Influence of nitrogen and spacing on growth and yield of chia (Salvia hispanica) in Meru county, Kenya

Abstract

Chia (Salvia hispanica L.) is an emerging food crop in Kenya and has attracted a lot of attention due to its edible seeds and leaves. Despite its importance, Chia production is still very low due to scarce information on the agronomic management. A field experiment was conducted in the upper-midland zone Meru County, at the Meru University of Science and Technology, in two seasons (February-June 2021 and March-August 2021), to determine the influence of nitrogen fertilizer and spacing on growth and yield of Chia (Salvia hispanica L.). The experimental design was a randomized complete block design with a split plot arrangement with four nitrogen rates (0, 40, 80, 120 kg N ha^-1) as main plots and three plant spacing levels (30 cm x 15 cm, 30 cm x 30 cm, 50 cm x 50 cm) as the sub plots, replicated three times. Application of 120 kg N ha^-1 significantly increased (p≤0.05) vegetative growth and seed yield of Chia.  Chia height, number branches, stem diameter, number of leaves and total dry weight increased by 23-28%, 11-13%, 43-55%, 59-88% and 59-101%, respectively. 50 cm x 50 cm significantly increased (p≤0.05) vegetative growth. An increase of 7-8%, 27-74%, 36-45% and 73-107% was recorded in number of branches, number of leaves, stem diameter and dry weight, respectively. Chia yield per plant was significantly higher (p≤0.05) in 50 cm x 50 cm. However, when expressed per unit area, 15 cm x 30 cm significantly produced higher yields. The study recommends 120 kg N ha^-1and a 15 cm x 30 cm as the best option for Chia production in Kenya.