Emitter depth variation in the sub-surface drip irrigation system based on emitters with flannel cloth on the growth quality of spinach (Amaranthus sp.)

Abstract

Soil water availability plays an important role in plant growth; therefore, an irrigation system that maintains soil moisture efficiently is required. Subsurface drip irrigation is a potential method to improve water use efficiency and maintain moisture in the root zone. This study aimed to analyze the effects of emitter depth variation on soil moisture, water use efficiency, and spinach (Amaranthus sp.) growth. The experiment was conducted using three emitter depths: 3 cm, 6 cm, and 9 cm below the soil surface. Observed parameters included soil moisture, water use efficiency, plant height, number of leaves, and leaf width. The results showed that a 6 cm emitter depth produced stable soil moisture in the root zone and the highest water-use efficiency (87.20%). The best plant growth was also observed at 6 cm depth, with an average height of 17.4 cm and 20 leaves. The 9 cm depth resulted in lower growth performance due to less optimal water distribution. In conclusion, a 6 cm emitter depth is most effective for maintaining soil moisture, improving water-use efficiency, and supporting optimal spinach growth.