The objective of this study was to verify the physiologic quality of papaya tree seeds, in function of different levels of nitrogen application and irrigation levels. Papaya tree plants of the Golden cultivar (Solo group) were used set in double and single rows, in a total area of 5.04m² per plant and 120.96m² per plot. Treatments were consisted of five irrigation levels, equivalent to 70, 90, 110, 130 and 150% of the reference evapotranspiration, estimated by the Penman- Monteith (FAO-56) equation and four doses of nitrogen (10, 20, 30 and 40g/plant), provided monthly until the end of the experiment, with ammonia sulfate as source of this nutrient. Seeds were extracted from hermaphrodite fruits and washed in a metal sieve to remove the sarcotesta. The assessed characteristics were germination and vigor, estimated by germination tests, germination first count, seedling classification and weight of seedling dry matter. A completely randomized design with treatments in a factorial scheme was used. Data were submitted to variance and regression analyses. From the obtained results, it was concluded that the 10g dose of nitrogen associated to an irrigation level that corresponded to 109% evapotranspiration resulted in greater germination values; and that the nitrogen doses, associated to suitable irrigation levels, contributed significantly to the increase in papaya tree seed vigor.
nutrient; germination; vigor
