Bioscience Evidence 2024, Vol.14, No.6, 281-292 http://bioscipublisher.com/index.php/be 285 The reproductive phase of dragon fruit includes the flowering and fruiting periods. Flowering is induced by specific environmental signals, and the development of flowers leads to fruit production (Mallik et al., 2018). For instance, a study on red-fleshed pitaya ‘Da Hong’ (Hylocereus polyrhizus) found that high-temperature treatment (40/30 ℃) significantly suppressed fruit development, resulting in a substantial decrease in fruit set, seed weight, and fruit weight (Chu and Chang, 2020). The reproductive success of dragon fruit is also influenced by various factors, including pollination mechanisms and the plant's genetic characteristics (Abirami et al., 2021). This phase is crucial for the yield and quality of the fruit. 4.2 Flowering physiology Floral induction in dragon fruit is triggered by environmental factors such as temperature and photoperiod. The development of flowers involves a series of physiological changes that prepare the plant for reproduction. The timing and intensity of flowering can vary among different Hylocereus species, influenced by their genetic makeup and environmental conditions (Mallik et al., 2018). Pollination in dragon fruit is primarily achieved through nocturnal pollinators such as bats and moths. Successful pollination is essential for fruit set and development. The reproductive success of dragon fruit can be affected by the availability of pollinators and the compatibility of pollen and stigma. Genetic variations among Hylocereus species can also influence pollination efficiency and fruit production (Ador et al., 2024). Several factors can affect the flowering time and intensity of dragon fruit, including temperature, light, and water availability. Stress conditions such as drought or nutrient deficiency can delay flowering or reduce the number of flowers produced. Understanding these factors is crucial for optimizing flowering and maximizing fruit yield (Abirami et al., 2021). 4.3 Fruit development and maturation Fruit development in dragon fruit involves two main stages: cell division and cell enlargement. During the initial stage, rapid cell division occurs, leading to the formation of the fruit structure. This is followed by cell enlargement, where the fruit increases in size and accumulates nutrients. Morphological traits such as fruit and pulp weight, as well as the color of the peel and pulp, are important indicators of fruit development (Trong et al., 2022). Ripening of dragon fruit involves several physiological changes, including the accumulation of sugars, acids, and pigments. These changes contribute to the fruit's flavor, color, and nutritional content. The antioxidant potential of dragon fruit is higher in the peel than in the pulp, with significant variations in phenol and flavonoid content among different Hylocereus species (Abirami et al., 2021). Fruit quality and yield in dragon fruit are influenced by genetic, environmental, and management factors. Xu et al. (2024) found that spraying 100 ppm gibberellin, 10 ppm forchlorfenuron, and 1 000 ppm slow-release nitrogen fertilizer during the first fruit expansion period can extend the fruit-bearing period to 40 days and increase the soluble solids content to 21.5% (Table 1). Effective management practices, including pest and disease control, are essential for optimizing fruit yield and quality (Abirami et al., 2021; Wonglom et al., 2023; Zhao and Huang, 2023). By understanding the growth cycle and developmental physiology of dragon fruit, researchers and growers can implement strategies to enhance fruit production and quality, ensuring the sustainability and profitability of this important tropical fruit crop. 5 Environmental Response Mechanisms of Hylocereus spp. 5.1 Response to light intensity Hylocereus spp. exhibit a remarkable ability to adapt to varying light conditions, which is crucial for their survival and productivity. As a member of the Cactaceae family, dragon fruit plants are well-suited to thrive in high-light environments (Abirami et al., 2021; Kakade et al., 2022). Their stems, which serve as the primary photosynthetic organ, contain a thick waxy cuticle and sunken stomata, which help reduce water loss under intense light conditions. However, excessive light exposure can lead to photoinhibition and chlorophyll degradation, impacting photosynthetic efficiency. To counteract this, Hylocereus spp. activate photoprotective mechanisms such as the
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