The Development of a Model for Recommending the Application of Zinc Fertilizer in the Mediterranean Region of Central Chile

Abstract

The main aim of this study is to develop a mechanistic model of fertilization for recommending the application of zinc (Zn) fertiliser for maize based on the mass balance of Zn. The model would consider the critical Zn level for maize (Zn CL), Zn availability in the soil (Zn A) and Zn buffering capacity (Zn b). Soil samples were collected from 78 maize fields for chemical and physical characterization including measuring Zn A and Zn b. Additionally, a crop management survey was carried out in each field. The classification and regression trees method (CART) was used and relationships between Zn b and some soil properties were established, clay content being the most relevant to the model, besides soil reaction (pH) and silt content. The application of Zn fertilizer can be adequately calculated by a mechanistic model that considers Zn A , Zn b and Zn CL above that which maize crop yields do not increase. This work highlights the importance of Zn b evaluation by the incubation procedure and the extraction of available Zn by DTPA solution. As hypothesised and then demonstrated in this work, Zn b is closely related to soil pH and texture (clay and silt). Our results suggest that, in between 51 and 97% of fields examined, it would be necessary to apply Zn fertilisers to produce the maximum maize yield.

Evaluating Zinc Nutrition In Perennial Ryegrass Grown In An Andisol

“…The critical level of Zn was 0.69 mg/kg DTPA-Zn for peas grown in Indian paddy soils (Indira Sarangthem et al 2018), and is generally between 0.6 and 1.0 mg/kg in Indian soils depending on the crop (Katyal 1993, Katyal andSharma 1991). Salazar et al (2021) developed a model for recommending the application of Zn fertilizer in the Mediterranean region of central Chile. However, little is known about Zn phytoavailability in Andisols (i.e., soils derived from volcanic ash) (Hue 2004).…”