Plant stress responses and adaptation

Course title:

Plant stress responses and adaptation

Course code:

AFPSA

ECTS:

3

In-class hours

Lectures:

15

Laboratory work/Tutorials:

15

Self-preparation hours

Practical training:

-

Other:

45

Total hours:

75

Language:

English

Study cycle:

Bachelor, Master, PhD

Semester:

Winter & Summer

Faculty:

Faculty of Agronomy

Name of the lecturer(s):

Prof. Andon Vasilev, PhD

Mode of delivery:

Face-to-face, distance learning, combination of  both

Prerequisites:

-

Learning outcomes of the course unit:

The course gives theoretical knowledge about stress responses, acclimation and adaptation of plants to different stress factors as well as stress-induced plant functional disorders and damages.

The course starts with information about general stress concepts and molecular bases of both stress perception and creation of signals. It continues with the characterization of the so-called “oxidative stress” as a mediator of plant responses to different stress factors. Further, physiological mechanisms of plant adaptation as well as functional disorders at selected stress situations are described.

A part of the course addresses plant performance at cardinal environmental stresses, such as (1) lack and surplus of light, (2) heat, frost and cold, (3) drought, (4) flooded soils and (5) mineral deficiency, which are foreseen for discussions during the seminars.

The topics presented by lectures include (6) soil heavy metal pollution, (7) soil salinity and acidity, (8) air pollutants, (9) herbicides as well as some (10) biotic stresses (herbivory, infection, allelopathy). In addition, different methods to measure plant stress are described together with some recommendations to reduce or ameliorate stress-induced plant damages

Course contents:

LECTURES:

1. Plant organism as integral, self-regulating and adaptive system. Strategies for plant protection from stress factors. Stress induction, stress perception and creation of signals. Stress responses, acclimation and adaptation of plants to environmental conditions. Single and combined effects of stress factors on plants: additive, synergetic and antagonism. Oxidative stress in plant cell as nonspecific mediator of different stress responses. Free radicals and reactive oxygen species. Antioxidative plant defense network. Suitable indicators of plant performance at stress situations.

2. Plant adaptation, physiological responses and damages induced by heavy metals. General characteristics of problematic heavy metals. Heavy metal tolerance. Metallophytes and hyperaccumulator plants. Heavy metal ion pumps. Polypeptides induced by heavy metals – metallothioneins and phytochelatins. Heavy metal phytotoxicity. Phytoremediation.

3. Plant responses, adaptation and damages induced by xenobiotics. Herbicides. Modes of action and detoxification of commercial herbicides. Mechanisms of herbicide selectivity. Gaseous air pollutants. Uptake, transformation, translocation and physiological effects of ozone, SO2, NOx in plants. Sensitive and tolerant plants to air pollutants. Biomonitoring.

4. Physiological changes, damages and plant adaptation to saline and acidic soils. Physiological effects of salt stress – primary and secondary effects. Restoration of ion homeostasis, osmotic adjustment, protective proteins. Negative effects of acidic soils. Aluminum phytotoxicity, mechanisms of plant resistance and tolerance.

5. Physiological changes, damages and plant adaptation to some biotic factors. Herbivory: signal transduction chain and physiological effects. Pathogen infection and defence. Fungal infection, induced defense, systemic acquired resistance. Allelopathy. Parasitic associations.

SEMINARS:

1. Physiological changes, damages and adaptation mechanisms of plants to lack and surplus of light. Structural-functional differences in the photosynthetic apparatus of light-adapted and dark-adapted leaves. Etiolating. Photoinhibition. Physiological disorders in plants induced by UV-B radiation.

2. Physiological changes, damages and adaptation mechanisms of plants to low and high temperatures. Physiological changes and damages in plants induced by low positive and negative temperatures. Mechanisms of plant resistance to both chilling and frost. Physiological changes and damages in plants induced by high temperatures.

3. Physiological changes, damages and plant adaptation to drought. Water balance in drought–stressed cells. Cellular reactions to drought stress. Perception of dehydration stress. ABA-mediated stress response.  Signal transduction. Function of induced proteins and accumulation of osmolytes. CAM metabolism. General anatomical and morphological adaptation to drought.

4. Physiological changes, damages and plant adaptation to flooded soils. Anaerobiosis and hypoxia. Energy metabolism of plants under oxygen deficiency. Changes in metabolism caused by hypoxia. Anatomical-morphological changes – elongation, aerenchyma. Post-anoxic stress.

5. Physiological changes, damages and plant responses to mineral deficiency. Acquisition of macro- and micronutrients in soil. Root traits that determine nitrogen and phosphate acquisition. Strategies of plants for iron uptake. Plant deficiency symptoms of selected micronutrients. Possibilities to reduce or ameliorate nutrient deficiency by leaf-applied fertilizers.

Recommended or required reading:

1.       Schulze, E.-D., Beck, E., K. Muller-Hohenstein. Plant Ecology, 2002. Springer.

2.       Lambers, H., Stuart Chapin III, F., Pons, T. L., 1998. Plant Physiological Ecology, Springer.

3.       Datnoff, L. E., Elmer, W. H., Huber, D. M., 2007.  Mineral nutrition and plant disease. The American Phytopathological Society.

4.       Lambers, H., Stuart Chapin III, F., Pons, T. L., 2008. Plant Physiological Ecology, 2nd ed., Springer.

5.       Orcutt, D.M., E.T. Nilsen, 1996. Physiology of plants under stress. Soil and biotic factors. Wiley.

Planned learning activities and teaching methods:

The course includes the following mandatory components: lectures, seminars as well as student self-preparation.

The lectures are supported by extensive literature and material basis. The lectures are delivered by means of PowerPoint presentations.

The seminars take the form of a discussion between the students and the lecturer, with reference to the above-mentioned topics.

Assessment methods and criteria:

The course ends with a written examination. The latter includes a pre-defined set of questions, which is drawn from the course material.

The grading will conform to the 6-grade system. The results will be published no later than 2 weeks after the exam.