チッソ、リンおよびカリウム肥料がベニバナボロギクの生長形質に及ぼす影響

摘要

Redflower ragleaf (Crassocephalum crepidioides) is a weed as well as a functional vegetable in tropical and subtropical regions of the world. The experiment was conducted to evaluate fertilizer effects on growth characteristics of redflower ragleaf. The treatments were nitrogen (N), phosphorus (P), potassium (K), nitrogen plus phosphorus (NP), nitrogen plus potassium (NK), phosphorus plus potassium (PK), nitrogen plus phosphorus plus potassium (NPK) and control (Con，no fertilizer). Nitrogen, P and K were applied at 200 (1.0g/pot), 100 (O.5g/pot) and 100 kg/ha (0.5g/pot), respectively according to the experiment design. Redflower ragleaf grown with the application of N, NP, NK and NPK was greener, and had higher SPAD value than the plants grown with the P, K and PK. Leaf defoliation naturally started earlier in the plants grown without N application. Plant height, leaf number and branch number were highest in the plants grown with the NPK followed by NK or N. The plants grown without N application resulted in earlier flowering. Fresh and dry weight of the plants was the highest when grown with the NPK followed by NK and N. Phosphorous and K applied separately or together did not show any positive effect on growth parameters, fresh weight and dry weight of the plant, but showed positive effect when applied with the combination of N. Combined application of N, P and K resulted in the best effect on all growth parameters, fresh weight and dry weight of redflower ragleaf.