Spectral qualities and gas exchange affect the maturation and conversion of embryogenic cultures of Bactris gasipaes Kunth

Abstract

Somatic embryogenesis is the most used morphogenetic route for mass propagation of several species of the Arecaceae family, requiring adaptation to environmental conditions, such as the wavelength of light and gas-permeable membranes, which are essential characteristics for plant growth and development. Thus, the objective was to analyze the effect of spectral qualities and sealing types on the maturation and conversion of somatic embryos of Bactris gasipaes. Embryogenic calli (ECs) inoculated in flasks containing 50 mL of MS + Morel's vitamins + myo-inositol (100 mg L−1) + sucrose (30 g L−1) + casein (1 g L−1) + glutamine (1 g L−1) + asparagine (350 mg L−1) + 2.3 g L−1 Phytagel®, adjusted to pH 5.8, prior to autoclaving. The design was completely randomized, in a 4 × 2 factorial, four spectral qualities (white, blue, red, or red/blue LEDs), and two sealing types (rigid lids without holes or with two holes covered by membranes), ten repetitions, with 245 mg of the fresh mass of ECs per flask, kept in a growth room (27±2 °C, 16 h photoperiod, 50 µmol.m−2.s−1). At 120 days, the following were evaluated: color of ECs, conversion of somatic embryos; percentage of ECs with leaves, green and oxidized ECs (%), fresh and dry ECs (g), fresh weight gain, and water content of ECs (%). By means of the Biplot interpretation it was showed that EC should be subjected to blue and blue/red LEDs associated with flasks with gas-permeable membranes in order to enhance the conversion of somatic embryos to plantlets.