Sodium silicate treatment promotes suberin poly phenolic and silicon deposition, and enhances hardness and brittleness at muskmelon wounds

Silicon can enhance plant resistance to biotic stress by directly inhibiting pathogens, forming physical barriers, and inducing the synthesis of defense compounds. However, no study is available on silicon on fruit wound healing. Here, we found that sodium silicate enhanced the activities of phenylalanine ammonia-lyase, 4-coumarate coenzyme A ligase, and cinnamate-4-hydroxylase, and elevated levels of cinnamic, rho-coumaric, caffeic, ferulic, sinapic acids, and total phenols at fruit wounds. Sodium silicate accelerated the deposition of suberin poly phenolic and silicon at wounds, increased the hardness and brittleness and reduced their resilience of the healing tissues, which slowed weight loss by wounded fruit, and disease index in fruit subjected to Trichothecium roseum. Taken together, sodium silicate may promote wound healing in muskmelons by activating phenylpropanoid pathway, accelerating suberin poly phenolic and silicon deposition at wounds, and increasing the hardness and brittleness of healing tissues.