Lettuce seed germination from plant cultivated with different phosphorus levels

Abstract

This study was carried out at São Manuel Experimental Farm, UNESP/FCA, in Botucatu, São Paulo state, Brazil, with the objective to evaluate the lettuce seeds (cultivar Verônica) germination from plants cultivated with different phosphorus levels at harvest, in three temperatures and after two conservation period in dry chamber. At seed production stage, the experiment was conducted in randomized complete blocks, with five treatments (0; 200; 400; 600 and 800 kg ha^-1 of P₂O₅) and five replications. After harvesting, seed germination at 20^oC and under high temperatures (30 and 33ºC) was evaluated. After 15 and 25 months of conservation in dry chamber room it was evaluated germination at 20ºC. The P₂O₅ levels evaluated did not affect seed germination soon after harvesting at the three temperatures evaluated, but, the higher the temperature, the lower the seed vigor. After 25 months of conservation, the lesser the P₂O₅ rates, the lesser seed germination and germination speed index.