Characteristics of Organic Acid Secretion Associated with the Interaction between Burkholderia multivorans WS-FJ9 and Poplar Root System

Figure 4

Induced effect of 20 mg·L^–1 IAA on poplar roots secreting organic acids. The contents of both GA and malonic acid in different nutrient solutions cultured poplar had no significant differences. The normal-P solution was the modified Hoagland nutrient solution containing 136 mg·L^–1 KH₂PO₄ and for the 0-P nutrient solution, KH₂PO₄ was replaced by 74.55 g of KCl and pH value was 6.8; for the low-P solution, every 68 g KH₂PO₄ was replaced by 37.3 g of KCl and pH value was 6.7; and for the high-P solution, the content of KH₂PO₄ was doubled compared to the normal-P solution and pH value was 6.4.