3.5 | The polysaccharide content in the medium
P, DT, and DTP stresses can significantly reduce the polysaccharides content in the culture medium (p <0.05), and all groups except DP, TP, and DN stresses tend to reduce the content of polysaccharides in the culture medium (Figure 5). Additionally, drought or high-temperature can significantly alleviate the effects of the down-regulation of root polysaccharides secreted by phosphorus deficiency (e.g., DP and TP stresses) (p <0.05) (Figure 5-b). However, the synergistic stresses of drought and high-temperatures can exacerbate the suppressive effects of drought (e.g., DT stress) (p <0.05) (Figure 5-d). These results suggest that under abiotic stress, the root system of plants reduces the secretion of polysaccharides, thereby reducing the consumption of carbon and energy, but the effects of DP, TP, and DN stresses are not obvious.