Distribution of Non-Structural Carbohydrates and Root Structure of Plantago lanceolata L. under Different Defoliation Frequencies and Intensities.

Plantago lanceolata L. (plantain) increases herbage dry matter (DM) production and quality during warm and dry conditions due to its deep roots and drought tolerance and reduces nitrogen losses in grazing systems compared to traditional pastures. However, plantain density usually declines after the third growing season, mainly due to defoliation management. The effects of defoliation frequency and intensity on water-soluble carbohydrate (WSC) reserves and below-ground plant responses need further research to optimize grazing strategies for improved productivity and sustainability of grazing systems. Our study investigated the effects of defoliation frequencies (15, 25, and 35 cm of extended leaf length, ELL) and intensities (5 and 8 cm of residual heights) on morphological traits and WSC concentrations in plantain biomass under controlled environmental conditions. Defoliation frequency significantly influenced morphological and chemical characteristics and biomass distribution more than residual height. Less frequent defoliations promoted above-ground herbage DM production, reproductive stems, and root biomass. Root architecture showed adaptations in response to defoliation frequency, optimizing resource acquisition efficiency. Frequent defoliation reduced high molecular weight WSC concentrations in leaves, affecting regrowth capacity and DM mass. A defoliation frequency of 25 cm ELL (~15 days) balances herbage production and root development, promoting long-term pasture sustainability.

Antioxidant Responses and Phytochemical Accumulation in Raphanus Species Sprouts through Elicitors and Predictive Models under High Temperature Stress.

Crop production is being impacted by higher temperatures, which can decrease food yield and pose a threat to human nutrition. In the current study, edible and wild radish sprouts were exposed to elevated growth temperatures along with the exogenous application of various elicitors to activate defense mechanisms. Developmental traits, oxidative damage, glucosinolate and anthocyanin content, and antioxidant capacity were evaluated alongside the development of a predictive model. A combination of four elicitors (citric acid, methyl jasmonate-MeJa, chitosan, and K2SO4) and high temperatures were applied. The accumulation of bioactives was significantly enhanced through the application of two elicitors, K2SO4 and methyl jasmonate (MeJa). The combination of high temperature with MeJa prominently activated oxidative mechanisms. Consequently, an artificial neural network was developed to predict the behavior of MeJa and temperature, providing a valuable projection of plant growth responses. This study demonstrates that the use of elicitors and predictive analytics serves as an effective tool to investigate responses and enhance the nutritional value of Raphanus species sprouts under future conditions of increased temperature.

Assessing Grain Quality Changes in White and Black Rice under Water Deficit.

Rice is an essential diet component for a significant portion of the population worldwide. Due to the high water demand associated with rice production, improving water use efficiency and grain quality is critical to increasing the sustainability of the crop. This species includes rice varieties with diverse pigmentation patterns. Grain quality, including industrial, nutritional, and functional quality traits, of two black rice genotypes and a commercial white rice cultivar were evaluated in different locations and under different water regimes. Flooding produced higher grain weight compared to alternate wetting and drying irrigation. A high correlation was found between grain color, total phenolic content (TPC), and antioxidant activity. The black rice genotypes showed higher TPC levels and antioxidant capacity, mainly due to higher levels of cyanidin 3-O-glucoside. The phenolic profile varied between whole and polished grains, while mineral composition was influenced by location and irrigation regime. In turn, the environment influenced grain quality in terms of industrial and nutritional characteristics, with significant differences in quality between whole and polished grains. This study provides valuable information on the genotype-environment relationship in rice and its effect on grain quality, which could contribute to selecting genotypes for an appropriate environment.

Native Species Facing Climate Changes: Response of Calafate Berries to Low Temperature and UV Radiation.

Calafate (Berberis microphylla G. Forst) is a wild bush plant widely distributed in the south of Argentina and Chile. Their blue colored fruits present particular flavor and health benefits attributed to high polyphenol contents biosynthesized by the plant under stress. Studies about correlation of abiotic conditions with anthocyanin profiles and physicochemical features of calafate beneath wild origin environment are not described yet. Hence, this research aimed to evaluate the physicochemical changes, antioxidant activity and anthocyanin content of calafate fruit in relationship to UV solar radiation (W.m-2) and air temperature (°C) environment condition during three consecutive years (2017, 2018, 2019). Variations in fruit anthocyanins were determined by comparison between high performance liquid chromatography (HPLC-DAD-ESI)/MSn and CIEL*a*b* colors parameters. Correlations were analyzed by principal component analysis (PCA). Radiation was negatively correlated with fruit size and weight. Physicochemical aspects such as pH, soluble solids, color, total anthocyanins, flavanols and other phenolic compounds were positively correlated with temperature changes. The quantities of monomeric anthocyanins were dependent on both low temperature and global radiation (reaching 20.01 mg g-1 FW in calafate fruit). These results constitute a valuable resource to understand the structural and physiological plasticity of calafate in facing climate changes for future domestication research as well as for agri-food industrial application.