|Principal Investigator||Stasolla, Claudio, University of Manitoba|
|Total Project Funding||$213,900|
1) Development of a reliable in vitro system to evaluate drought tolerance Drought stress in vitro will be simulated using the osmotic agent polyethylene glycol (PEG). Different levels of PEG will be applied to reach different levels of water potential ranging from mild to severe water stress. 2) Screening commercial soybean varieties for drought tolerance Selected soybean varieties will be screened for drought tolerance using PEG under conditions of mild or severe water stress (Objective 1). Screening will be performed both during germination, by measuring the percentage of seeds able to germinate under different levels of drought, and at the V1 stage of development. Growth characteristics, including fresh and dry weight of roots and shoots, and several gas exchange parameters, including photosynthetic rate, foliar CO2 level and water use efficiency will be measured. 3) Assessing the use of phytoglobin as a marker for tolerance to drought Lines exhibiting the highest and the lowest tolerance to drought (characterized from Objective 2) will be selected for measuring the expression level of Pgb in both shoots and roots. Measurements will be conducted before and during the imposed stress to evaluate if the expression of Pgb correlates to the response of the lines to the imposed stress. To further confirm the participation of Pgb in water stress responses, plants over-producing or under-producing Pgbs (already available in our lab) will also be assessed for their ability to tolerate drought conditions.
The objective of this research proposal is to develop a cost-effective and reliable method for screening soybean cultivars for drought tolerance. The methodology uses an in vitro system in which the level of water stress applied to the plants can be easily manipulated and adjusted using polyethylene glycol as an osmotic agent.
Commercial soybean lines will be assessed for the ability to tolerate drought stress during germination, and during seedling establishment. Morphological growth parameters, as well as physiological measurements including photosynthetic rate, internal CO2 level and water use efficiency will be utilized to evaluate the response of the soybean cultivars exposed to different levels of water stress. Furthermore, the function of the protein phytoglobin (Pgb) and the possibility to use its expression level as a marker for predicting plant behaviour to water stress will be assessed using available methodologies to measure gene expression, as well as employing plants in which the level of Pgb has been experimentally altered.