ABSTRACT
Specific knowledge on dormancy and germination patterns of weed species aids the development of integrated management strategies. This study aimed to evaluate and select effective methods for overcoming dormancy in B. latifolia seeds, as well as determining their influence on the germination process. A completely randomized experimental design was used, with four replications and 20 seeds per repetition. Seven tests were conducted, with the corresponding B. latifolia seed treatments: Test 1 - mechanical scarification, sulfuric acid, hot water and running water; Test 2 - pre-cooling at 4 °C and dry heat at 60 °C. Test 3 - gibberellic acid at concentrations of 0, 50, 100, 200 and 400 ppm; Test 4 - acetic acid and potassium nitrate 2%; Test 5 - dual combinations of the three best treatments observed in the first four tests. Test 6 - pre-soaking in a sandbox and in germination paper and; Test 7 - imbibition curve. The seeds were submitted to the germination test in BOD at 25 °C with a photoperiod of 12h, in transparent polypropylene boxes. Germination percentage (GP), mean germination time and relative frequency of germination were determined and the weight of the seeds after soaking in Test 7 was measured. The best treatments for overcoming seed dormancy were dry heat, gibberellic acid 283 ppm and KNO3 3h. The association of dry heat + potassium nitrate 3 h and potassium nitrate 3 h +gibberellic acid increased germination percentage by 25% compared to isolated treatments.
Key words:
Broadleaf buttonweed; Overcoming; Dormancy; Soaking; Rubiaceae
