI , India , Mijos , Oryza , Sorghum , Análisis Espacio-Temporal , Triticum
2.
J Food Sci ; 83(5): 1412-1421, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29624695

RESUMEN

The effect of two passive drying methods on the degradation of ascorbic acid (vitamin C),  α-tocopherol (vitamin E), and ß-carotene (provitamin A) in ripe mango and tomato was determined. Samples of both commodities were dried outdoors in a solar drying cabinet or indoors in sealed plastic boxes containing ceramic zeolite drying beads in a bead-to-fruit ratio of 1:10. Nutrient content of the dried samples was compared to fresh samples (undried control) obtained from the same batch of fruit. Mango samples tended to reach an equilibrium weight of approximately 18% of their initial weight after 28 to 30 hr of drying in both drying methods, while tomatoes equilibrated at 5% to 6% of their initial weight after 8 to 10 hr of drying in the solar drying cabinet and after approximately 30 hr using drying beads. The content of all three nutrients in solar dried tomato, and of ß-carotene in mango were significantly (P < 0.05) lower than the control. α-Tocopherol and ß-carotene content in tomato and ß-carotene content in mango were significantly lower than the control in samples dried using drying beads. Drying method had a significant (P < 0.05) effect on nutrient content; ascorbic acid and ß-carotene content were lower in solar dried tomato than in tomato dried with drying beads. For mango, ß-carotene content was lower after solar drying as compared to drying with drying beads. Drying fruit at lower temperatures using drying beads resulted in higher overall nutrient content of the dried fruit. PRACTICAL APPLICATION: Agriculturalists in developing countries still depend largely on solar drying methods as a means of extending the shelf life and increasing the value of fruit and vegetable products. Zeolite drying beads are reusable and are capable of drying fruit relatively quickly in a controlled environment, and may reduce the degradation of certain nutrients due to heat during solar drying.


Asunto(s)
Ácido Ascórbico/análisis , Desecación , Mangifera/química , Solanum lycopersicum/química , alfa-Tocoferol/análisis , beta Caroteno/análisis , Frío , Análisis de los Alimentos , Manipulación de Alimentos , Frutas/química , Calor , Luz Solar , Zeolitas
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