Fertigation based on a nutrient balance model for cassava production in two different textured soils

Abstract

Appropriate rate and frequency of fertigation is important for the production of cassava (Manihot esculenta Crantz). The present study investigated the effects of different fertigation rates and frequencies on cassava production under a drip irrigation system in sandy clay loam (SCL) and loamy sand (LS) soils. The study was undertaken in the 2014/15 and 2015/16 growing seasons and the treatments were designed to compare two fertilization methods and two fertilizer rates. The results show that while using the same amount of fertilizer, fertigation resulted in higher leaf nutrient content, storage root yield, and fertilizer nutrient use efficiency in comparison to soil fertilizer application. Fertigation based on nutrient balance model (F-NB) significantly increased the leaf N content, storage root yield, starch content, and harvest index compared to fertigation based on Department of Agriculture recommendations (F-DOA). Yield and starch content for the same treatments in SCL soil were higher than those in LS soil. In the 2016/17 growing season, the treatments were designed to compare two fertilization methods, two fertilizer rates, and two fertigation frequencies. F-NB with a high frequency (F-NBH) produced the highest storage root yield, while the lowest yield was produced by the soil fertilizer application based on DOA (S-DOA) in both soils. The nitrogen (N), phosphorus (P), and potassium (K) distribution in the plant parts were mostly concentrated in the stems and storage roots, while F-NBH increased the nutrient uptake and increased N, P, and K concentrations in the cassava storage root, and enhanced the yield and starch content.

Keywords

• storage root yield
• nutrient uptake
• fertigation rate
• fertigation frequency