With the objective to evaluate the growth and nutrient accumulation by onion cultivars, experiments were conducted at the experimental station of Bebedouro (Petrolina, PE) of Embrapa Semiarid, during May to October 2009, and in Baraúna, RN, in commercial area, from June to October 2009. The statistical design utilized in the experiment was a randomized complete block design, RBD with four replications in a 2 x 6 factorial. Treatments were the combinations of two cultivars of onion (IPA 11 and Texas Grano 502) and six sampling times (15, 30, 45, 60, 75 and 90 days after transplanting - DAT). In each collection six plants per replication were used. The onion cultivars IPA11 and Texas Grano presented initially slow growth, increasing from 30 DAT. Greater increases in total dry mass, shoot and bulb occurred at 60-75 DAT. The nutrients were absorbed by the onion in the following order: Ca > K > N > Mg > P and Ca > N > K > Mg > P for 'Texas Grano 502" and "IPA11" in Petrolina and K > Ca > N > Mg > P and N > K > Ca > Mg > P for 'Texas Grano 502" and "IPA 11" in Baraúna. Cultivars Texas Grano 502 and 11 IPA exported more nutrients in Baraúna.
Allium cepa L.; dry matter accumulation; absorption curves; plant nutrition
