Photosynthetic gas exchange and chlorophyll fluorescence of female hemp plants during sexual reversal treatments

Abstract

Sexual reversal methods are commonly used in plant breeding programs, allowing male flowers from female plants or vice versa. This work evaluated sexual reversal methods in female Cannabis plants and their effect on gas exchange activity. Plants treated with 1, methyl-cyclopropene (1-MCP), and aminoetoxyvinylglycine (AVG) showed differences in net photosynthesis (A) and stomatal conductance (gs) between the periods before and after sexual reversal treatments. Quantum yield (Qy), electron transport rate (ETR), and non-photochemical quenching (NPQ) did not show a relationship to the treatments, an increase in Qy and ETR, and a reduction in NPQ were observed after applying treatments. 1-MCP, AVG, and STS (silver thiosulfate) were effective in sexual reversal, while photoperiod changes did not induce the formation of male flowers. Induction of sexual reversion in Cannabis plants did not generate variations in energy dissipation mechanisms through photosystems.