# Anthocyanin accumulation, inflorescence dry weight and total cannabidiol content have different temperature optima in Cannabis sativa

## TL;DR

This study shows that temperature affects anthocyanin, CBD, and inflorescence dry weight in cannabis differently, with anthocyanin peaking at 8°C and 15°C.

## Contribution

The study identifies distinct temperature optima for anthocyanin accumulation compared to CBD and inflorescence dry weight in Cannabis sativa.

## Key findings

- CBD and inflorescence dry weight increase with temperature, likely due to plant maturity.
- Anthocyanin peaks at 8°C and 15°C, indicating temperature-dependent regulation.
- Anthocyanin levels drop at 0.5°C and 22°C, suggesting optimal ranges for biosynthesis.

## Abstract

Limited information exists on how temperature affects phytocannabinoids and anthocyanin accumulation and inflorescence dry weight yield in Cannabis sativa. Understanding how temperature influences these traits is essential for refining cultivation practices, meeting market demands, and developing novel cannabis cultivars with improved agronomic, medicinal, and aesthetic attributes.

In this study, a day-neutral inbred population with uniform expression of purple pigmentation on the leaves and flowers was used to explore how temperatures ranging from 0.5 to 22 °C impacts inflorescence dry weight, cannabidiol (CBD) percentage, and anthocyanin accumulation in cannabis. Data on inflorescence dry weight (g/plant), CBD (%), and anthocyanin concentration (mg∙L− 1) in the primary inflorescence of each plant were collected and analyzed.

Total CBD concentration and inflorescence dry weight yield increased with increasing temperature– likely a result of plant maturity rather than temperature stimuli. Anthocyanin accumulation was significantly affected by temperature stimuli, exhibiting peak production levels at constant temperatures of 8 °C and 15 °C.

CBD concentration and inflorescence dry weight predominantly correlate with plant maturity, whereas anthocyanin accumulation is responsive to variations in environmental temperature. Maximum anthocyanin levels at 8 °C and 15 °C, along with reduction at 0.5 °C and 22 °C, suggests distinct temperature-dependent regulatory pathways for anthocyanin biosynthesis in cannabis, separate from those influencing CBD biosynthesis and inflorescence dry weight. Modeling anthocyanin concentration, CBD concentration, and total inflorescence dry weight across various temperature treatments could optimize desired floral qualities and other traits associated with yield in cannabis.

The online version contains supplementary material available at 10.1186/s42238-025-00311-w.