No abstract

En diversos estados del país, como Nuevo León, aún en la actualidad existe una considerable diversidad de variedades de maíz (Zea mays L.) que no han sido exploradas ni estudiadas suficientemente y cuya recolección es necesaria como fuente de germoplasma. El objetivo del presente trabajo fue realizar una recolecta de poblaciones nativas de maíz en las regiones de la Gran Llanura de Norteamérica, Llanura Costera del Golfo Norte y Sierra Madre Oriental, para su conservación ex situ, caracterización y futuro aprovechamiento en diferentes programas de mejoramiento genético. En 2008 se recolectaron 135 poblaciones nativas de maíz, de las cuales 49.63% correspondió a razas puras y 50.33% a cruzas interraciales. Las poblaciones nativas obtenidas provinieron de las regiones de la Sierra Madre Oriental (42%), Llanura Costera del Golfo Norte (30%) y Sierra Madre Oriental (28%). El germoplasma recolectado se conservó en el Banco Central de maíz del INIFAP, en Texcoco, Estado de México. Las recolecciones de germoplasma, como una fuente de diversidad genética deben ser caracterizadas para un manejo eficiente y un aprovechamiento efectivo que permita el mejoramiento y la productividad en el estado. No se descarta la posibilidad de que se haya perdido a través de los años, germoplasma reportado con anterioridad, por lo que las recolectas de maíces nativos deben de continuar en las regiones fisiográficas de Nuevo León.

To identify eco-efficient bean cultivars that can be planted at high densities for sustainable bean production under climate change, this study analyzed the performance of ten dry bean (Phaseolus vulgaris L.) cultivars grown at 90,000, 145,000 and 260,000 plants ha−1 under rainfed semi-arid conditions in Mexico. The study compared the yield and yield components (leaf area index (LAI), pods per plant, and hundred seed weight) of the cultivars. We also analyzed the dry matter distribution (DMD), growth rate (GR), radiation use efficiency (RUE), and harvest index (HI) of the best performing cultivars to determine how they respond to higher densities. The cultivars were established under similar planting and management conditions during two growing seasons. The precipitation for the first and second seasons were 175 and 492 mm, respectively, representing 57% and 160% of the mean precipitation in the area during the July–October growing period. Pinto Saltillo, a drought-tolerant indeterminate semi-prostrate cultivar, and Azufrado 2, a determinate shrub cultivar, performed best at high densities under low-precipitation conditions (175 mm). Both cultivars responded to the highest density (260,000 plants ha−1) with increases of 54% to 69% (0.7 to 1.1) in LAI and 21% to 86% (0.32–0.81 Mg ha−1) in yield. The two cultivars responded to increasing plant density with a modification in their fraction of DMD over plant parts and a change in their GR from 0.23–0.25 at low density to 0.96–1.74 gr m−2 day−1 at high density. The two cultivars had an RUE of 3.8 to 4.4 g MJ−1 and HI of 0.31 to 0.36 at high planting density. Farmers’ use of these commercially available cultivars proven to have high yields and the ability to respond favorably to high densities under rainfed conditions can be a viable short-term strategy to increase dry bean production for sustainable agriculture in semi-arid temperate regions.

Introduction. The State of Nuevo Leon is considered the depositary of a wide genetic diversity of creole avocados (Persea americana var drimyfolia). Objective. The aim of this work was to determine the variability of the total oil content and the fatty acids profile in creole avocados from Nuevo Leon, Mexico. Materials and methods. During the spring and summer of 2016, 36 varieties of creole avocados were collected in the northern and southern region of the State of Nuevo Leon, Mexico for chemical characterization. The commercial variety “Hass” was included as a control. To determine the variability that exists in the content of total oils and fatty acids in the collected materials, analyzes of the main components and conglomerates were carried out. Results. Six fatty acids were detected in the total oil of the creole avocados: palmitic, stearic, oleic, palmitoleic, linoleic and linolenic. The outstanding varieties were “Platano temprano”, “Platano delgado”, “Huevo de toro”, “Cuerno”, “Pato”, and “Especial”, which presented an average of 17.28, 24.93 and 66.29 % more in the content of oleic, linoleic and linolenic acids respectively, and an average of 28.12 % less stearic acid compared to the commercial variety “Hass”. According to the analysis of main components, materials with high oleic acid content usually have low palmitic and palmitoleic acid contents. The dendrogram presented six groups within the evaluated materials, most of the outstanding materials are located in groups one and four. Conclusion. High variability in the content of total oils and fatty acids was determined in creole avocados from Nuevo Leon. Therefore, they are considered promising for their incorporation into genetic improvement programs.

The prediction of crop yield and harvest volume of about 700 thousand ha planted to dry bean in Zacatecas State will enable the implementation of strategies to decrease the degree of uncertainty of decisions pertaining to agriculture. The purpose of the present study was to predict bean yield under rainfed conditions using leaf area index (LAI), light interception (LI) by the canopy, and rainfall. LAI and LI of both black-grain and light-colored grain beans were determined at the beginning of flowering, at pod formation, at the beginning of pod filling, and at intermediate pod filling. The relationship yield: LAI/LI/rainfall as well as the verification of a model were examined by linear least-square regression. Maximal LI and its LAI for the various years were 70 % and 1.6 for 2002 and 75 % and 2.5 in 2003. For these years, LI as a function of LAI could be described by an exponential model. LAI and LI at pod formation and the beginning of pod filling were the phenological stages that better explained bean yield for all varieties. The empirical model relating bean yield: LAI/LI/rainfall accounted for 71 % of the variability of light-colored grain bean yield. The corresponding percentages of the variability in measured yields for black-grain beans were 68 % for Emiliano Zapata and Progreso and 74 % for Zaragoza and Miguel Auza. Even though the relationship LAI/LI/rainfall was affected due to the low plant population density, the many varieties employed, and the agroecological sites, the information from this kind of studies will be useful to decision makers and farmers to make decisions.