Controlled freezing stress treatment (Liliaceae)

Knowledge graph centered on Controlled freezing stress treatment (Liliaceae) with 30 nodes and 107 connections. Top connected: Delphinium, Asteraceae, Potentilla, Erigeron, Delphinium barbeyi.

Method synopsis

In situ freezing treatment using liquid nitrogen and heat exchanger to gradually cool plant tissues to -30°C. Designed to simulate natural freezing events while allowing controlled temperature ramping and monitoring.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure as described in the canonical source

Steps below were extracted from the paper that introduces this protocol — <i>In situ</i> photosynthetic freezing tolerance for plants exposed to a global warming manipulation in the Rocky Mountains, Colorado, USA (2004), New Phytologist. Implementations in other papers (listed below) may differ.

1. Conduct in situ Cold Experiment (ICE) treatment
   At least three terminal leaves per target plant were enclosed in a cylindrical styrofoam chamber (25 cm dia × 30 cm deep). Liquid nitrogen stored to pressurize overnight in a 70 L Dewar flask to 85 kPa. Air temperature adjacent to leaves and stems was lowered by adjusting a valve on the Dewar to vent cold nitrogen vapor through a coiled copper tubing heat exchanger (10 coils, 25 cm dia × 20 cm tall) inside the styrofoam chamber
   Quantities: At least 3 terminal leaves per plant, chamber 25 cm diameter × 30 cm deep, 70 L Dewar flask pressurized to 85 kPa, heat exchanger with 10 coils of 25 cm dia × 20 cm heightDuration: Temperature decreased from ambient (c. 10°C during experiments) to -30°C over 10 h, with extreme minimum temperatures in May reaching -30°CConditions: Freezing program was the same for all plants, conducted at a rate of 4°C h⁻¹, air and leaf temperatures continually monitored
   Equipment: cylindrical styrofoam chambers, 70 L Dewar flask, coiled copper tubing heat exchanger, digital microprocessor thermometer, Omega Model HH23, Omega Engineering Stamford CT

Typical Equipment

• cylindrical styrofoam chambers
• 70 L Dewar flask
• coiled copper tubing heat exchanger
• digital microprocessor thermometer

Output Measurements

• leaf temperature
• air temperature
• freezing stress response

Papers Using This Protocol (1)

Species Studied With This Protocol