Flower abortion of pepino melon (Solanum muricatum Ait.) as influenced by NPK fertilizer rates and growing environment

Flower abortion is the detachment of flowers from the plant. A study was conducted at Egerton University, Kenya in 2018 to 2020 to investigate the effect of NPK fertilizer rates (0, 100, 200. 300 and 400 kg ha-1) on flower abortion of field and greenhouse grown pepino melons. The experiment was laid out in a randomized complete block design with three replications. Data was collected on number of flowers, number of aborted flowers, viable and non-viable pollen and in vitro pollen germination. Data were analysed using analysis of variance with the SAS statistical package. Significant means were separated using Tukey’s Honestly Significant Difference at p≤0.05. Results indicated that field grown plants supplied with 200 and 300 kg NPK ha-1 had 10.28 and 11.18 flowers per truss respectively in trial one. In trial two, field grown plants supplied with 300 kg NPK ha-1 had 11.32 flowers per truss. Greenhouse grown plants supplied with 300 kg NPK ha-1 had 20.61 and 14.19 aborted flowers in trial one and two respectively. High pollen viability was recorded from non-aborted flowers obtained from field grown plants supplied with 300 kg NPK ha-1 with a pollen viability of 94.48% and 93.97% in trial one and two respectively. Pollen from non-aborted flowers obtained from field grown plants supplied with 300 kg NPK ha-1 had the highest pollen germination of 68.72 and 67.72% in trial one and two respectively. Application of 200 and 300 kg NPK ha-1 for field and greenhouse grown pepino melon plants led to reduced flower abortion, high number of flowers per truss, high pollen viability and pollen germination.