Leaf senescence in plants is the last stage of leaf development and is characterized by a decline in photosynthetic activity, an active degeneration of cellular structures, and the recycling of accumulated nutrients to areas of active growth, such as buds, young leaves, flowers, fruits, and seeds. This process holds economic significance as it can impact yield, influencing the plant’s ability to maintain an active photosynthetic system during prolonged periods, especially during the grain filling stage, which affects plant weight and oil content. It can be associated with different stresses or environmental conditions, manifesting itself widely in the context of climate change and limiting yield, especially in crops of agronomic relevance. In this work, we study the stability of two widely described sunflower (Helianthus annuus L.) genotypes belonging to the INTA Breeding Program against differential N conditions, to verify their yield stability in control conditions and under N supply. Two inbred lines were utilized, namely R453 (early senescence) and B481-6 (late senescence), with contrasting nitrogen availability in the soil but sharing the same ontogeny cycle length. It was observed that, starting from R5.5, the B481-6 genotype not only delayed senescence but also exhibited a positive response to increased nitrogen availability in the soil. This response included an increase in intercepted radiation, resulting in a statistically significant enhancement in grain yield. Conversely, the R453 genotype did not show significant differences under varying nitrogen availability and exhibited a tendency to decrease grain yield when nitrogen availability was increased. The response to nitrogen can vary depending on the specific genotype.

Leaf senescence in plants is the last stage of leaf development that is characterized by a decline in photosynthetic activity, an active degeneration of cellular structures and the recycling of accumulated nutrients to areas of active growth such as buds, young leaves, flowers, fruits and seeds. This process holds economic significance as it can impact yield, influencing the plant´s ability to maintain an active photosynthetic system during prolonged periods, especially during the grain filling stage, which affects plant weight and oil content. It can be associated with different stresses or environmental conditions, manifesting itself widely in the context of climate change and limiting yield, especially in crops of agronomic relevance. In this work we study the stability of two widely described sunflower genotypes belonging to the INTA Breeding Program against differential N conditions, to verify their yield stability in control conditions and under N supply. Two inbred lines were utilized, namely R453 (early senescence) and B481–6 (late senescence), with contrasting nitrogen availability in the soil but sharing the same ontogeny cycle length. It was observed that, starting from R5.5, the B481-6 genotype not only delayed senescence but also exhibited a positive response to increased nitrogen availability in the soil. This response included an increase in intercepted radiation, resulting in a statistically significant enhancement in grain yield. Conversely, the R453 genotype did not show significant differences under varying nitrogen availability and exhibited a tendency to decrease grain yield when nitrogen availability was increased. The response to nitrogen can vary depending on the specific genotype.

Water deficit is one of the main abiotic stresses that affect wheat production worldwide. Plants exhibit phenotypic variations to mitigate the negative effects of water stress on grain yield. The objective of the work was to evaluate whether wheat (Triticum aestivum L.) plants showed transgenerational inheritance of environmental adaptation when exposed to water deficit around flowering (i.e. the critical phenological stage for the definition of grain yield). During the first experimental year, plants from three genotypes (PIF: commercial cultivar; TR1 and TR4: transgenic genotypes derived from PIF containing the transcription unit pSARK::IPT --associated with the cytokinin-induced enhanced drought tolerance--) were cultivated under well-watered (WWm) or water deficit from Z3.2 to Z6.9+5 days (WDm). Offspring of this first year were then grown under well-watered (WWo) or water deficit from Z3.2 to Z6.9+5 days (WDo) during the next two years, following a crop arrangement. Plants from seeds exposed to WDm tended to have a poor grain yield for both water regimes of the progeny (i.e. WWo and WDo) in both years. The number of grains per unit area was the numerical component that best explained grain yield (r2=0.98; p<0.05), due to variations in the number of grains per ear. Grain weight was a highly conservative trait. Aboveground biomass and harvest index reduced in response to WDo compared to WWo and followed similar responses to grain yield. In conclusion, a restrictive maternal water environment worsened yield response in the following generation, independent of the water condition to which the offspring were exposed, due to reductions in the number of grains per spike, in total aboveground biomass at maturity, and in its partitioning to the grain.

Producers in the Argentine Pampas often fail to fully replenish the nutrients extracted by crops, leading to unsustainable soil fertility management. The objectives of this study were to (i) evaluate grain yield, mineral nutrient concentration, and extraction for maize ( Zea mays L.), wheat ( Triticum aestivum L.), and soybean ( Glycine max L. Merr.) under contrasting agronomic management systems and (ii) compare mineral nutrient concentration with nutrient removal values commonly used as reference in Argentina when assessing crop nutrient soil uptake. The study was conducted over 8 years in a field experiment located in the central Rolling Pampas, under three crop sequences: continuous soybean (Sy), a 2‐year rotation alternating maize and soybean (Mz–Sy), and a 3‐year rotation including wheat/soybean double crop, maize, and soybean (Wt/SyDC–Mz–Sy). In addition, these were evaluated with either fallow or winter cover crops (CCs) present under two agronomic systems: conventional management (CM) and intensified management (IM). The IM system included different genotypes, plant densities, fertilizer types, and rates. The IM increased yield for Mz by 1.25 Mg ha ⁻¹ ( p < 0.01), Wt by 0.82 Mg ha ⁻¹ ( p < 0.05), Sy1 (soybean full season crop) by 0.28 Mg ha ⁻¹ ( p < 0.05), and SyDC by 0.39 Mg ha ⁻¹ ( p < 0.05). The inclusion of a CC decreased yield for Mz by 1.20 Mg ha ⁻¹ (p < 0.01) and Sy1 by 0.34 Mg ha ⁻¹ (p < 0.05), only within CM and in the drier years. The IM increased nitrogen (N) and sulfur (S) concentrations for Sy but had no consistent effects on nutrient concentrations in other crops. Observed grain nutrient concentration values, despite their variability, could be used to estimate nutrient exports by these crops.