Enhancing the drought-tolerance of rice with natural plant compounds

In this study, researchers at Hiroshima University examined the effectiveness of vanillic acid (VA) and p-hydroxybenzoic acid (PHBA) at increasing the drought-tolerance of rice cultivars, as well as their levels of beneficial compounds. Their findings were published in the Archives of Agronomy and Soil Science.

• For their experiment, the researchers used two rice cultivars, one drought-tolerant (Q8) and one drought-susceptible (Q2), and applied VA and PHBA on their leaves.
• Besides drought tolerance, they also looked at the two compounds’ ability to induce the production of pigments, antioxidants, phenolics, flavonoids and phytoalexin momilactones A (MA) and B (MB).
• The researchers observed that the compounds increased the tolerance level of Q2 more than they did Q8.
• They also increased the total phenolic, flavonoid and pigment content of the cultivars, as well as their antioxidant activity.
• The difference between Q8 and Q2 was negligible.
• In terms of phenolic acids, VA, PHBA and VA+PHBA had dose-dependent variable effects, with Q2 benefiting more from treatment than Q8.
• PHBA had a more significant effect in terms of drought tolerance than VA.
• Although MB was found only in non-treated Q8, VA+PHBA induced the production of both MA and MB.
• However, the amount of MA and MB produced varied depending on the applied doses of VA and PHBA and the rice cultivars.

Based on these findings, the researchers concluded that VA and PHBA can increase the antioxidant activity and total pigment, phenolic and flavonoid content of rice cultivars, as well as induce the production of MA and MB to enhance drought tolerance. MB may play a greater role than MA.

Journal Reference:

Quan NT, Xuan TD. FOLIAR APPLICATION OF VANILLIC AND P-HYDROXYBENZOIC ACIDS ENHANCED DROUGHT TOLERANCE AND FORMATION OF PHYTOALEXIN MOMILACTONES IN RICE. Archives of Agronomy and Soil Science. 18 April 2018;64(13). DOI: 10.1080/03650340.2018.1463520