Effect of top-dressed potassium fertilization on the yield and quality of cucumber

ABSTRACT

The current study aimed to evaluate the effect of top-dressed potassium (K) application on the production of hybrid cucumber “Sapphire.” The experimental design was a randomized complete block, with five blocks of 0.80 × 0.40 m² each and eight replicate plants per block. The five fertilization rates of K used were 0, 45, 90, 135, and 180 kg K₂O ha⁻¹. Data collection consisted of the estimation of fruit diameter, fruits length, fruit fresh and dry weights, the number of fruits per plant, and the weight of fruits per plant. The number of fruits per hectare and the fruit fresh weight per hectare were calculated. Fruit tissue was analyzed for determination of macronutrient concentrations, pH, titratable acidity, soluble solids, sugar contents, and protein content. The data were statistically analyzed using regression analysis and analysis of variance (ANOVA). There was a significant effect of the fertilization rate of K on fruit diameter, fruit fresh and dry weights, macronutrients concentrations in fruits, titratable acidity, soluble solids, and reducing sugars. A quadratic equation was adjusted for the number of fruits per plant and per hectare; fruit yield per plant and per hectare, with maximum top-dressing doses, was estimated to be between 60 and 95 kg K₂O ha⁻¹. A linear increase was obtained in the pH. An increase in the K fertilization rate caused a linear decrease in the fruit length.

KEYWORDS:

• Cucumis sativus
• fertilizer
• macronutrient
• postharvest productivity

Additional information

Funding

The authors would like to thank Co-ordination for the Improvement of Higher Education Personnel (CAPES), National Council for Scientific and Technological Development (CNPq), and São Paulo Research Foundation (FAPESP) (Grant 2016/13915-5) for granting scholarship to this study.