MELO, Gérsia Gonçalves de.; SILVA, Maria Dulcinea Freitas da.; COSTA, Djayran Sobral.; CARVALHO, Islan Diego Espindula de.; SALES NETO, José Marreiro de.; BRAZ, Luana Camilla Cordeiro.; ARAÚJO, Bianca Galúcio Pereira.; CARVALHO FILHO, José Luiz Sandes de.
Résumé:
Our purpose was evaluate effect of different levels of nitrogen fertilization
on different lettuce varieties, aiming to determine best level for each variety.
Experimental design included a randomized complete block design, in 5x4 factorial
arrangement, combining five nitrogen levels (0, 30, 60, 120, 240 kg.ha-1) and four lettuce
varieties (Amanda, Elba, Solaris e SVR 2005) with three replications. Nitrogen source
was urea, which was applied in two times: half at seven days after seedlings
transplanting and half at 28 days after transplanting. Evaluated variables included total
productivity, average plant weight, average leaf weight, number of leaves per plant and
head diameter. The nitrogen levels that generated a highest productivity were 6, 6, 12,
and 24 g.m-1 for Elba, Amanda, Solaris, and SVR 2015, respectively. These results allow
a productivity increase, with increase of financial return to producer, since it indicates the
best management condition for each lettuce variety.