QUEFTS Model, a Tool for Site-specific Nutrient Management of Crops: A Review

The QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils) model is a valuable tool for developing location-specific management of macronutrients such as N, P, and K to attain higher yields. A review analysis is conducted to understand the applicability of the QUEFTS model in developing site-specific nutrient management (SSNM) for different crops. A total of 33 published articles are available for the QUEFTS model for different crops across the world. The SSNM is available for rice, wheat, maize, potato, tropical tuber crops (cassava, sweet potato, elephant foot yam, taro, and yam), peanut, watermelon, soybean, radish, tea, sweet potato, elephant foot yam, yam, and taro in different countries using the QUEFTS model, and it is discussed in this review. The maximum values of accumulation and dilution of N, P, and K; the balanced nutrient requirements to produce 1000 kg of crop yield; and their internal efficiencies are discussed in this review paper. The review shows that the QUEFTS model parameters derived for rice, wheat, and maize can be directly adapted to different environmental conditions. The data available for potato demand further refinement of the model for its general application irrespective of the agro-climatic conditions. The two sets of data available for cassava are similar and can use the same model parameters for further studies for nutrient management. Single set of data for other crops shows the necessity for more studies to increase their production. The modeled values for different crops presented in this review can further assist the decision-makers in scheduling fertilizer applications for the respective crops, reducing fertilizer and economic losses, and maintaining soil quality. Thus, QUEFTS can be widely used as a simple model to recommend nutrient management practices. However, the QUEFTS model considers only the mean meteorological parameters irrespective of their daily variations. It also considers the soil as a homogeneous medium, which influences the crop yield estimation, which needs to be addressed among agricultural researchers. Therefore, further modifications are also needed for QUEFTS to incorporate different agro-climatic and management conditions and different interactive processes, including other micronutrients, irrigation practices, and sub-soil properties as this model assumes that nutrients are the only limiting factors in crop yield. This review also demands the necessity to focus on the nutrient management of other food crops to ensure food security.