Physiological traits associated with recent advances in yield of Chinese wheat

[spa] China representa alrededor del 20% de la población mundial y esta proporción se mantendrá similar en las próximas décadas y por tanto la mejora en la dieta incrementará el consumo de trigo. Aunque los rendimientos de grano en trigo han ido aumentando en las últimas tres décadas, la alimentación de casi 1400 millones de personas en las próximas décadas supone un reto significativo. Para satisfacer esta demanda, es fundamental estudiar qué rasgos agronómicos y fisiológicos pueden contribuir a un mayor rendimiento potencial en trigo. Para lograr este objetivo, los trigos de la provincia de Henan, una de las regiones productoras de trigo de China, se han estudiado en esta tesis. Los objetivos de este estudio fueron identificar la combinación de rasgos agronómicos, morfológicos y fisiológicos que han contribuido a las mejoras sustanciales en el rendimiento potencial de los trigos de invierno chinos recientemente comercializados y evaluar técnicas de fenotípado que pueden ayudar a acelerar los nuevos avances en la selección de trigos chinos. El rendimiento potencial de los genotipos modernos chinos ha aumentado como resultado de un incremento del índice de cosecha (HI), el número de granos por unidad de superfície, y la biomasa aeria total, mientras que el peso de mil granos ha sido menos afectada. Por el contrario, la mayoría de los genotipos de alto rendimiento están moderadamente adaptados a condiciones de estrés y son altamente sensibles a las cepas de roya amarilla en condiciones Mediterráneas de alto rendimiento, lo que indica que la adaptación al estrés no ha sido una prioridad en la selección recientemente realizada en China en condiciones de rendimiento potencial. El “ideotipo” adaptado al estrés consiste en plantas más altas con una mayor biomasa aérea verde, sobretodo durante la etapa reproductiva, junto con un mejor estado hídrico, la capacidad de absorber agua durante el llenado del grano y una mayor eficiencia en el uso del nitrógeno relacionada con una captación y utilización más eficiente de los fertilizantes nitrogenados. Por otra parte, la fotosíntesis neta (Pn) y la conductancia estomática (gs) en las hojas bandera no parecen estar relacionadas con el aumento del rendimiento potencial, mientras que el CO2 total fijado por toda la espiga parece tener un papel claro en el aumento del rendimiento. Estudios de composición isotópica de carbono (δ13C) y oxígeno (δ18O) han sugerido que el aumento de la eficiencia del uso del agua está implicado en el aumento de rendimiento potencial. Sin embargo, dicho aumento no se logró a través de una disminución de la gs. Por el contrario, los genotipos de alto rendimiento potencial tienen una mayor eficiencia en el uso del nitrógeno (NUE), una mayor capacidad de removilización del N y de absorción de agua durante el llenado del grano. Estas mejoras se lograron mediante la optimización del balance fuente / sumidero de N en la espiga, que es principalmente el resultado de la liberación de N procedente de la degradación de Rubisco durante el llenado del grano.[eng] China represents around 20% of world population and this proportion will remain similar in the coming decades, whereas an improvement in diet will increase the consumption of wheat. Although wheat grain yields have been increasing in the last three decades, the challenges of feeding nearly 1.4 billion people will be significant in the next few decades. To satisfy this demand, it is paramount to study what agronomical and physiological traits may contribute to higher yield potential in wheat. Towards this goal, wheats from Henan Province, which is one of the wheat baskets of China, have been studied in this thesis. The objectives of this study were to identify the combination of agronomical, morphological and physiological traits that have contributed to the substantial improvements in yield potential of recently released Chinese winter wheats and to test phenotypical approaches that may help to speed further breeding advances in Chinese wheats. The yield potential of modern Chinese genotypes has grown as a result of an increase in harvest index (HI), grain number per unit area, and total above-ground biomass, whereas thousand kernel weight has been less affected. By contrast, most of the high yield genotypes are moderately adapted to stress conditions and highly susceptible to yellow rust strains in high-yielding Mediterranean conditions, indicating that stress adaptation has not been a priority in recent Chinese breeding for yield potential conditions. The stress adapted “ ideotype” consists of taller plants with a higher green aerial biomass, particularly during the reproductive stage, together with a better water status, the capacity to take up water during grain filling and a higher nitrogen use efficiency that is related to a more efficient uptake and utilization of N fertilizer. Moreover, the net photosynthesis (Pn) and stomatal conductance (gs) in flag leaves do not appear to be related to increases in yield potential, while total CO2 fixed by the whole ear appears to have a clear role in the yield increase. Studies of carbon (δ13C) and oxygen (δ18O) isotope composition have suggested that higher water use efficiency is involved in raising yield potential. However, such an increase was not achieved through a decrease in gs. By contrast, the high yield potential genotypes have higher nitrogen use efficiency (NUE), N remobilization capacity and uptake capacity during grain filling. These improvements were achieved by optimizing the ear N source/sink balance, which is mainly the result of N released from Rubisco degradation during grain filling. Besides detecting the physiological traits contributing to raising yield potential, testing for effective phenotyping tools to assess stress tolerance is important in breeding. This is the case for biotic stresses, such as yellow rust, where the use of low cost phenotyping approaches may help to select rust tolerance in the breeding pipeline. The use of conventional (i.e. red/blue/green, RBG) images provided an affordable approach to detect genotypic tolerance to yellow rust. Some colour characteristics, including hue, green fraction, greener fraction, a, and u have proved to be more efficient than other more conventional phenotyping approaches

