An experiment was carried out to investigate the effects of different mineral fertilizers on mineral contents in turmeric rhizomes and soil enzyme activities and soil properties under field conditions in Uzbekistan. The present study is the first report on the impact of mineral fertilizers in turmeric rhizomes and soil enzymes and soil properties in Uzbekistan. The experiment was carried out with four treatments: T1—Control, T2—N75P50K50 kg/ha, T3—N125P100K100 kg/ha, and T4—N100P75K75 + B3Zn6Fe6 kg/ha. Turmeric rhizomes and soil samples were collected from field experiments at the Surkhandarya scientific experimental station of the vegetable, melon crops and potato research institute, Surkhandarya, Uzbekistan. The data showed that T3—the NPK (125:100:100 kg/ha) and T4—the NPK + BZnFe (100:75:75:3:6:6 kg/ha) treatments significantly enhanced K content by 27–21%, Ca content by 43–38%, and P content by 54–17% in turmeric rhizomes as compared to control without fertilizer. A maximum of turmeric rhizome microelements content was recorded with T4, which also resulted in improved Fe, Zn, Cu, Cr, and Mo contents in turmeric rhizomes and mineral contents of soil compared to other treatments. This treatment significantly enhanced active P content by 34%, active K content by 25%, total P content by 62%, total K content by 14%, and the activities of soil urease, invertase, catalase, and phosphatase over those in the control. The present study results suggest that the application of NPK + BZnFe (100:75:75:3:6:6 kg/ha) improves macro and micronutrient contents in turmeric rhizomes and activities of soil enzymes and physicochemical properties of soil.

Ginger is rich in different chemical compounds such as phenolic compounds, terpenes, polysaccharides, lipids, organic acids, minerals, and vitamins. The present study investigated the effect of mineral fertilizers on the content of mineral elements in the rhizomes of Zingiber officinale Roscoe, soil enzymes activity, and soil properties in Surkhandarya Region, Uzbekistan. To the best of our knowledge, the present study is the first in Uzbekistan to investigate the mineral elements of ginger rhizome inhabiting Termez district, Surkhandarya region. A Field experiment was conducted at the Surkhandarya experimental station research Institute. Four treatments have been studied (Control with no fertilizers (T-1), N₇₅P₅₀K₅₀ kg/ha (T-2), N₁₂₅P₁₀₀K₁₀₀ kg/ha (T-3) and N₁₀₀P₇₅K₇₅ + B₃Zn₆Fe₆ kg/ha (T-4)). Results showed that T-4 treatment significantly increased ginger rhizome K, Ca, P, Mg, Fe, Na, Mn, Zn, Si, Li, and V content as compared to all other treatments and control. T-3 treatment significantly increased Mo, Ga, and Ag content in comparison to other treatments. Soil enzymes showed a significant increase for all treatments against control, while T-4 treatment has recorded the highest enzyme activity in comparison to all other treatments in urease, invertase, and catalase content. Soil chemical properties have significantly changed for all treatments against the non-cultivated soil and the zero fertilizers plantation with variation among different treatments. Results showed that ginger root is rich in minerals and can be used as a great potential for nutritional supplements and soil enrichment. This study suggest that combination of macro-microelements have the potential to increase the content of mineral elements in the rhizomes of ginger in field conditions.

A mineral fertiliser has positive effects in improving turmeric nutrients, soil enzymes and soil properties. The aim of this research was to study the effect of mineral fertilisers on the content of mineral elements in turmeric rhizome, soil enzymes activity and soil properties in the Tashkent Region, Uzbekistan. For the first time in Uzbekistan, the turmeric rhizome was cultivated to study the mineral elements present in the rhizome. A microplot experiment was conducted with four treatments including T1 (Control), T2 (N₇₅P₅₀K₅₀ kg/ha), T3 (N₁₂₅P₁₀₀K₁₀₀ kg/ha) and T4 (N₁₀₀P₇₅K₇₅ + B₃Zn₆Fe₆ kg/ha) and turmeric rhizome, which were collected for observation along with the soil samples. The analyses indicated that the NPK + BZnFe (100:75:75:3:6:6 kg/ha) treatment significantly improved minerals such as K, Ca, P, Mg and Na contents rhizome as compared to the control without fertiliser. Likewise, the maximum quantity of micronutrient content viz., Fe, Mn, Zn, Cu, Cr and Si was also recorded in turmeric rhizome treated with NPK + BZnFe (125:100:100:3:6:6 kg/ha). It showed an increase in these micronutrients in the rhizome compared to the control, followed by a low rate of NPK (75:50:50 kg/ha). The highest content in terms of total N, P, K content, humus, active phosphorus, potassium, and enzymes activity was also observed in soil with the treatment of mineral fertiliser viz., NPK + BznFe (100:75:75:3:6:6 kg/ha), which enhanced soil nutrient and enzyme activity. The NPK + BznFe (100:75:75:3:6:6 kg/ha) treatment significantly increased the active N content by 40%, total P content by 38% and total K content by 22% in comparison to the control without mineral fertiliser. Overall, it was found that NPK + BznFe (100:75:75:3:6:6 kg/ha) was significantly valuable for enhancing the total nitrogen, phosphorus, and potassium levels in the soil compared to control, which is useful for improving soil health in terms of soil enzyme and soil nutrients. Additionally, the micronutrients in turmeric rhizome were significantly enhanced when using this combination of fertiliser applications [NPK + BznFe (100:75:75:3:6:6 kg/ha)]. Therefore, this present study revealed that the NPK+BznFe (100:75:75:3:6:6 kg/ha) could produce the most significant yield of high-quality turmeric plants and improve soil properties in Uzbek soil–climate conditions.