Khalas and Khasab date cultivars were fertilized by urea, triple superphosphate, potassium sulphate with or without micronutrients and date palm fiber mulch. Half the palms were pollinated by hand and the other half by handpollen duster (mechanical) in a CRD design with 3 replications for 3 successive years. Fruit length, diameter, weight, number and weight/strand and total yield were determined. Pollination effect was not significant on Khalas and Khasab fruits number and weight/strand and fruit diameter. Khalas yield was higher after mechanical pollination, but with lower fruit length and weight than hand pollination. This effect was not significant on Khasab. Fertilizer effect was not significant on producing longer Khalas fruits than NPK supported by mulch. Khasab higher yield and longer fruits of larger diameter were produced by NPK with micronutrients and mulch than mulch alone on yield and than all other fertilizer treatments on fruit length and diameter. Interaction effect for pollination method and fertilizer mulch was not significant on all the tested physical parameters. But certain variations indicated an important trend that can furnish guide lines for improving date physical qualities, soil conditioning and reduced cost of production. The general trend with most of fertilizer/mulch treatments indicates that Khalas yield was higher by mechanical whereas, Khasab by hand pollination than mechanical. Mulch increased Khalas yield by mechanical pollination when NPK and micronutrients were applied by 25% over NPK alone. The same treatment combination produced the highest Khasab yield by mechanical pollination. It consistently produced the longest Khasab fruit with largest diameter and heavier single fruit by mechanical pollination than other treatments. Application of NPK with micronutrients and mulch produced comparable Khalas fruit length and diameter and larger than the average Khalas fruit size in Oman. It can be concluded that application of NPK and micronutrients supplemented by date palm fiber combined with mechanical pollination produced the most desirable physical characteristics than most of the treatments. And discrepancies from this could easily be ameliorated or overridden by economical and environmental benefits.
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