Journal Article

Growth, yield and potassium dynamics of konjac

Yusoff, Martini Mohammad, Sukor, Arina Shairah Abdul, Jaafar, Juju Nakasha, Berahim, Zulkarami, Ghani, Muhammad Najib Othman, Misran, Azizah

2026

Overview

Konjac (Amorphophallus muelleri Blume) is a tuberous species that thrives in Malaysian forests and has substantial commercial potential. Despite its importance, agronomic practices that suited with local climate is still scarce. Optimizing key agronomic practices such as shade and K rates require a clear understanding of how they affect plant growth and nutrient dynamics, and how these effects, in turn, influence yield. A field experiment was conducted and treatments of four K rates–0 (T1), 75 (T2), 150 (T3), 225 (T4) kg [ha.sup.-1] were nested in three shading rates–0%, 50%, 70%. Under each shading, each K rate was arranged in a randomized complete block design (RCBD) with four replicates. Regardless of K rates, plants under 70% shading had enhanced growth (leaflet area, petiole diameter), 33.1% more rapid K uptake and 27.9% higher corm yield (P [less than or equal to] 0.01; [alpha] = 0.05), attributed to 15.71% higher photosynthesis rates compared to plants under 50% shading. For nested effects, under 70% shading, T3 was optimum since K uptake and growth was delayed in T4 plants and the corm yield showed nonsignificant difference to T3. Under 50% shading, yield in T4 plants were significantly (P [less than or equal to] 0.01; [alpha] = 0.05) higher (46.4%) compared to T3 plants, demonstrating that under less favourable shading, higher K rate (225 kg [ha.sup.-1]) is needed to increase the yield. Soil K content across growth stages follows quadratic function and the optimum time for K fertilization which can enhance its uptake efficiency under the recommended 70% shading rate is 9-10 wk after planting.

• Publisher: Instituto de Investigaciones Agropecuarias
• Subject: Fertilizers