Crop productivity and nutrient use efficiency of ramie (Boehmeria nivea L.) under variable NPK fertilization levels

Ramie has been cultivated worldwide for centuries and is valued for its use in food and fiber production.However, due to the lack of established standards for ramie fertilizer usage, farmers rely on their experience for fertilizer application.This study evaluated productivity and fertilizer use efficiency based on various fertilizer levels to establish standards for fertilizer application in ramie cultivation fields.The experiment was conducted in the ramine farm of Yeonggwang-gun, Jeollanam-do from 2021 to 2022.Fertilizers were applied at 0.0, 0.5, 1.0, 1.5, and 2.0 times based on N-P 2 O 5 -K 2 O = 350-140-350 kg ha -1 , and the fertilization rates were divided into a basal application and four times top-dressings after each harvest.Nitrogen fertilizations were strongly responsible for leaf nitrogen (SPAD value) and yield.Fertilizer use efficiency was significantly highest at the 0.5 times NPK level.Based on the yield response from five harvests of ramie leaves, the optimal fertilizer amount for maximum yield was N 525 kg ha -1 , P 2 O 5 140 kg ha -1 , and K 2 O 525 kg ha -1 .Further research is necessary to establish a manual for customized fertilization being fitted to variable soil nutrient levels.