Row spacing and seed physiological quality of Crotalaria species

Abstract

ABSTRACT Crotalaria crops have important uses, such as in green manuring, nematode control, biological nitrogen fixation and sugarcane reform in Savanna areas. Due to its strategic importance, knowledge about crotalaria seed production technology is a relevant factor to ensure the availability of high physiological quality seeds. This study aimed to assess the effect of two row spacings (20 and 40 cm) on the germination and vigor of Crotalaria ochroleuca and Crotalaria spectabilis seeds produced in two crop seasons (2018 and 2019). The experimental design was randomized blocks, with four replications, in a 2 x 2 factorial scheme (spacing x crop season), for each species. The climatic conditions during seed production significantly infuenced the physiological quality of the crotalaria seeds. The 2018 harvest, with more abundant rainfall and milder temperatures during flowering, provided more vigorous seeds for both species. The 20 cm spacing was more efficient to produce C. ochroleuca seeds with high physiological performance. Notwithstanding, C. spectabilis seeds showed a higher physiological quality when produced under 40 cm spacing than when produced under denser cultivation.