A portable system to quantify seedling damage using stress-induced volatile emissions

Abstract

This paper describes a portable gas analysis system that was used to quantify stress-induced ethanol in black spruce (Piceamariana (Mill.) B.S.R). Operationally fall-lifted black spruce seedlings, packaged in polyethylene-lined kraft bags, were placed in a greenhouse to simulate conditions in the field, where stock may be exposed to elevated temperatures. The maximum temperature in the greenhouse was 36 °C, and the duration of heat treatment exposure ranged from 3 h to 7 days. After exposure to the heat stress event, the ethanol concentration in the bags of seedlings was measured using a portable gas analysis system. A sample of 20 seedlings were then potted and placed in a controlled-environment room for a 14-day growth period. At the conclusion of the growth period the seedlings were removed from the pots and the number of white roots >1 cm were counted. The terminal buds were dissected to determine viability, and the degree of foliage browning was estimated. The experiment was repeated four times. Ethanol concentration was significantly correlated with subsequent root growth potential, foliage viability, and terminal bud viability.