ABSTRACT

With the objective os studying the behavior of germination of the best ten genotypes developed by Embrapa Breeding Program of upland cotton (Gossypium hirsutum L. race latifolium H.) of media fibers, and to identify the more and the less sensitive, in six levels of the osmotic potential (0.0, -0.2, -0.4, -0.6, -0.8 and -1.0MPa), induced by polyethylene glycol-6000, a trial in laboratory was carried out, making use of the Germitest paper, in a experimental design completely randomized, in a 10 x 6 factorial scheme, with 4 replications, each consisting of 50 seeds. There was difference of behavior between the genotypes in study of cotton, between different water stress levels. The percentage of deteriorated seeds and abnormal seedlings, on ten genotypes declined, but the percentage of seeds without absorption of water increased, in the major PEG-6000 concentration levels. The cultivars CNPA Precoce 2 and CNPA Precoce 1 are the less sensitive to reduced osmotic potentials (-0.6 and -0.8MPa), while LG ROGERS and CNPA 7H are more or less sensitive. The lineage CNPA 86-1195-1 is the most sensitive.

Key words:
water potential; drought simulation; PEG-6000; germination