A screening test for the determination of ethylene sensitivity

Area of Science:

• Agricultural Science
• Plant Physiology

Background:

• Ethylene is a plant hormone influencing growth and development.
• Ethephon releases ethylene in plant tissues, serving as a tool to study ethylene's effects.
• Understanding crop sensitivity to ethylene is crucial for agricultural practices.

Purpose of the Study:

• To assess the relative sensitivity of important Canadian crops to ethylene.
• To identify specific plant developmental stages most vulnerable to ethylene exposure.
• To compare ethephon application effects with direct ethylene gas exposure.

Main Methods:

• Seven crop species (barley, wheat, oats, canola, field pea) were treated with ethephon at one of seven developmental stages.
• Vegetative and reproductive growth parameters (height, biomass, yield, seed quality) were measured.
• Visual ethylene toxicity symptoms were documented and compared to gas exposure.

Main Results:

• Barley, wheat, and canola exhibited highest sensitivity (reduced yield/quality) during late vegetative and early reproductive stages.
• Field peas showed no yield reduction but an increase in pod number, potentially boosting yield.
• Early vegetative ethephon application affected growth but not yield in most species.

Conclusions:

• The late vegetative to early reproductive phases are critical for barley, wheat, and canola sensitivity to ethylene.
• Ethephon application is an effective screening tool for identifying sensitive crop cultivars and growth stages.
• Field pea responses to ethylene differ, with potential benefits in pod development.