Search Results (4)

Triticum aestivum L. cv. Gazul is a spring wheat widely cultivated in Castilla y León (Spain). Potted plants were grown in a scenario emulating the climate change environmental conditions expected by the end of this century, i.e., with elevated CO₂ and high temperature under two water deficit regimes: long (LWD) and terminal (TWD). Changes in biomass and morphology, the content of proline (Pro), ascorbate (AsA) and glutathione (GSH), and enzymatic antioxidant activities were analyzed in flag leaves and ears. Additionally, leaf gas exchange was measured. LWD caused a decrease in biomass and AsA content but an increase in Pro content and catalase and GSH reductase activities in flag leaves, whereas TWD produced no significant changes. Photosynthesis was enhanced under both water deficit regimes. Increase in superoxide dismutase activity and Pro content was only observed in ears under TWD. The lack of a more acute effect of LWD and TWD on both organs was attributed to the ROS relieving effect of elevated CO₂. Gazul acted as a drought tolerant variety with anisohydric behavior. A multifactorial analysis showed better adaptation of ears to water deficit than flag leaves, underlining the importance of this finding for breeding programs to improve grain yield under future climate change. Full article

Predicted increases in the atmospheric CO₂ concentration and the earth’s mean surface temperature will be accompanied by a higher incidence of drought events. These environmental changes are likely to adversely affect crop productivity and quality, including wheat, an essential food in the human diet. We investigated the primary C-N metabolism response to drought stress at the whole-plant level and its dependence on plant development in bread wheat grown under combined elevated CO₂ and temperature. With this aim, the content of carbohydrates, nitrate, proteins and amino acids, together with the biomass were assessed in flag leaves and roots of wheat grown in controlled environment chambers at both ear emergence and anthesis stages. Multifactorial analysis revealed that the organ was the main factor explaining data variation. The physiological and biochemical traits in the flag leaves were more affected by drought than growth stage, leading to an accumulation of soluble carbohydrates, nitrate and amino acids. By contrast, roots were affected by the developmental stages but not by the treatment. The root content of fructose, glucose, starch and amino acids was higher at ear emergence than anthesis, whereas the accumulation of sucrose, fructans, proteins and nitrate increased at the latest growth stage. This study provides new insights into the reprograming of primary metabolism at whole plant level throughout the development in response to the future climate scenario, which could help to select traits ensuring sustainable food production systems that strengthen capacity for adaptation to climate change following the Sustainable Development Goals of 2030 Agenda. Full article

A rapid and high throughput protocol to measure the catalase activity in vitro has been designed. Catalase is an enzyme with unusual kinetic properties because it does not follow the standard Michaelis–Menten model and is inactivated by H₂O₂. This makes the analysis of the two rate equations of the second-ordered reactions of the kinetic model rather complex. A two-degree polynomial fitting of the experimental data is proposed after transforming the exponential form of the integrated rate equation of the [H₂O₂] into a polynomial using the Taylor series. The fitting is validated by establishing an experimental linear relationship between the initial rate of the H₂O₂ decomposition and the protein concentration, regardless of the suicide inactivation that catalase might undergo beyond t > 0. In addition, experimental considerations are taken into account to avoid statistical bias in the analysis of the catalase activity. ANOVA analyses show that the proposed protocol can be utilized to measure the initial rate of the H₂O₂ decomposition by catalase in 32 samples in triplicates if kept below 8 mM min⁻¹ in the microplate wells. These kinetic and statistical analyses can pave the way for other antioxidant enzyme activity assays in microplate readers at small scale and low cost. Full article

Usually, agricultural tractor investments are assessed using traditional economic techniques that only involve financial attributes, resulting in reductionist evaluations. However, tractors have qualitative and quantitative attributes that must be simultaneously integrated into the evaluation process. This article reports a hybrid and multi-attribute approach to assessing a set of agricultural tractors based on AHP-TOPSIS. To identify the attributes in the model, a survey including eighteen attributes was given to agricultural machinery salesmen and farmers for determining their importance. The list of attributes was presented to a decision group for a case of study, and their importance was estimated using AHP and integrated into the TOPSIS technique. In this case, one tractor was selected from a set of six alternatives, integrating six attributes in the model: initial cost, annual maintenance cost, liters of diesel per hour, safety of the operator, maintainability and after-sale customer service offered by the supplier. Based on the results obtained, the model can be considered easy to apply and to have good acceptance among farmers and salesmen, as there are no special software requirements for the application. Full article