A systemic approach to understand plants' responses under abiotic stress: a laboratory exercise for undergraduate biology majors

摘要

This article describes a ten week long laboratory exercise designed for undergraduate students aimed at enhancing their understanding of physiological and biochemical responses of plants under dehydration stress. Hypothesis was built around previous reports which suggested that exogenous application of certain elicitors leads to transient alleviation of dehydration stress in plants. The chosen elicitors were Calcium and Sodium Nitroprusside (Nitric Oxide elicitor) which were tested on Rice plants under dehydration stress. The experiments were divided into four categories: 1. Water Status and Osmotic adjustment: relative water content (RWC) and Proline content 2. Oxidative Damage: Lipid peroxidation of membranes, electrolyte leakage, total peroxide level 3. Metabolic Health: photosynthesis pigments (chl a, b and carotenoids) and 4. Reactive oxygen species (ROS) scavenger enzymes: ascorbate peroxidase (Apx) and catalase (CaT) assays. The instructor along with the teaching assistants acted as a mentor by initially training the students in the required technical skills and then later guiding them through the course of the project. This curriculum embedded research exercise was designed to foster science process skills and develop integrative thinking for solving scientific problems by employing a hands-on approach in a plant physiology laboratory course.