RT Journal Article SR Electronic A1 Abdelaziz, Mohamed Ewis A1 Hannfy Ahmed, A. H. A1 Bekhid, R. S. A1 Pokluda, Robert T1 Response of growth patterns in sweet pepper to different NPK levels JF Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis YR 2014 VO 56 IS 1 SP 241 OP 244 DO 10.11118/actaun200856010241 UL https://acta.mendelu.cz/artkey/acu-200801-0028.php AB This work was conducted to study the effect of five NPK fertigation levels on the growth rate of sweet pepper (Capsicum annuum L. cv. Bruyo) grown under the plastic greenhouse using different growth analysis formulas. Leaf area ratio (LAR), specific leaf area (SLA), relative growth rate (RGR) and net assimilation rate (NAR) was evaluated in two periods (60-90 and 90-120 days after transplanting). The mean values of LAR, SLA, RGR and NAR tended to decrease significantly with advancing plant age in both seasons. In general, at the moderate level (34N-42P-29K / plastic house 540 m<sup>2</sup>) was found the highest significant values of LAR and SLA in the two growth periods. On the other hand, the highest values of NAR were recorded at the plants treated with the lowest NPK fertigation level (17N-21P-15K / plastic house 540 m<sup>2</sup>). However, increase of NPK fertigation doses to the moderate levels had favorable effects on LAR and SLA of sweet pepper plants.