N, P, K fertilizer requirement level of Stevia rebaudiana Bertoni M. on latosolic soil
1986
Angkapradipta, P. (Balai Penelitian Perkebunan Bogor (Indonesia)) | Tuti-Warsito | Faturachim, P.
An NPK factorial 5 x 2 x 2 pot experiment in a greenhouse using reddish brown latosol with a basal dressing of 200 gram cowdung manure per pot of 5,5 kg soil, was conducted during the period from February to August 1983. Each pot was supplied with one Stevia seedling. Yield response was assessed in terms of the above-ground fresh and dry matter weight of the cumulative yield of three harvests. Soil and plant analysis showed the following. Cowdung manure markedly improved the fertility level of the soil. Increasing rates of nitrogen did not affect the soil-N, but had a significant positive effect on plant-N content. Soil pH as well as K2O, CaO and MgO levels in the soil were depressed by increasing rates of nitrogen. The phosphorus and potassium fertilizer increased soil P2O5 and K2O contents, but did not affect P and K contents in the plant. Only nitrogen at the third level (N2) increased significantly the above-ground fresh and dry matter production, as well as fresh weight of roots. The results of this experiment suggest that the nitrogen requirement levels based on the quadratic regression of the fresh as well as the dry matter yields of the above-ground part are respectively 0,91 gram and 0,92 gram of Urea per plant for each application. These rates are restricted to the first year of harvest only. The phosphorus and potassium fertilizer requirement levels could not be determined from the results of this experiment.
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