Genotypic Variation in Physiological and Biochemical Responses among Local Fig (Ficus carica L.) Varieties Grown in Northern Morocco

The fig (Ficus carica L.) is one of the oldest fruit crops cultivated in arid and semi-arid regions, valued for both its nutritional and economic importance. Thus, ensuring sustainable fig production under climate change conditions is very important as water scarcity increasingly affects fruit quality and production. This study assessed the physiological and biochemical parameters in the leaves of four fig varieties (Fassi, Ghouddane, Nabout, and Ounq Hmam) grown in three different locations (Chefchaouen, Taounate and Taza) in northern Morocco. The combined effects of location, variety, and interactions were determined on chlorophyll fluorescence (Fv/Fm), SPAD index, total chlorophyll Content (ChlT), canopy temperature depression (CTD), proline content, protein content, total soluble sugar (TSS), Hydrogen peroxide (H2O2) and malondialdehyde (MDA). Significant variation was observed among varieties and locations, with the variety effect being the main source of variability. The results showed that Nabout variety exhibited the greatest photosynthetic efficiency as indicated by its elevated SPAD index, ChlT, and Fv/Fm values, and showed lower sensitivity to oxidative stress (low proline content, H2O2, and MDA levels). In contrast, Ghouddane had the highest values of oxidative stress markers. Among locations, Chefchaouen showed the highest protein, TSS, H₂O₂, and MDA levels, reflecting active metabolic adjustments and stress mitigation. These variations were confirmed by principal component analysis, which revealed a clear separation between photosynthetically efficient varieties (Nabout and Ounq Hmam) and stress-tolerant varieties (Ghouddane and Fassi). In conclusion, local varietal selection is essential for optimizing fig production in regions subject to climatic variability.