Agronomical and analytical trait data assessed in a set of quinoa genotypes growing in the UAE under different irrigation salinity conditions

The importance of quinoa has been emphasized considerably in the recent decades, as a highly nutritional crop seed that is tolerant to salinity and amenable to arid agronomical conditions. The focus of this paper is to provide raw and a supplemental data of the research article entitled "Agronomic performance of irrigated quinoa in desert areas: comparing different approaches for early assessment of salinity stress" [1], aiming to compare different approaches for early detection, at the genotypic and crop levels, of the effect of salinity caused by irrigation on the agronomic performance of this crop. A set of 20 genotypes was grown under drip irrigation in sandy soil, amended with manure, at the International Center for Biosaline Agriculture (UAE) for two weeks, after which half of the trial was submitted to irrigation with saline water and this was continued until crop maturity. After eight weeks of applying the two irrigation regimes, pigment contents were evaluated in fully expanded leaves. The same leaves were then harvested, dried and the stable carbon and nitrogen isotope compositions (δ13C and δ15N) and the total nitrogen and carbon contents of the dry matter analyzed, together with ion concentrations. At maturity yield components were assessed and yield harvested. Data analysis demonstrated significant differences in genotypes response under each treatment, within all assessed parameters. The significant level was provided using the Tukey-b test on independent samples. The present dataset highlights the potential use of different approaches to crop phenotyping and monitoring decision making

Relative contribution of nitrogen absorption, remobilization, and partitioning to the ear during grain filling in chinese winter wheat

Knowledge of the function of the ear as a key organ in the uptake, remobilization and partitioning of nitrogen is essential for understanding its contribution to grain filling and thus guiding future breeding strategies. In this work, four Chinese winter wheat genotypes were grown on a 15N-enriched nutrient solution. N absorption and further remobilization to the flag leaf, the ear and the mature grains were calculated via the 15N atom%excess. The results indicated that the high yields of the Chinese wheat genotype were determined by higher grain numbers per ear, with greater plant height and a larger ear size, while the thousand-grain weight did not affect grain yield. In the mature grains, 66.7% of total N was remobilized from the pre-anthesis accumulation in the biomass, while the remaining 33.3% was derived from the N taken up during post-anthesis. From anthesis to 2 weeks after the anthesis stage, the flag leaf remobilized 3.67mg of N outwards and the ear remobilized 3.87mg of N inwards from the pre-anthesis accumulation in each plant. The positive correlation between ear Nrem and grain Nrem indicated that the ear was an important organ for providing N to the grain, whereas the remobilized N stream from the leaves was not correlated with grain Nrem, thus indicating that flag leaf N was not translocated directly to the grain. The grain Nrem was negatively correlated with the ear N concentration throughout grain filling, which suggested that higher-yielding genotypes had better sink activity in the ear, while Rubisco played a critical role in N deposition. Therefore, to improve yield potential in wheat, the N accumulation in the ear and the subsequent remobilization of that stored N to the grains should be considered. N accumulation and remobilization in the ear may at least be valuable for Chinese breeding programs that aim at optimizing the sink/source balance to improve grain filling

