Effect of Planting Density and K2O:N Ratio on the Yield, External Quality, and Traders' Perceived Shelf Life of Pineapple Fruits in Benin

Abstract

Quality, shelf life, and yield of a pineapple fruit are the important attributes for the producers and customers in the pineapple value chain of Benin, whereas poor quality, short shelf life, and low yield are the main constraints. We quantified the effects of planting density and K2O:N fertilizer ratio on the pineapple yield, external quality, and perceived shelf life in four on-farm experiments with cv. Sugarloaf in Benin; two experiments were installed in the long rainy season and two in the short rainy season. A split-plot design was used with the planting density as the main factor at three levels: 54,000, 66,600, and 74,000 plants.ha−1. The K2O:N ratio was a subfactor with three levels: K2O:N = 0.35 (farmers' practice), K2O:N = 1, and K2O:N = 2. The results showed that both factors had no effect on the crop development variables (such as the number of functional leaves and D-leaf length) at the moment of flowering induction. The planting density had no effect on the total weight per fruit, infructescence weight, total fruit length, infructescence length, crown length, or the fruit shelf life as perceived by traders. The yield increased from 54.9–69.1 up to 90.1 t.ha−1 with an increase in the planting density. The yield increase was not at the expense of the fruit weight. Increased K2O:N ratio led to a higher fruit weight whereas the fruit length was not affected. The shelf life of fruits produced at a K2O:N ratio of 1 and as perceived by traders was 6 days longer than that of fruits produced at a ratio of 0.35 (farmers' practice). Based on these results, we suggest the fresh pineapple farmers in Benin to use a combination of 66,600 plants.ha−1 with a K-fertilization scheme based on a K2O:N ratio of 1 to meet the expectation of both producers and customers in terms of fruit yield and fruit quality.

Typologies of pineapple-based farming systems in Centre-Cameroon

“…32.1% of producers in the Awae locality belong to the second production system. For this system, the K/N ratio of 1.04±0.4 indicates an inferior quality of marketed fruit explaining consumers complaints in this locality (Djido et al, 2021). Also, labor force used in pineapple farm is not qualified and same farmer have not received training in management of pineapple field.…”

“…Pineapple production in type 2 and 3 (mostly found in Awae locality) is conventional (Darnaudery et al, 2018), dominated by blanket fertilization recommendation. For these practices, the K/N ratio is below or above the recommended dose and leads to a reduction in crop yield and fruit quality (Sossa et al, 2017;Djido et al, 2021). The low planting density contributes to low yields (de Souza et al, 2019;Sanya et al, 2020).…”

“…The low planting density contributes to low yields (de Souza et al, 2019;Sanya et al, 2020). Djido et al (2021) showed that, high planting density does not influence the weight of the fruits. This observation is contrary to the assertion of producers; planting densities are reduced to obtain larger fruits.…”

“…For this shifting cultivation system, the abandonment of cultivated fields is not only due to soil fertility decline, but pathogens also harbored in the soil (Rohrbach and Johnson, 2003). The technical level of producers in type 2 is low and typical of African pineapple producers (Djido et al, 2021). 32.1% of producers in the Awae locality belong to the second production system.…”