Variación morfológica en flores de Capsicum annuum y C. chinense por el incremento de temperatura y CO2

<p><strong>Background:</strong> Temperature and atmospheric CO₂ concentration strongly influence the biological cycle of plants, particularly during the reproductive stage. These environmental factors have been altered by anthropogenic activity, affecting flower morphology and fertility. <strong>Objective:</strong> To evaluate the floral morphology of <em>Capsicum annuum</em> and <em>C. chinense</em> under high temperature and elevated CO₂ conditions. <strong>Methodology:</strong> Plants were grown in four controlled-environment chambers: T1 = control (30 °C, 400 µmol mol⁻¹), T2 = 30 °C and 1200 µmol mol⁻¹, T3 = 40 °C and 400 µmol mol⁻¹, and T4 = 40 °C and 1200 µmol mol⁻¹. Morphometric traits of sepals, petals, androecium, and gynoecium were recorded throughout flower development. <strong>Results:</strong> In <em>C. annuum</em>, flowers from T2 were larger from the earliest stages, significantly surpassing the other treatments after day 13 and reaching their maximum size on day 19 (19.1 ± 0.27 mm). In <em>C. chinense</em>, the same treatment reached its largest size on day 17 (13.3 mm). Elevated CO₂ increased petal and ovary area in both species, whereas high temperature reduced filament length, style width, ovary diameter, and the number of ovules per ovary. It also decreased pollen quantity and viability. In all treatments, flower temperature was higher than ambient air temperature. <strong>Implications:</strong> Elevated CO₂ partially offset the negative effects of heat stress by promoting floral organ growth; however, high temperature impaired reproductive structures and potential fertility. <strong>Conclusion:</strong> Elevated CO₂ enhanced floral development in <em>Capsicum</em> species, whereas high temperature reduced pollen viability and reproductive efficiency, potentially limiting fruit set under future climate change scenarios.</p>