In vitro culture of sugarcane exposed to different light sources

O objetivo deste trabalho foi avaliar o efeito de diferentes comprimentos de onda no desenvolvimento in vitro de mudas de cana‑de‑açúcar. Explantes foram submetidos a quatro tratamentos de diodos emissores de luz (LED): 100% azul; 70% azul + 30% vermelha; 30% azul + 70% vermelha; 100% vermelha, além do controle com lâmpada fluorescente branca. As plântulas foram avaliadas quanto a: número de brotações; altura; massa de matéria fresca e seca; e conteúdo de carotenoides e das clorofilas a e b. Observou-se desmanche dos tilacoides nos cloroplastos, proporcional ao aumento na incidência de luz vermelha. O porte das mudas diminui com o aumento na incidência de luz vermelha.The objective of this work was to evaluate the effect of different wave length on the in vitro development of sugarcane seedlings. Explants were subjected to four light emitting diodes (LED): 100% blue; 70% blue + 30% red; 30% blue + 70% red; 100% red, besides the control with white fluorescent lamp. Seedlings were evaluated for: number of shoots; height; fresh and dry matter mass; and contents of carotenoids and chlorophyll a and b. It was observed thylakoid disarrangement in the chloroplast, proportional to the increasing incidence of red light. The size of the in vitro produced seedlings reduces with the increase of red light incidence