“Interpreting Buddhist Precepts with Confucian Rites” Based on Their Similarity and Dissimilarity: A Perspective of the History of Ideas in Wei, Jin, and Northern and Southern Dynasties

The “similarity” (gongtong 共通) and “dissimilarity” (chayi 差異) between the Buddhist precepts and Confucian rites in the Wei, Jin, and Southern and Northern Dynasties reflected a “dialogue of civilizations” (wenming duihua 文明對話) at the levels of concept, system, and life. During these periods, the Chinese system of rites were compared and interpreted with the Buddhist monastic codes by Buddhist monks and Confucian scholars, so a history of the ideas interpretation process of “interpreting precepts with rites” (yi li shi jie 以禮釋戒) was achieved. The result of such a process was two-fold: from the perspective of lay Buddhist ethics, they were in common with each other; from the perspective of monastic precepts, they were irreconcilable contradictions. Thus, on the one hand, the eminent Chinese monks “were emulating the Confucian rites to justify Buddhist precepts” (ni li yi zheng jie 擬禮義證戒) to stress their commonalities. On the other hand, the differences between the precepts and rites continued to be discovered, and the Buddhist subjective consciousness (zhuti yishi 主體意識) of “the distinction between precepts and rites” (jie li you bie 戒禮有別) was gradually established

Changes in bio-accessibility, polyphenol profile and antioxidants of quinoa and djulis sprouts during in vitro simulated gastrointestinal digestion

This study aimed to evaluate the bio-accessibility of the phenolics and flavonoid, the polyphenolic profile and the antioxidant activity of sprouts obtained from four different quinoa genotypes and one djulis cultivar during in vitro gastrointestinal digestion. Compared to their content in sprouts, the bioavailable phenolics after the oral phase, the gastric phase, the intestinal phase, and in the dialyzable fraction were in the ranges of 45.7%–63.5%, 87.6%–116.7%, 89.6%–124.5%, and 7.4%–10.9%, respectively. The trend in flavonoid bio-accessibility was similar to the polyphenols. The dialyzable flavonoid recoveries varied between 4.2% and 12.4%. Correspondingly, the free radical scavenging activity of the dialyzable phase decreased significantly from 84.7% to 96.5%. The main phenolic acids were vanillic acid, caffeic acid, and syringic acid during digestion. The results suggest that gastrointestinal digestion greatly affected the absorption of polyphenols and flavonoid of quinoa and djulis sprouts, as well as their antioxidant capacity

Response of a Sylvan Moss Species (<i>Didymodon validus</i> Limpr.) with a Narrow Distribution Range to Climate Change

Mosses are particularly susceptible to climate change owing to their close biological and ecological associations with climatic conditions. However, there is a limited understanding of the changes in distribution patterns of the moss species in forest ecosystems under climate change, especially in mosses with narrow ranges. Therefore, we reconstructed historical, simulated present, and predicted future potential distribution patterns of Didymodon validus, a narrow-range moss species in the forest ecosystem, using the MaxEnt model. The aim of this study was to explore its unique suitable habitat preference, the key environmental factors affecting its distribution, and the distributional changes of D. validus under climate change at a long spatial-time scale. Our findings indicate that the most suitable locations for D. validus are situated in high-altitude regions of southwestern China. Elevation and mean temperature in the wettest quarter were identified as key factors influencing D. validus distribution patterns. Our predictions showed that despite the dramatic climatic and spatial changes over a long period of time, the range of D. validus was not radically altered. From the Last Interglacial (LIG) to the future, the area of the highly suitable habitat of D. validus accounted for only 15.3%–16.4% of the total area, and there were weak dynamic differences in D. validus at different climate stages. Under the same climate scenarios, the area loss of suitable habitat is mainly concentrated in the northern and eastern parts of the current habitat, while it may increase in the southern and eastern margins. In future climate scenarios, the distribution core zone of suitable habitat will shift to the southwest for a short distance. Even under the conditions of future climate warming, this species may still exist both in the arid and humid regions of the QTP in China. In summary, D. validus showed cold and drought resistance. Our study provides important insights and support for understanding the impact of climate change on the distribution of D. validus, as well as its future distribution and protection strategies

Changes in bio‐accessibility, polyphenol profile and antioxidants of quinoa and djulis sprouts during in vitro simulated gastrointestinal digestion

