Evaluating the influence of pre-harvest hybrid treatments (compost manure and potassium nitrate fertilizer) on the mechanical properties of eggplant (cv. Bello) fruits

There is an urgent need for fruits enhancers due to rise in food insecurity globally. Eggplant (Solanum aethiopicum L.) fruit is one of the most widely consumed fruit in the world, and Nigeria in particular. The aim of this study was to evaluate the potential of using compost manure and potassium nitrate (KNO3) fertilizer as fruit enhancers in eggplant production. The research was carried out on Bello eggplant using seven different treatments. Apart from the control unit, compost manure was applied at the rate of 2500 and 5000 kg/ka; the KNO3 fertilizer was applied at the rate of 150 and 300 kg/ha; combined treatment of compost manure and KNO3 was applied at the rate of 2500 kg (compost) + 150 kg (KNO3) and 5000 kg (compost) + 300 kg (KNO3) per hectare. Fruits from all the treatments were harvested at peak maturity stage, and the mechanical properties determined, in accordance to international procedures. Results obtained from the mechanical test revealed that fruits produced with combined treatment had better failure force, failure energy and compressibility, compared to the control fruits, or the fruits produced with single treatment. Regarding the single treatment, the results revealed that fruits produced with compost manure had better compression properties than the fruits produced with KNO3. A failure force of 829.00 and 855.33 N were recorded in the fruits produced with compost manure at the two concentration levels respectively. Similarly, failure force of 798.33 and 831.67 N were recorded in the fruits produced with KNO3 at the two concentration levels respectively. This study results affirmed that combined treatment was better than single treatment, and the combined treatment can be used as fruits enhancer. Results obtained from this study can also be used to design and develop eggplant fruit harvesting, handling and packaging machines.