Activated Carbon and Phosphorus Application Influences the Growth of Continuously Replanted Asparagus (Asparagus Officinalis L.)
The influences of activated carbon (AC) and phosphorus (P) to asparagus growth were assessed under laboratory conditions. The asparagus cultivar; Gijnlim (G) of the European origin, were cultivated in different continuous replanting system. AC was incorporated into sandy soil, was amended with 15 years old root residue (RR) before the sowing of asparagus for the first, second (first replanting), third (second replanting) and fourth (third replanting) time of continuous planting. In all the planting, P was applied weekly basis at P0 (0), P1 (7.5), P2 (15.5) and P3 (22.5) mg•l−1. After third replanting, in without AC, P0 and with RR treatment, root biomass inhibited (P<0.05) by 55% and total P uptake by 52 %. Controversially, when AC was incorporated into the soil as phosphorus (P3) increased level and without RR, asparagus root biomass inhibited (P<0.05) up to 18%, total P uptake by 20 %. AC with applied P alters soil P availability and plant growth even in the presence of the RR allelopathic agent. This study provided the evidence of AC and P application will be required to improve growth and nutrient uptake by overcoming nutrient immobilization under continuous replanting