This study aimed to evaluate the bio-accessibility of the phenolics and flavonoid, the polyphenolic profile and the antioxidant activity of sprouts obtained from four different quinoa genotypes and one djulis cultivar during in vitro gastrointestinal digestion. Compared to their content in sprouts, the bioavailable phenolics after the oral phase, the gastric phase, the intestinal phase, and in the dialyzable fraction were in the ranges of 45.7%–63.5%, 87.6%–116.7%, 89.6%–124.5%, and 7.4%–10.9%, respectively. The trend in flavonoid bio-accessibility was similar to the polyphenols. The dialyzable flavonoid recoveries varied between 4.2% and 12.4%. Correspondingly, the free radical scavenging activity of the dialyzable phase decreased significantly from 84.7% to 96.5%. The main phenolic acids were vanillic acid, caffeic acid, and syringic acid during digestion. The results suggest that gastrointestinal digestion greatly affected the absorption of polyphenols and flavonoid of quinoa and djulis sprouts, as well as their antioxidant capacity

Physiological, hormonal and metabolic responses of two alfalfa cultivars with contrasting responses to drought

Alfalfa (Medicago sativa L.) is frequently constrained by environmental conditions such as drought. Within this context, it is crucial to identify the physiological and metabolic traits conferring a better performance under stressful conditions. In the current study, two alfalfa cultivars (San Isidro and Zhong Mu) with different physiological strategies were selected and subjected to water limitation conditions. Together with the physiological analyses, we proceeded to characterize the isotopic, hormone, and metabolic profiles of the different plants. According to physiological and isotopic data, Zhong Mu has a water-saver strategy, reducing water lost by closing its stomata but fixing less carbon by photosynthesis, and therefore limiting its growth under water-stressed conditions. In contrast, San Isidro has enhanced root growth to replace the water lost through transpiration due to its more open stomata, thus maintaining its biomass. Zhong Mu nodules were less able to maintain nodule N2 fixing activity (matching plant nitrogen (N) demand). Our data suggest that this cultivar-specific performance is linked to Asn accumulation and its consequent N-feedback nitrogenase inhibition. Additionally, we observed a hormonal reorchestration in both cultivars under drought. Therefore, our results showed an intra-specific response to drought at physiological and metabolic levels in the two alfalfa cultivars studied.This work was supported by the i-COOP-suelos y legumbres (2016SU0016) call funded by the National Research Council. David Soba is the recipient of a PhD grant supported by the Public University of NavarraPeer reviewe

Yield, Agronomic and Forage Quality Traits of Different Quinoa (Chenopodium quinoa Willd.) Genotypes in Northeast China

Quinoa (Chenopodium quinoa Willd.) grain is well known as a source of nutritious human food, but the nutritional properties of quinoa as animal fodder has not been well explored. Fifteen quinoa accessions were assessed for grain and forage yields, and morphological and quality traits during anthesis and grain filling, with the aim of selecting superior genotypes for greater production and quality traits that are well adapted to northeastern China. Variations were significant among the tested genotypes for all traits. The highest grain weight was recorded in Rainbow (27.51 g plant&minus;1), followed by the local Chinese genotypes Longli 3, YY28 and Mengli 1. Correlation analysis revealed a significant positive association of grain yield with branches and a negative association with culm thickness and inflorescence length, whereas more branches and moderate plant height were the main yield components affecting yield. Forage shoot weight was 37.2&ndash;81.6 g plant&minus;1, with JQ3 and ZQ1 exhibiting the highest yields. Forage yield was strongly and positively correlated with most of the morphological traits, except plant height, and was negatively associated with chlorophyll content and the fresh/dry matter ratio. Quality traits and the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of quinoa were significantly lower than alfalfa (Medicago sativa L.), oats (Avena sativa L.) or Leymus chinensis (Trin.) Tzvel, and the crude protein (CP) content was significantly higher than all three species, reaching above 20%. The saponin content of the whole plant was higher during anthesis than during grain filling. In conclusion, genotypes having more branches and shorter and more compact main inflorescences achieved higher grain yields, whereas genotypes possessing thick stems, more branches and moderate plant height produced more forage. Hence, the results indicate that superior quinoa genotypes have great potential to solve fodder shortages in China