Drought represents significant environmental stress, and improving agriculture water management and yield is a priority goal. The effect of diminishing soil water content in the grain filling (GF) stage, throughout physiological maturity (GM), on the yield and grain quality, leaf water potential (LWP), and maximum quantum yield (Fv/Fm) in four long photoperiod quinoa genotypes was evaluated in the South-Central zone of Chile, during the 2014–2015 and 2015–2016 seasons. Five irrigation treatments (T) were established. Irrigation was carried out when the available water (AW) of the root zone reached values of 100%, 70%, 40%, 20%, and 0%. The lowest LWP values were obtained by T20 and T0 (−1.95 MPa). The ‘Morado’ genotype reached the lowest LWP at both seasons, while the highest average LWP was achieved by the ‘AG 2010’ (2014–2015) and ‘Cahuil’ genotypes (2015–2016). A global trend of Fv/Fm values was observed from GF to GM: 0.74 toward 0.79 (2014/2015), and 0.74 toward 0.82 (2015/2016). Only during the second season, Fv/Fm showed differences among irrigation treatments. Total average grain yields in the second season (2.97 t ha⁻¹) were greater than those in the first season (1.43 t ha⁻¹). In both seasons, the ‘Cahuil’ genotype and T100 reached the highest yields. A significative decrease in yield was observed when AW diminished. A direct relationship between seed yield and leaf water potential (ΔY/ΔLWP) was found in all genotypes, varying between 5.53 (‘Cahuil’) and 2.86 t ha⁻¹ MPa⁻¹ (‘AG 2010’). Total proteins, albumins, and globulins varied between seasons, with almost no differences among irrigation treatments. Only the ‘Morado’ genotype showed a slight trend to obtain a higher content of total protein in both seasons. It is possible to grow quinoa under irrigation deficit conditions between GF throughout GM, maintaining yield parameters and nutritional quality.

Red clover persistence has been one of the major targets for the most breeding programs worldwide. A phenotypic characterization at above- and belowground level was performed to a set of highly persistent red clover populations. The objective was to identify phenotypic changes occurring after empirical selection for plant survival, which is the consensus criteria of persistence. Eleven red clover populations were established on mesocosms of polyvinyl chloride (PVC) tubes of 11 cm in diameter and 100 cm depth, containing as substrate a mixture (v/v) of sand, vermiculite, soil and perlite. The trial was organized in a randomized complete block design with four replicates, each replicate consisting of five mesocosms per population and one plant per mesocosm. In total, 220 mesocosms were handled. At aboveground level, growth parameters, specific leaf area (SLA) and shoot dry matter (ShootDM) were measured. At belowground level, root morphology (volume, diameter and length) and topology (altitude, external path length [EPL] and dichotomous branching index [DBI]) were measured through image analyses. Analyses of variance were performed implementing a phenotypic linear mixed model using the Restricted Maximum Likelihood method. Additionally, variance components were estimated and broad-sense heritability was calculated for each phenotypic trait. Highly persistent cultivars exhibited 30% higher ShootDM and 10% lower leaf size and SLA than the oldest low-persistent cultivar Quiñequeli. At root level, they showed 20, 50 and 50% higher crown diameter, root length density and root volume than Quiñequeli, respectively, but 20% lower DBI. Root traits exhibited medium-low values of genetic control; broad sense heritability ranged between 0.20 and 0.48. In conclusion, highly persistent red clover cultivars and experimental lines bred in Chile modified their phenotypic expression of individual plants at shoot and root levels relative to the oldest low persistent cultivar Quiñequeli. Associations among above- and belowground traits offer opportunities for designing more efficient selection strategies. For instance, the strong relationship between SLA and root traits offers tremendous potential for indirect phenotypic selection.

RESUMEN El daño por sol y la falta de color de frutos producida por el exceso de radiación solar y altas temperaturas es el mayor problema productivo en los huertos de manzano en Chile. El objetivo de esta investigación fue evaluar el uso de mallas de colores como herramienta para el control de daño por sol y mejorar la coloración en manzanas. Durante la temporada 2012-13 y 2013-14 un huerto de manzanos ´Fuji´ y ´Gala´ fue cubierto con mallas de color Roja y Perla al 20% de sombreado, dejando árboles sin cubrir como control. Se realizó un registro de la temperatura del aire y fruto (ºC), humedad relativa (%) y radiación fotosintéticamente activa total (PARtotal) y difusa (PARdifusa) (µmol m-2 s-1). Al momento de cosecha se cuantificó la incidencia de daño por sol con escala visual (%) y el color de frutos a través de un equipo Color Hunter. En promedio, para ambas temporadas, la malla Roja redujo la transmisión de PARtotal en un 21%, mientras que la malla Perla en un 17%. La cantidad PARdifusa fue en promedio un 15% superior bajo la malla Perla que la malla Roja, incrementando con ello el desarrollo de color rojo de frutos en el cultivar Fuji. Durante la temporada 2012/13 ambas mallas redujeron en un 26% y 44% el daño por sol en frutos para los cultivares Gala y Fuji, respectivamente. Durante la temporada 2013/14 las mallas no redujeron significativamente el daño por sol en los frutos. Los resultados de este estudio sugieren que la malla Perla provee de mejores condiciones de luz para el desarrollo de color rojo de frutos en huertos de manzanos. No obstante, bajo las condiciones climáticas de Chile, ambas mallas (Roja y Perla) presentan una efectividad solo relativa para el control de golpe de sol en manzanas.

The increasing water scarcity affects the agricultural sector, and it is a significant constraining factor for crop production in many areas of the world. Water resource management and use related to crop productivity is the most important factor in many crops. Since consumer demands healthy food, the nutritive quality and the active ingredient need to be considered within the productive issue. The objective of this study was to determine water technical efficiency related to seed yield and seed protein content and composition in quinoa (Chenopodium quinoa Willd.) under water stress using data envelopment analysis (DEA). The study was conducted in Chillan, Chile in two growing seasons. As water availability increased, seed yield, globulin, and albumin yield increased, particularly in the genotype Cahuil. The higher average efficiency levels for the DEA were 46.7% and 39.2% in Cahuil in both seasons at 20% available water (AW). The highest average efficiency of globulin yield was recorded in the same genotype (Cahuil). The highest multi-product technical efficiency levels in all input and output included in this study were observed in Cahuil, Regalona, and Morado under water scarcity in both seasons. In future studies related to crop management, DEA provides a good framework for estimating efficiency under restricted factors and multi-product results.