Climate is the primary factor influencing the feasibility of agricultural production. Given the context of climate change, prospective studies become imperative for anticipating potential consequences on plant development and the adaptation of agricultural systems. The objective of this study is to compare two methods based on the calculation of climatic indicators, which can reveal risks of production losses. The first method relies on agroclimatic indicators (AGIs), computed on fixed calendar dates corresponding to plant development phases. The second method employs phenoclimatic indicators (PHI), calculated between previously simulated phenological stage dates. To provide a concrete comparison and account for a range of potential climate scenarios, the cultivation of soft winter wheat (Triticum aestivum) in Clermont-Ferrand is used as an example for horizons 2060 and 2100 under the RCP 4.5 and 8.5 scenarios (using the ALADIN63_CNRM-CM5 model from Météo-France). A comparison of the two methods yields contrasting results. It emphasizes the effectiveness of PHIs in closely approximating the conditions encountered by a specific plant, without undermining the significance of AGIs in interpreting changes in diverse climatic parameters that affect plant development overall. The AGIs indicate a rise in water deficit and hot days for soft wheat in 2060 and 2100. Meiosis would be less susceptible to low temperatures, and bolting would benefit from a slightly higher cumulative radiation. Conversely, depending on the chosen sowing dates, the PHIs indicate that heat days and water deficit would not be more pronounced than in the reference period, owing to the earlier physiological maturity date of the grains. However, advancing the bolting date on the calendar would expose it to a lack of radiation and low temperatures. Consequently, recommendations for adaptation and transition in the agricultural sector may vary significantly between the results of AGIs and those of PHIs.

Climate is the primary factor influencing the feasibility of agricultural production. Given the context of climate change, prospective studies become imperative for anticipating potential consequences on plant development and the adaptation of agricultural systems. The objective of this study is to compare two methods based on the calculation of climatic indicators, which can reveal risks of production losses. The first method relies on agroclimatic indicators (AGIs), computed on fixed calendar dates corresponding to plant development phases. The second method employs phenoclimatic indicators (PHI), calculated between previously simulated phenological stage dates. To provide a concrete comparison and account for a range of potential climate scenarios, the cultivation of soft winter wheat (Triticum aestivum) in Clermont-Ferrand is used as an example for horizons 2060 and 2100 under the RCP 4.5 and 8.5 scenarios (using the ALADIN63_CNRM-CM5 model from Météo-France). A comparison of the two methods yields contrasting results. It emphasizes the effectiveness of PHIs in closely approximating the conditions encountered by a specific plant, without undermining the significance of AGIs in interpreting changes in diverse climatic parameters that affect plant development overall. The AGIs indicate a rise in water deficit and hot days for soft wheat in 2060 and 2100. Meiosis would be less susceptible to low temperatures, and bolting would benefit from a slightly higher cumulative radiation. Conversely, depending on the chosen sowing dates, the PHIs indicate that heat days and water deficit would not be more pronounced than in the reference period, owing to the earlier physiological maturity date of the grains. However, advancing the bolting date on the calendar would expose it to a lack of radiation and low temperatures. Consequently, recommendations for adaptation and transition in the agricultural sector may vary significantly between the results of AGIs and those of PHIs.