Growth response of different oil palm seedling parentage towards chemical fertilizer treatment

Abstract

Oil palm (Elaeis guineensis) requires a sufficient amount of chemical fertilizer to sustain their growth and development. To date, many oil palm varieties are available commercially. These varieties may experience insufficient or excessive fertilization as their specific nitrogen and potassium requirements are not fully elucidated. This research aimed to determine the effects of different nitrogen-potassium (NK) fertilizer levels on oil palm morphological characteristics, foliar nutrient content (FNC) and nitrate reductase (NR) activity of six oil palm seedlings of different parentage. Oil palm progenies designated as A-F was planted at the test plots and supplied with three NK fertilizer levels designated as T0 (0 kg Ammonium Sulphate (AS) and 0 kg Muriate of Potash (MoP) per palm), T1 (2.7 kg AS and 1.75 kg MoP per palm) and T2 (5.4 kg AS and 3.5 kg MoP per palm). Our findings indicated minimal impact of fertilizer application on oil palm growth rate. A significant (p<0.05) increase was observed in foliar nitrogen and potassium content from T1 fertilization with an average of 28% and 32%. Whereas, T2 caused only a small overall increase of 5% and 7%, respectively. Similar NR activity was recorded in most of the seedlings showing a reduced activity at the average of 18% when treated with T1 while drastically elevated when treated with T2 with a 41% overall increase. The similarity in parentage of each oil palm seedling plays a significant role in the overall reaction of seedlings towards fertilization. Although fertilization may not have a significant observable impact towards growth and foliar nutrient content, a significant response can be seen in the nitrate reductase reaction of the seedlings. Overall, the study indicates a slight favour towards T1 treatment based on the overall response of the seedlings.