Nutrient Demand of Oil Palm Hybrids in Tropical America

The results of the nursery phase of the study were validated in commercial plantings of the Astorga, La Cabaña and Unipalma plantations, where field plantings for the second phase of the study are also located. We have confirmed that root production of the OxG hybrid is more prolific and dense, which results in better efficiency in the use of nutrients. The recommendation after three years of studies is therefore to use: 20 to 30 g N; 10 g P; 15 g K, and 0.5 g B per plant for a nursery period of 10 months. This represents about 50 to 70% of the standard N recommendation and about half the recommendation for the remaining nutrients.

The field sites in Cabuyaro (Meta, Unipalma Plantation), Paretebueno (Cundinamarca, La Cabaña Plantation) and Tumaco (Astorga Plantation) are all acidic (pH between 4.3 to 4.8), with low CEC (less than 3.5 cmol/kg), with very low available P in Paratebueno and Tumaco (less than 3 ppm) and marginally low P in Cabuyaro (5 ppm), and with elevated exchangeable aluminum (30% in Cabuyaro and above 65% in the other two locations). Oil palm growing on these sites is therefore expected to respond favorably to the use of lime and fertilizers. All these areas have suffered from bud rot disease in the past and are currently planted with OxG hybrids alone.

The studies in all sites are factorials with five application rates of N, P and K and supplemental application of Mg and B. The complete data analysis is under way, but the initial results suggest that about 0.38 kg N and 0.5 kg K per plant and year are sufficient to promote maximum leaf dry matter production (0.9 kg dry matter in the reference leaf No. 9). But the maximum observed total dry matter for a Coarí x La Mé cross (La Cabaña origin) was about 36 kg dry matter (all canopy) when 1 kg of K was used together with 0.75 kg of N. This apparent contradiction highlights the fact that the results should not be taken as a general recipe for all OxG hybrids, but instead that each material has particular nutrient demands according to its productivity and size.

Fedepalma is currently extending the number of studies to other plantations in the bud rot disease regions. Some plantations with more than five-year-old stands are included to evaluate the effect of nutrition in mature productive crops.