IJH_2024v14n6

International Journal of Horticulture, 2024, Vol.14, No.6, 355-367 http://hortherbpublisher.com/index.php/ijh 357 hormone regulation and antioxidant enzyme activity, helping the plant adapt to adverse conditions. Advances in breeding and biotechnology have further improved rapeseed’s stress resistance. For instance, breeding programs selecting for specific traits have successfully enhanced stress tolerance, while modern biotechnological approaches, such as gene editing, offer promising avenues for increasing rapeseed’s resilience to challenging environmental factors (Raza, 2020; Raboanatahiry et al., 2022). 2.3 Economic importance Rapeseed holds substantial economic importance due to its versatile applications. It is the second most important oil crop globally, following soybean, and its oil is widely used for cooking, industrial purposes, and as a feedstock for biodiesel production (Raboanatahiry et al., 2022). The economic value of rapeseed is also linked to its by-products, such as meal, which is a high-protein animal feed. The economic value of rapeseed also relates to its by-products, such as high-protein rapeseed meal, which is an important animal feed. With the advancement of biorefining technology, rapeseed meal is now also regarded as a raw material for producing bio-based, high-value-added molecules, including antioxidants and protein isolates, opening up more applications and enhancing its economic worth (Di Lena et al., 2021). Studies further indicate that polyphenolic compounds in rapeseed meal exhibit strong antioxidant properties, making them suitable for applications in the food or pharmaceutical sectors (Laguna et al., 2018). In regions like China, rapeseed cultivation is integral to food security and rural livelihoods, with socio-economic factors like rural electricity consumption and agricultural mechanization playing significant roles in yield enhancement (Liang et al., 2023). The development of high-yielding and disease-resistant rapeseed varieties through advanced breeding techniques, including QTL analysis and GWAS, further underscores its economic significance (Khan et al., 2021). The optimization of agronomic practices, such as weed control and drainage, can significantly narrow the yield gap, thereby boosting the economic returns from rapeseed cultivation (Zhang et al., 2020). 3 Influence of Climatic Conditions on Rapeseed Yield and Quality 3.1 The impact of temperature on the growth cycle and oil content Temperature significantly affects the germination rate of rapeseed seeds and the vigor of seedlings. A study compared the effects of 21/18 °C (control temperature, CT), 28/18 °C (moderate temperature, MT), and 34/18 °C (high temperature, HT) on seed development in rapeseed (Mácová et al., 2022). The results showed that under higher temperature conditions, seed viability and germination rates in rapeseed significantly decreased, while abnormalities in embryo development intensified. Further analysis revealed that early-stage embryonic abnormalities persisted into the seedling stage, with high temperatures impacting embryo structure and subsequently diminishing the growth quality of both seeds and seedlings (Figure 1). Low-temperature conditions (e.g., 8 °C or lower) significantly inhibit germination rate, as well as root and shoot growth in rapeseed. Genetic studies indicate that under low-temperature stress, rapeseed seeds activate a gene expression regulatory network involving transcription factors such as WRKY, bZIP, and MYB to manage oxidative stress induced by cold, maintain cell wall relaxation, and support embryo expansion, which is critical for improving germination rates in low-temperature environments (Luo et al., 2019; Korniychuk and Yurchuk, 2023). Temperature also significantly affects oil synthesis and composition in rapeseed. High temperatures during the seed development phase can lead to reduced oil content and altered fatty acid composition, negatively impacting oil quality (Mácová et al., 2022). Studies have shown that cooler temperatures during seed development are associated with higher oil content and better oil quality (Marjanović-Jeromela et al., 2019). The interaction between temperature and other climatic factors, such as precipitation and humidity, further influences oil synthesis, necessitating a comprehensive understanding of these dynamics for optimal oil production (Marjanović-Jeromela et al., 2019; Jannat et al., 2022).

RkJQdWJsaXNoZXIy MjQ4ODYzNA==