International Journal of Horticulture, 2024, Vol.14, No.6, 368-380 http://hortherbpublisher.com/index.php/ijh 371 Tissue culture or micropropagation is a more advanced method that allows for the large-scale production of uniform and disease-free seedlings. This technique is particularly successful in producing high-quality seedlings and has a high survival rate during the acclimatization process (Abdolinejad et al., 2020; Hong et al., 2020; Ling et al., 2022). For example, Abdolinejad et al. (2020) employed various tissue culture techniques, including thin cell layer (TCL) technology and somatic embryogenesis. These techniques not only improved the regeneration efficiency of figs but also confirmed the genetic consistency of the regenerated plants through flow cytometry and ISSR markers. 3.3 Seed reproduction: pollination and fruit set Ficus carica has a unique reproductive strategy that involves a highly specialized mutualistic relationship with the figwasp Blastophaga psenes. This complex interaction is essential for the successful production of seeds and the formation of viable fruits. The fig wasp enters the syconium, a specialized inflorescence structure unique to figs, through a small opening called the ostiole. Inside the syconium, the wasp pollinates the short-styled female flowers while also laying eggs in some of them (Falistocco, 2020). The pollinated flowers develop into seeds, while those in which eggs are laid form galls that provide a habitat for the developing wasp larvae. This intricate pollination process is crucial for the reproductive success of Ficus carica, especially for wild-type figs, also known as caprifigs, as they require pollination for seed development (Figure 1) (Proffit et al., 2020). Although many edible fig varieties produce parthenocarpic fruits, which develop without pollination or fertilization, pollination can still enhance the quality and size of the fruit. Pollinated figs tend to be fuller and have a better flavor compared to non-pollinated ones. The success of pollination is influenced by several factors, including the population of Blastophaga psenes, climatic conditions, and the synchronization between the flowering of fig trees and the life cycle of the wasps. Favorable environmental conditions, such as moderate temperatures and stable humidity levels, promote wasp activity and increase the likelihood of successful pollination. In contrast, extreme weather conditions can disrupt this delicate balance, leading to reduced seed set and fruit quality (Boliani et al., 2019; Zolfaghari et al., 2019). 4 Ecological Adaptability of Ficus caricain Arid and Barren Environments 4.1 Drought resistance mechanisms Ficus carica exhibits several structural and physiological adaptations to withstand drought conditions. One key mechanism is leaf abscission, which reduces water loss by shedding leaves during periods of water stress. This was observed in Tunisian fig cultivars, where drought stress led to significant decreases in photosynthesis rate, stomatal conductance, and transpiration rate, along with increased leaf temperature and massive leaf abscission. Upon rehydration, these plants showed recovery in photosynthetic function and vegetative growth, indicating a robust drought avoidance strategy (Ammar et al., 2020). Additionally, Abdolinejad and Shekafandeh (2022) found that tetraploid figs exhibited superior performance in various physiological and biochemical defense mechanisms compared to diploids. The experiment utilized different concentrations of polyethylene glycol (PEG) to simulate drought stress, revealing that tetraploid genotypes were able to maintain higher relative water content (RWC) and lower ion leakage under high-intensity (15%-25% PEG) stress, whereas diploid genotypes showed a significant decrease in survival rate at 15% PEG stress (Figure 2). These tetraploids maintained higher RWC and enhanced osmotic adjustment by increasing the levels of stress response hormones and osmolytes, such as proline and glycine betaine, thereby sustaining cell turgor and protecting cellular structures under drought conditions (Abdolinejad and Shekafandeh, 2022). 4.2 Water use efficiency Ficus carica demonstrates efficient water use strategies to survive in low-water environments. Under drought stress, the fig tree adjusts its physiological processes to optimize water use efficiency (WUE). For instance, drought-stressed fig plants show reduced stomatal conductance and transpiration rates, which help in conserving water. Elevated CO2 levels further enhance WUE by improving photosynthetic rates and reducing water loss through stomata. This dual response to water stress and elevated CO2 helps Ficus carica maintain its physiological
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