Growth and Yield Response of Groundnut (Arachis hypogea L.) to Inorganic Fertilisers at Luyengo, Middleveld of Eswatini

Groundnut is an important food and cash crop for smallholder farmers in Eswatini. However, its yield is very low partly due to poor soil fertility particularly calcium and phosphorus deficiencies associated with soil acidity. Thus, a field experiment was conducted to determine the effects of different inorganic fertiliser types on growth and yield of groundnut. The treatments were: a control with no fertiliser, [2:3:2 (22) at 300 kg ha-1], single superphosphate (100 kg ha-1), calcium nitrate (120 kg ha-1) and a combination of calcium nitrate (120 kg ha-1) and single superphosphate (100 kg ha-1). A randomised complete block design (RCBD) with three replications was used. Results showed highly significant (p<0.01) differences among the fertiliser types on most of the growth parameters recorded. At 90% flowering, significantly highest number of leaves per plant (48.3), the tallest plant (42.17 cm), the highest canopy width (41.47 cm), the highest number of branches per plant (6.57) and plant dry biomass per plant (20.6 g) were recorded for treatments with calcium nitrate followed by the application of combination of calcium nitrate and single superphosphate. Similarly, most of the yield components and yield were significantly (p<0.05) affected by the fertiliser types. Significantly highest numbers of total pods per plant (28.8), mature pods per plant (26.9), dry pod yield (950.6 kg ha-1), hundred seed mass (82.8 g), shelling percentage (70.6) and seed yield (671.6 kg ha-1) were recorded from a combination of calcium nitrate and single superphosphate fertiliser. Thus, combined application of 120 kg ha-1 calcium nitrate and 100 kg ha-1 single superphosphate fertilisers can be used to increase the productivity of groundnut in the study area.