Effect of phosphorus levels on yield and postharvest storage of onion cultivars

ABSTRACT

Phosphorus is recognized as a key nutrient to obtain high productivity and macronutrient that has been most often limits the production in soil poor in nutrient. With the objective of evaluating the influence of phosphorus levels and cultivars on yield and storage postharvest was carried one trial in Petrolina-PE, Brazil, from May to December 2011. The experimental design was a completely randomized block in a 5 x 2 factorial scheme, composed of five phosphorus levels (0; 60; 120, 180 and 240 kg ha^-1) and two cultivar (Franciscana IPA-10 e Vale Ouro IPA-11) with four replications. The Franciscana IPA-10 cultivars (74.6 t ha^-1) and Vale Ouro IPA-11 (76.1 t ha^-1) showed no significant differences in commercial yield of bulbs. Highest commercial yield were obtained at dose of 132 kg ha^-1 P₂O₅ was associated with economical dose of 130 kg ha^-1 P₂O₅. It was verified with increasing levels, a gradual reduction in the production of bulbs considered non-commercial (culls), and the lower production estimated of culls was estimated dose of 121 kg ha^-1 P₂O₅. Commercial bulbs of higher fresh mass and diameter were obtained with the increment of phosphorus. There was no loss of significant mass after 30 days cure at doses or cultivars. At 60 after curing, it was detected a significant effect only for cultivars with less loss to cultivar Franciscana IPA-10 (27.2%) compared the cultivar Vale Ouro IPA-11 (31.9%).

Key words:
Allium cepa L.; yield, nutrition; conservation