2018 ASHS Annual Conference

Nutrient concentrations of date palm (Phoenix dactylifera L) cv ‘Barhee’, ‘Deglet Noor’, ‘Khadrawy’, ‘Khalasa’, and ‘Medjool’ were compared with the breeding line ‘Deglet Noor BC5’ and ornamental Phoenix spp P canariensis, P roebelinii, and P reclinata. All palms were mature trees growing in a genebank maintained by the United States Department of Agriculture in a low desert environment and all received similar cultural care. Leaves were sampled as previously described and analyzed for total N, P, K, S, B, CA, Mg, Zn, Mn, Fe, and Cu. Concentrations of all nutrients studied, except for Mn and Cu, differed significantly (P > 0.05) between accessions. In general, macronutrient concentrations tended to be higher in the ornamental species than in P dactylifera but this was not true for all P dactylifera cultivars due to variations in macronutrient concentrations between P dactylifera cv. Regarding micronutrients, the differences in concentrations between P dactylifera cv were less pronounced than for macronutrients. Nutrient concentrations in P canariensis tended to be similar to P dactylifera, but were more variable and lower in P roebelinii and P reclinata, particularly with regard to micronutrients. These results may be useful in assessing nutrient status of production date palms and of ornamental Phoenix spp.