Cotton Genomics and Genetics 2025, Vol.16, No.2, 72-79 http://cropscipublisher.com/index.php/cgg 74 3.2 Enhancement of boll set and retention Micronutrients significantly influence boll set and retention, which are vital for improving cotton yield and fiber quality. Boron application has been shown to improve boll retention and increase the number of bolls per plant, which directly contributes to higher fiber yield (Abbas et al., 2023). The foliar application of boron and silicon, either individually or in combination, has been found to enhance boll retention and seed cotton production, indicating their role in stabilizing boll set under various environmental conditions (Abbas et al., 2022). 3.3 Impact on fiber fineness, strength, and length The application of micronutrients such as boron and silicon has a profound impact on fiber fineness, strength, and length. Studies have demonstrated that the combined application of boron and silicon improves fiber length and tensile strength, while also reducing short fiber content, thereby enhancing overall fiber quality (De Souza Júnior et al., 2022). Boron application alone has been shown to improve fiber length and uniformity, contributing to better fiber quality traits (Wahid et al., 2020). Moreover, the use of biostimulants and micronutrient management strategies can lead to improvements in fiber characteristics such as length uniformity, micronaire, and strength (Silva et al., 2016). 4 Strategies for Effective Micronutrient Management 4.1 Soil-based management techniques Soil-based management techniques for micronutrient management in cotton involve the application of essential nutrients directly to the soil to enhance plant growth and fiber quality. Boron (B) is a critical micronutrient for cotton, especially in calcareous saline soils where deficiencies are common. Soil application of boron has been shown to significantly improve growth, yield, and fiber quality traits. For instance, applying 2.60 mg/kg of boron to the soil improved plant height, leaf area, and boll characteristics, leading to enhanced seed cotton yield and fiber quality in the CIM-600 cotton cultivar (Atique-Ur-Rehman et al., 2020). This approach ensures that the micronutrients are available throughout the plant's growth stages, particularly during boll formation, which is crucial for fiber development. 4.2 Foliar application approaches Foliar application is a widely used strategy for delivering micronutrients directly to the plant leaves, allowing for rapid absorption and utilization. This method is particularly effective for micronutrients like boron and silicon, which play vital roles in improving cotton fiber quality. Studies have demonstrated that foliar application of boron and silicon, either individually or in combination, can enhance fiber length, strength, and uniformity. For example, a combined foliar application of 4.0 mM silicon and 1.0 mM boron resulted in significant improvements in fiber quality traits such as ginning out turn and fiber uniformity (De Souza Júnior et al., 2022; Abbas et al., 2023). Additionally, foliar application of mepiquat chloride and nitrogen has been shown to improve boll weight, seed cotton yield, and fiber quality, highlighting the effectiveness of foliar nutrition in optimizing cotton production (Abbas et al., 2022). 4.3 Integrated nutrient management (INM) Integrated nutrient management (INM) combines soil and foliar applications to optimize nutrient availability and improve cotton fiber quality. This approach involves the strategic use of both soil-applied and foliar-applied nutrients to address deficiencies and enhance plant growth. For instance, combining soil application of potassium with foliar sprays of potassium nitrate has been shown to significantly improve plant morphology, seed cotton yield, and boll characteristics (Tariq et al., 2018). INM practices also include the use of nano-calcium and potassium humate foliar sprays, which have been found to enhance growth, yield, and fiber quality in cotton grown on alluvial non-saline soils (Rabeh and Elsokkary, 2022). By integrating various nutrient management strategies, INM aims to maximize the efficiency of nutrient use, leading to improved cotton productivity and fiber quality. 5 Challenges and Knowledge Gaps in Micronutrient Research 5.1 Variability in soil and climatic conditions The effectiveness of micronutrient management in cotton production is significantly influenced by the variability in soil and climatic conditions. Micronutrients like boron and silicon are essential for cotton growth, but their
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