STUDI PERTUMBUHAN DAN KANDUNGAN TIMBAL (PB) DAN CADMIUM (CD) PADA JARINGAN TANAMAN KANGKUNG YANG DIBERI PUPUK KANDANG DAN UREA

Water spinach (Ipomoea aquatica) is a highly demanded leafy vegetable in Lombok,
Indonesia, primarily used in traditional pelecing kangkung cuisine. However, its non-
selective nutrient uptake ability raises concerns regarding heavy metal accumulation,
particularly Lead (Pb) and Cadmium (Cd). This study aimed to assess the effects of manure
and urea fertilization on plant growth parameters and Pb/Cd accumulation in water
spinach tissues under flowing-irrigation conditions. A Randomized Complete Block Design
(RCBD) with four treatments (P0: no fertilizer; P1: urea 300 kg ha⁻¹; P2: manure 1 ton ha⁻¹;
P3: urea + manure) replicated three times was conducted from July to September 2025 in
Gerimax Indah Village, Narmada, West Lombok. Plant growth (stem length, shoot number,
harvest weight, total biomass) and heavy metal content in stem-leaf tissues (45 days after
planting/DAP) were measured. Results showed that P1 and P3 significantly outperformed
P0 and P2 in all growth parameters, with P1 recording the highest total harvest yield
(22.755 kg) and biomass (82.755 kg). Critically, Pb was detected only in manure-amended
plots (P2: 1.98 ppm; P3: 4.46 ppm), both exceeding the BPOM 2018 limit (0.2 ppm), while Pb
was undetectable in P0 and P1. In contrast, Cd was detected across all treatments
(0.25–0.41 ppm), all surpassing the BPOM limit (0.05 ppm), indicating irrigation water as the
primary Cd source. These findings suggest urea is effective for productivity, while
unqualified manure poses food safety risks through Pb accumulation. Cd contamination
throughout all plots highlights the urgency of routine irrigation water quality monitoring in
this cultivation area.
Keywords: cadmium, food safety, heavy metal, Ipomoea aquatica, lead, urea fertilizer