Abstract
About this talk
Polyploid species are generally considered to have better adaptative abilities than diploids. Previous work has shown that phenotypic variations are induced in the aerial citrus plant part related to stress resistance and polyploidy. However, information regarding the impact of polyploidy on the functioning of the root system are still scarce. Our objectives were to study the physiological, biochemical and genetic determinants regarding salt stress tolerance in diploid and tetraploid rootstock in an intra- or inter-specific genetic context (diploids lined with relatively fixed genotypes that could be similar to autotetraploids and diploids lined with a hybrid between two genotypes belonging to the genera Citrus and Poncirus that could be similar to an allotetraploid) in control and salt stress conditions. Salt stress adversely affects physiological and biochemical processes associated with plant growth, development and yield. A set of responses at cellular, molecular, metabolic, physiological allows plants to overcome the negative effect of salinity. Under salinity condition, all the tested genotypes showed a different response to salinity. Diploid Poncirus was shown to be the most sensitive genotype. The most salt stress tolerant rootstocks, especially the tetraploids, presented (1) a maintaining for a longer time of their photosynthetic activities, (2) stronger antioxidant defence mechanisms, (3) a better capacity for storage, transport and absorption of minerals and nutrients. Moreover, statistical analysis of the data revealed the interaction of ploidy and stress is the main factor that explains the response of the plants.
Speaker
About the speaker
