Muchamad Angga Febrian, Humizda Izza Maharani Is, Aditya Cindy Cantika, Ahmad Mubarok, Sundahri*)
Study Program of Agronomy, Faculty of Agriculture, The University of Jember
*) Corresponding author: Sundahri.faparta@unej.ac.id
The interplay between silica application, water stress, and the growth of soybean crops in dryland conditions presents a compelling area of research in agronomy. Soybeans (Glycine max) are significantly affected by environmental stresses, particularly drought, which can lead to drastic reductions in yield and productivity. Various studies have documented the physiological responses of soybean to water stress, emphasizing the need for effective agricultural practices that could alleviate these effects.
Water stress is a primary deterrent to soybean yield. Drought stress can reduce soybean seed yield by as much as 50% under adverse conditions, as shown in greenhouse studies where soybean seed yield was significantly affected by drought stress (He et al., 2020; . Such reductions occur because water scarcity inhibits crucial physiological processes, including photosynthesis, transpiration, and nutrient uptake---factors essential for optimal growth and development (Corbellini et al., 2024; , Hossain et al., 2024). Water stress primarily affects the flowering and pod-setting stages of soybean, which are critical for determining yield (Zou et al., 2020).
To mitigate the adverse effects of water stress, several ameliorative approaches have been proposed, including the application of silica and other bio-stimulants (Silva et al., 2022; . Somanagouda et al., 2024). Silica has been shown to enhance drought resistance in various crops, including soybean. The application of silica can improve leaf water retention, increase chlorophyll content, and enhance the overall photosynthetic rate of plants under stress conditions (Rauf et al., 2023). Additionally, the incorporation of biochar along with silica has been found to enhance soil moisture retention and nutrient availability, which are crucial for drought resilience in soybean crops (Zhang et al., 2020; , Nawaz et al., 2022).
Research indicates that plants subjected to combined water stress and silica application exhibit improved physiological responses compared to those not treated with silica. For instance, these stress conditions trigger a range of physiological adaptations in soybean, such as increased root length and enhanced nutrient uptake efficiency, which are pivotal for coping with water deficiency (Gong et al., 2023; , Gao et al., 2020). Studies underscore that the synergistic effects of soil amendments---like silica and biochar---can lead to significant enhancements in water use efficiency and improvements in growth metrics such as plant height, biomass, and seed yield in soybean (Jabborova et al., 2022).
Moreover, the beneficial effects of silica extend beyond water stress mitigation. Evidence suggests that it can enhance the plant's nutrient absorption capabilities and improve resistance to various environmental stressors (Chen et al., 2023). The mechanisms behind these improvements are believed to involve increased root development and enhanced physiological traits, such as stomatal conductance and transpiration efficiency (Anda et al., 2021).
It is equally important to consider the variability among soybean genotypes in response to both water stress and silica application. Certain cultivars exhibit inherent drought resistance that can be further augmented through proper soil amendments, demonstrating differential responses to stress conditions (Tavares et al., 2022). Identifying and cultivating such genotypes is essential for developing resilient cropping systems capable of thriving under conditions exacerbated by climate change (Sun et al., 2022).
In addition to soil amendments and silica, the timing of irrigation and water management practices also play a crucial role in ensuring soybean's drought resilience. Specific irrigation strategies during critical growth stages can improve water uptake and enhance yield (He et al., 2020; , Bryant et al., 2022). Integrating these agronomic practices could lead to more sustainable soybean production systems in arid and semi-arid regions, where water scarcity remains a prevalent challenge (Haarhoff & Swanepoel, 2021).
As climate change continues to bring more unpredictable weather patterns, research into the interaction of various stressors and the development of adaptive strategies is paramount. Studies have suggested that the combination of abiotic stress factors such as high temperature, elevated CO2 levels, and water stress may have synergistic negative effects on soybean yield, making it crucial to adopt holistic management practices that address multiple stressors simultaneously (Singh et al., 2021).
