Inner Mongolia, a major region in China for growing sugar beet, faces challenges caused by unscientific water and fertilizer management. This mismanagement restricts the improvement of sugar beet yield and quality and exacerbates water waste and environmental pollution. This study aims to evaluate the effects of reduced water and fertilizer on the growth and physiological metabolism of sugar beet taproot. Field experiments were conducted in Ulanqab, Inner Mongolia, in 2022 and 2023, using a split-plot design with three levels each of fertilization and irrigation. The study analyzed the effects of reduced water and fertilizer treatments on fresh taproot weight, respiration rate, energy metabolism, respiratory enzyme activity, and gene expression in sugar beet taproot. It was found that a 10% reduction in fertilizer significantly increased the beet taproot fresh weight. Further research revealed that during the rapid leaf growth phase and the taproot and sugar growth period, a 10% reduction in fertilizer upregulated HK and IDH gene expression and downregulated G6PDH gene expression in the beet taproot. This increased HK and IDH activities, decreased G6PDH activity, enhanced the activity of the EMP-TCA pathway, and inhibited the PPP. Taproot weight was positively correlated with the respiration rate, ATP content, EC, and ATPase, HK, and IDH activities, thereby increasing the taproot growth rate and taproot fresh weight, with an average increase of 4.0% over two years. These findings introduce a novel method for optimizing fertilizer use, particularly beneficial in water-scarce regions. Implementing this strategy could help farmers in western Inner Mongolia and similar areas improve crop yield and sustainability. This study offers new insights into resource-efficient agricultural practices, highlighting the importance of customized fertilization strategies tailored to local environmental conditions.

Sugar beet (Beta vulgaris L.) is a crucial economic crop in northern China. Fertilizer and water waste and environmental contaminations were prevalent during sugar beet cultivation. To enhance sugar beet use efficiency and reduce the amount of water and fertilizer required in cultivation, a three-year experiment was performed. Drip fertilization was employed for irrigation and fertilization. The influence of irrigation reductions (15% and 30%) and fertilization reductions (20% and 10%) on yield, sugar content, and water and fertilizer use efficiency was evaluated. The yield of root and sugar was not significantly impacted by the 10% fertilizer and 15% reduction in irrigation relative to the conventional water and fertilizer supply treatment (CK). The yield was significantly reduced by 20% fertilizer and 30% irrigation reduction. The sugar yield was also reduced by 30% through irrigation reduction treatments. The root sugar content was increased by irrigation and fertilization reduction (except 10% fertilizer reduction treatment). Partial factor productivity (PFP) was significantly increased by fertilization reduction. The irrigation water use efficiency (WUEi) was significantly increased by irrigation reduction. Water use efficiency (WUE) and fertilizer agronomic efficiency (FAE) were increased by a 10% reduction of fertilization treatment relative to CK; the impact on FAE was more significant compared to WUE. The FAE was reduced by an irrigation reduction. The WUE was reduced by 20% through fertilization reduction treatments. The influence of each treatment on PFP, FAE, and WUEi of sugar yield was mirrored in yield, but the range was narrowed. To ensure high production and efficiency while conserving water and fertilizer during sugar beet cultivation within the test area, the optimal irrigation amount was 1041.91 to 1286.27 m³·ha⁻¹and fertilization amount was 394.04 to 408.03 kg·ha⁻¹. This investigation offers irrigation and fertilization parameters for drip fertilization of sugar beet and a theoretical foundation for the crop’s water and fertilizer use.

Northern China faces water scarcity, restricting water usage in place across Inner Mongolia’s western region. The integrated irrigation and fertilization model for sugar beet is undergoing rapid development and application in production. However, there is a concerning trend in production where the frequency of irrigation and fertilization is being increased blindly, resulting in the wastage of valuable water and fertilizer resources. Limiting water and fertilizer usage is an effective approach to improve sugar beet production efficiency. Sugar beets are a significant sugar crop in China. A split-plot design was employed to examine the impact of reducing water and fertilizer use on sucrose metabolism in sugar beet root. Our study was performed at the Ulanqab Institute of Agricultural and Forestry Sciences in Inner Mongolia from 2022 to 2023. Three levels of fertilization and irrigation were utilized. We investigated the interactions between irrigation and fertilization on sucrose accumulation in sugar beet root. We examined key enzyme activities involved in sucrose metabolism alongside their gene expression levels. The findings suggested that reducing irrigation by 15%, fertilization by 10%, or both irrigation by 15% and fertilization by 10%, increased sucrose concentrations of sugar beets compared to the control group administered conventional water and fertilizer. Over the two-year period, the average sucrose concentration increased by 0.45, 0.57, and 0.65 degrees, respectively, under each treatment. Subsequent research verified that appropriately reducing water and fertilizer can regulate the expression of enzyme genes, thus influencing enzyme activity. Moreover, due to the higher efficiency of enzyme synthesis compared to decomposition, it contributed to an increase in net enzyme activity. These findings suggest that an appropriate reduction of water and fertilizer can improve sucrose synthesis rates and increase the sucrose concentration in sugar beets, providing a theoretical basis for environmentally friendly generation and enhanced efficiency in sugar beet growth.