Temperature effects on seed germination in races of common beans (Phaseolus vulgaris L.) - DOI: 10.4025/actasciagron.v28i2.976

Abstract

Temperature is one of the most important environmental factors, affecting establishment and crop development. Seed germination is particularly affected by temperature. The aim of this work was to evaluate the tolerance temperatures during germination in several bean cultivars. The seeds were submitted to temperatures ranging from 8 to 45°C in thermal block apparatus and primary root protrusion time. The number of germinated seedlings was scored for each cultivar and temperature. High temperatures (≅40°C and upper) strongly inhibit cultivar germination, but 'IAPAR-57', ‘Guarumbé’ and ‘Iratim’ appear to be more sensitive to high temperature stress than others. ‘IAC Carioca 80SH’ PP and 'IAPAR-57' were less tolerant to low temperatures. The thermal time model could describe, relatively well, the time-course of the cultivars isothermal germination, which differed in the thermal time amount required to germinate. 'IAC Carioca-Akytã' needs fewer degrees per day to achieve germination than others, whereas the cultivar 'Campeão-1' requires more thermal time.