Application of jasmonic acid boosts accelerative effects of silicon addition on rice defense against invasion of apple snails (Ampullariidae)

Abstract Background The invasion of apple snails ( Pomacea spp.) has a serious negative impact on the yield of aquatic crops, including rice, which is a vital food source for more than half of the global population and irreplaceable in maintaining the global food security of human society. So far, it has been unclear whether jasmonic acid (JA) application can enhance the effects of silicon addition on the defense of crops like rice against the invasion of apple snails. Rice plants were grown in a greenhouse and subjected to treatments involving the addition of silicon (sodium silicate) and JA (methyl jasmonate). Then, in an indoor experiment, apple snails were fed with the leaves of the rice plants that had undergone the treatments. Growth and growth-related traits for rice plants and apple snails and defense-related mechanic characters for rice plants were measured. Results Silicon addition significantly increased rice growth, leading to improved biomass and relative chlorophyll content. JA application did not affect the growth of rice plants but increased their foliar nitrogen and carbon content disproportionally, leading to a reduced C/N ratio. JA application increased the levels of tannins, total phenolics, and flavonoids in rice leaves. Silicon addition increased the tannin, total phenolic, and flavonoid content in rice leaves, particularly when supplied with JA. Silicon addition could also enhance the force of fracture in rice leaves. In addition, the foliar sulfur and silicon content increased with the addition of silicon, and the combination of silicon addition and JA application resulted in the highest foliar silicon content. Both silicon addition and JA application significantly decreased weight gain, leaf consumption, relative growth rate, and cellulase activity of apple snails, indicating a strong interaction. Conclusions Overall, these findings indicated that both silicon addition and JA application enhanced the defense of rice against apple snails and impeded the growth of these snails. JA application amplified the impact of silicon addition on rice’s defense mechanism. This study provides new insights into controlling biological invasions and their impact on crop yield.