Stress Response Phenomics

  • Abiotic and Biotic Stress Response

  • Drought Tolerance and Drought Stress

  • Chemcial Stress

  • Cold Stress

  • Light Stress

Abiotic Stress

Abiotic Stress

The term abiotic stress describes all kinds of environmental influences that may stress plants and thus reduce yield or growth, in comparison to optimum growth conditions. It is an important aim of many breeding programmes to create increasingly stress tolerant plants. For a better understanding of how plants are able to deal with abiotic stress, it is important to impose abiotic stress on the plants in a very precise and quantitatively graded way. LemnaTec scanalyzer3D systems with moving field conveyor systems can assist in this task by imposing the following stressors on individual plants or groups of plants:

Abiotic stress assessment using LemnaTec scanalyzer technologies:

  1. Salt stress (precise watering with a combination of water and defined salt solutions, using the LemnaTec watering and weighing module + quantifying e.g. chlorosis by visible light colour imaging)
  2. Drought stress (adding defined amounts of water, using the LemnaTec watering and weighing module + NIR water imaging of soil and shoots)
  3. Nutrient stress ( adding nutrients in defined concentrations as excess solution to keep the nutrient level on a defined level, using the LemnaTec watering and weighing module + quantifying e.g. nitrogen deficits by visible light green colour imaging)
  4. Harmful mineral stress, e.g. with Boron present in the soil (adding boron to the soil, using the LemnaTec watering and weighing module + washing boron excretions off the leaves in the LemnaTec spraying unit + quantifying e.g. leaf tip burning by visible light imaging)
  5. Waterlogging (adding excess water to and removing it from pots, using the LemnaTec watering and weighing module)
  6. Heat or UV light stress (randomising the plants in high intensity irradiation fields with LemnaTec scanalyzer moving field conveyor systems, in order to homogenise these difficult to handle energy fields) 

Abiotic stress due to salt stress is simulated in pots by defined watering. LemnaTec watering systems can be used to expose plants to waterlogging as a very specific type of abiotic stress

Drought Tolerance and Drought Stress

Drought Tolerance and Drought Stress

Drought tolerance is the short description of a quite complex agronomic trait. It describes the ability of crops to survive and produce a significant amount of yield even under exceptionally dry growing conditions. Since drought as a climate-related phenomenon can develop at quite different times within the growing season and climate conditions differ massively between regions, there is not one general drought model to which a plant can be tolerant. As a result, plants need different strategies and reaction patterns to deal with drought. It is also part of the breeding process to define how plants should perform in case of drought. As this is ultimately a probability game, it massively depends on the expected kind, duration, frequency and intensity of drought if plants should follow one or the other concept.

Some drought tolerance (or drought resistance) reaction patterns:

  1. Increased root growth in the early growing season, to allow enhanced water extraction from deeper soil layers in case of an early drought.
  2. General absolute reduction of water evaporation, to save water for later drought periods during flowering and ripening.
  3. High water usage efficiency, to allow minimisation of water amounts needed in irrigation.
  4. Physiological reduction of leaf water evaporation with smaller leaves, leaf hairs etc.
  5. Prevention of extreme growth, even under favourable growing conditions, to avoid a complete breakdown during a later drought period.
  6. The ability to shed most leaves during drought periods, but also to build up new leaf biomass later on when growth conditions improve again.

Measurement of drought tolerance using LemnaTec scanalyzer phenotyping technology

To assess and understand the genetic and physiological background of these complex plant development patterns, a detailed analysis of plant development under highly controlled, simulated drought conditions is extremely helpful. LemnaTec scanalyzer3D systems for greenhouses and growth chambers or growth rooms are designed to control the water supply and soil humidity for each individual plant and at the same time to monitor water evaporation and plant development. Scanalyzer VIS-systems, for example, provide information on biomass development, plant architecture and short-term leaf reactions such as leaf rolling or drooping. Scanalyzer NIR-imaging allows the monitoring of leaf water content, showing how plants deal physiologically with a specific water regime. Scanalyzer IR-heat imaging modules deliver information on leaf temperature and stomata closure. LemnaTec scanalyzer root imaging quantifies root development in real soil, using transparent pots (VIS) and providing soil water extraction profiles based on NIR-imaging. These image-based data can be complemented by individual, high-frequency read-out systems for soil humidity, soil temperature or e.g. leaf thickness.

Drought tolerance is of primary interest for an increasing number of crops, in order to maintain adequate yield under stress conditions. LemnaTec scanalyzer watering systems provide individual plant watering solutions to simulate specific soil humidity profiles and to monitor water usage.