Growth Responses of Kenaf (Hibiscus cannabinus L.) to Irrigation and Fertilization in Saemangeum Reclaimed Land

Abstract

Irrigation is required to control salinity and drought stress but it is difficult to secure water resources with good quality in reclaimed lands. This study was conducted to 1) examine applicability of river water as irrigation resources, and 2) estimate suitable irrigation amount and nitrogen fertilization rate (NFR) according to root zone condition for kenaf in the Saemangeum reclaimed land. Under the limited rooting depth, kenaf was cultivated with four irrigation levels (600, 800, 1,000 and 1,200 mm) and four NFRs (0, 36, 84 and 120 N kg ha -1 ) in 2020. With the extended rooting depth, kenaf was subjected to same irrigation treatments to those in 2020 and three NFRs (0, 60 and 120 N kg ha -1 ). The Total organic carbon (TOC) and Biochemical oxygen demand (BOD) of river water slightly exceeded the agricultural water quality standard in some periods on 2020 and 2021, but water quality generally met the standard. Kenaf growth and yield increased with irrigation of 1,000 mm, but decreased in 1,200 mm compared to those in 1,000 mm under the limited rooting condition. With extended root zone, kenaf yield continuously increased with irrigation. At irrigation of 1,200 mm, kenaf yield increased with increasing NFR. Consequently, the nitrogen fertilizer effect was amplified as soil moisture was sufficiently supplied through irrigation. It is concluded that the amount of water and fertilizer should be determined according to the environmental conditions in the Saemangeum reclaimed land.

Optimum Application Rate of Nitrogen, Phosphorus, and Potassium Fertilizers for Kenaf (Hibiscus cannabinus L.) Yield and Soil Chemical Properties in a Reclaimed Paddy Soil: A Pot Experiment

“…수분관리 기술에 대한 연구가 이루어지고는 있다(Kang et al, 2021(Kang et al, , 2023Ock et al, 2022). 하지만 여전히 남부지역 간척지에서 무기질 비료 시용에 따른 케나프 생육 특성 및 바이오매스 생산성, 토양화학성을 조사한 연구는 부족한 실정이며, 최적 시비량 산정을 비롯한 최적 생육 조건 확립을 위한 충분한 기초 자료 구축이 필요한 실정이다.…”