Abstract Amaranth and quinoa belong to the family Amaranthaceae characterized by having species that grow in adverse conditions, in addition to presenting high contents of proteins, unsaturated fatty acids and vitamins, as well as functional properties, which could be an excellent option to face the great problems that afflict the world. Due to these characteristics, quinoa has become a worldwide phenomenon and is already grown in more than 100 countries. The study was proposed in order to determine if amaranth has the agronomic potential to increase the cultivated area as happened with quinoa. An experiment was established with three varieties of quinoa and three varieties of amaranth in three environments of the Highs Valleys of Mexico, under a randomized complete block design with an arrangement of treatments in split plots. Agronomic variables, as well as yield, were evaluated. The results found showed that amaranth surpassed quinoa in inflorescence length, inflorescence width, stem diameter, hectoliter weight and yield, while quinoa presented higher values for seed diameter and weight of one thousand seeds. The Tlahuicole and L-145 amaranth genotypes observed the best performance, followed by the Suyana variety of quinoa. Amaranth has characteristics to be a worldwide phenomenon, as has happened with quinoa.

Resumen El Amaranto y la quinua pertenecen a la familia Amaranthaceae caracterizada por tener especies que crecen en condiciones adversas, además de presentar altos contenidos de proteínas, ácidos grasos insaturados y vitaminas, además propiedades funcionales, que podrían ser una excelente opción para hacerle frente a los grandes problemas que aquejan al mundo. Debido a estas características la quinua se ha convertido en un fenómeno a nivel mundial y ya se cultiva en más de 100 países. La investigación fue planteada con el fin de determinar si el amaranto tiene el potencial agronómico para incrementar la superficie cultivada como sucedió con la quinua. Se estableció un experimento con tres variedades de quinua y tres variedades de amaranto en tres ambientes de los Valles Altos de México, bajo un diseño de bloques completos al azar con arreglo de tratamientos en parcelas divididas. Se evaluaron variables agronómicas, así como el rendimiento. Los resultados encontrados mostraron que el amaranto superó a la quinua en longitud de inflorescencia, ancho de inflorescencia, diámetro de tallo, peso hectolítrico y rendimiento, mientras que la quinua presentó valores más altos para diámetro de semilla y peso de mil semillas. Los genotipos Tlahuicole y L-145 de amaranto fueron los que observaron mejor comportamiento, seguidos por la variedad Suyana de quinua. El amaranto presenta características para ser un fenómeno a nivel mundial, tal como ha sucedido con la quinua.

ABSTRACT The purpose of this study was to determine the measured and simulated rates of soil organic carbon (SOC) change in Vertisols in short-term experiments when the tillage system is changed from traditional tillage (TT) to conservation tillage (CT). The study was conducted in plots in four locations in the state of Michoacán and two locations in the state of Guanajuato. In the SOC change simulation, the RothC-26.3 carbon model was evaluated with different C inputs to the soil (ET1-ET5). ET was the measured shoot biomass (SB) plus estimated rhizodeposition (RI). RI was tested at values of 10, 15, 18, 36 and 50 % total biomass (TB). The SOC changes were simulated with the best trial where ET3 = SB + (0.18*TB). Values for model efficiency and the coefficient of correlation were in the ranges of 0.56 to 0.75 and 0.79 to 0.92, respectively. The average rate of SOC change, measured and simulated, in the study period was 3.0 and 1.9 Mg ha−1 yr−1, respectively; later, in a simulation period of 45 years, SOC change was 1.2 ± 0.8. In particular, without making adjustments in the RothC parameters and with information on measured plant residue C inputs to the soil, it was possible to simulate changes in SOC with RothC and estimate trends over a period of more than 45 years.

The objective of this work was to simulate, by the RothC model, the changes in soil organic carbon (SOC) caused by changes of land use - from the traditional maize-squash (TMC) association to systems with castor bean (Ricinus communis): multilayer (MUL), alleys (CALL) and monoculture (HIG). SOC simulations were performed for 0-20 and 0-40 cm soil depths, for the period 1980-2040, considering the TMC system as the base line. SOC change rates estimated with RothC, for both soil depths, were 0.5-1.2, 0.4-0.8, 0.3-0.5 and 0.04-0.1 Mg ha-1 C per year in the HIG, MUL, CALL and TMC systems, respectively, and were consistent with those reported in the literature. RothC perfomance had 89% efficiency (EF) and R² = 0.9, which shows that this model can be used with scarce SOC temporal information, information on the history of land use, and with input measurements of aerial and underground plant residues in the soil.

El objetivo del presente trabajo fue la simulación de los cambios del carbono orgánico del suelo (COS), por el modelo RothC, en razón del cambio de uso de suelo del sistema tradicional - asociación maíz-calabaza (TMC) - a sistemas con higuerilla (Ricinus communis): multiestratos (MUL), callejones (CALL) y monocultivo de higuerilla (HIG). Las simulaciones del COS se hicieron para las profundidades de suelo 0-20 y 0-40 cm, para el periodo de 1980-2040, considerándose como línea base al sistema TMC. Las tasas de cambio de COS estimadas con el RothC, en ambas profundidades de suelo, estuvieron en 0,5-1,2, 0,4-0,8, 0,3-0,5 y 0,04-0,1 Mg ha-1 de C por año en los sistemas HIG, MUL, CALL y TMC, respectivamente, y fueron consistentes con las reportadas en la literatura. El desempeño del RothC tuvo 89% de eficiencia (EF), con R²=0,9, lo que muestra que este modelo puede usarse con información temporal del COS escasa, información de la historia de uso de suelo y mediciones de la entrada de residuos vegetales aéreos y subterráneos en el suelo.