Will Roots Play a Decisive Role in Forage Sorghum Production under Salt Stress?

Abstract

Root developmental plasticity might provide breeders with the opportunity to generate crops with more resistant root system designs to abiotic pressures such as salt stress. The potential influence of diverse root designs in a panel of sorghum varieties’ production and performance under salt stress was investigated in this study. Dry weight yield had a significant positive correlation with three root parameters: main root length, main root angle, and lateral root length. These root features have varying positive correlations with other salt tolerance indices. Interestingly, all root properties have a negative correlation with the electrolyte leakage. Except for the lateral root length, the negative correlations were significant in all other root features. This pattern holds true for other salt performance indices studied, such as total soluble sugar content, chlorophyll content, growth, and leaf area. Furthermore, there is an inter-variety variation in the contribution level of lateral root and main root length towards the total root length and this was found to influence yield and performance. These findings give a hint on the root architectural features that play a positive role in sorghum salt tolerance and improved forage yield.