Features of germination, emergence modeling, longevity, and persistence in Bidens pilosa seed bank

Abstract

Abstract To develop models capable of predicting the emergence of hairy beggarticks and assist integrated management, it is fundamental to have knowledge of the environmental factors that influence the germination of the species. The objective of this study was to estimate temperature and water potential cardinals for hairy beggarticks germination, the longevity of its seed bank, and to develop a model of its emergence in the field. Experiments were carried out in the laboratory to determine the temperature and water potential base for seed germination. Eight different temperatures (10.0, 15.0, 20.0, 25.0, 30.0, 35.0, 40.0, and 45.0°C), and 10 different water potentials (0, -0.05, -0.1, -0.2, -0.4, -0.6, -0.9, -1.2, -1.5, and − 2.0 MPa) were tested. The field experiments were conducted between 2014 and 2019 using three monitoring seedling emergences. To evaluate the longevity and persistence of the seed bank, a factorial experiment was conducted with three burial depths (0, 3, and 6 cm) and five seed retrieval moments (0, 1, 4, 10, and 16 months). Base, optimal, and maximum temperatures for hairy beggarticks germination are 10.4°C, 24.7°C, and 41.8°C, respectively. The base water potential for the emergence of hairy beggarticks is -0.85 MPa. The thermal and hydrothermal time models are adequate to predict the emergence of hairy beggarticks in different soybean sowing dates. The species has a transient seed bank, however, the greater the seed burial depth, the greater the longevity of the soil seed bank.