Effect of Potassium Concentration on Some Agrophysiological Parameters of Pineapple Plants (Ananas comosus L. cv. Smooth Cayenne and MD2) Grown in Côte d'Ivoire

Introduction: The Ivorian production of pineapple was on the decrease from 213620 t in 1999 to 30000 t in 2013. This decline in the production of pineapple would in part be linked to the quality of the fruit that is acid and especially the sensitivity of the fruit to browning enzymatic. The deterioration of the fruit quality would be due to the absence of good adequate cultural practice.

Objective: The aim of this study was to determine the effect of the level of concentration of potassium applied on the physiological state of the pineapple plant.

Place and Duration of the Study: The experimental tests were conducted on the site of Nangui Abrogoua University (Abidjan, Côte d'Ivoire) from July 2015 to the end of October 2016.

Methodology: Four applications of potassium were applied in the 2nd, 4th, 6th and 7th month after sowing, with 20 g of K2O/plant (T0), 28 g of K2O/plant (T1), 34 g of K2O/plant (T2), 40 g of K2O/plant (T3).The chlorophyll content, potassium and proline accumulation as the biomass of the sheet of pineapples to the floral induction have been determined as a function of the amount of potassium applied to the plant.

Results: The results showed that the biomass and leaf area of pineapple increase with the amount of potassium applied up to 34 g of K2O/plant. The excess of this nutrient entails a reduction of the chlorophyll synthesis and accumulation of proline in the leaves.

Conclusion: In addition to the report K/N (which must not exceed 2.5), the additional inputs of potassium in the culture of the pineapples must also consider the report K/Mg=1 for a good productivity.