真空浸渍辅助BTH-Ca^(2+)复合处理对甘薯采后愈伤能力的影响

Effect of Vacuum Impregnation Assisted BTH-Ca^(2+)Treatment on Wound Healing Ability of Sweet Potato

以“心香”甘薯为研究对象,采用人工机械损伤方式,探究真空浸渍辅助BTH-Ca^(2+)复合处理对甘薯采后伤口愈合能力的影响。以木质素含量为指标,通过单因素和响应面优化实验,得出促进甘薯愈伤的最佳处理参数为:BTH质量浓度为100 mg/L、乳酸钙质量浓度为14.1 g/L、真空度为15 kPa、真空浸渍时间为6.5 min,在此条件下愈伤2 d,甘薯损伤部位木质素质量分数达195.06 mg/g,显著高于对照组(P<0.05)。BTH-Ca^(2+)复合处理明显提高甘薯愈伤组织的苯丙氨酸解氨酶(PAL)、肉桂酸羟化酶(C4H)、4-香豆酰-辅酶A-连接酶(4CL)、肉桂醇脱氢酶(CAD)和过氧化物酶(POD)活性,其中,PAL、4CL、CAD和POD活性与木质素含量呈极显著正相关(P<0.01)。由此可见,在适宜的条件下,BTH-Ca^(2+)复合处理可通过激发甘薯损伤部位的苯丙烷代谢途径,正向调控木质素的合成和积累,达到促进愈伤的目的。

The effect of vacuum impregnation technology assisted BTH-Ca^(2+)treatment on postharvest wound healing ability of sweet potato cultivar‘Xinxiang’was studied by artificial mechanical injury.Based on single factor and response surface optimization experiments with lignin content as the index,the optimum treatment conditions were obtained as follows:BTH concentration 100 mg/L,calcium lactate concentration 14.1 g/L,vacuum degree 15 kPa,and vacuum immersion for 6.5 min.Under these conditions,wound healing was conducted for 2 days,the lignin content in the injured part of sweet potato was 195.06 mg/g,significantly higher than that in the control group(P<0.05).After treatment,the activities of phenylalanine ammonia lyase(PAL),cinnamate hydroxylase(C4H),4-coumaryl-coenzyme A-ligase(4CL),cinnamyl alcohol dehydrogenase(CAD)and peroxidase(POD)in calluses were significantly increased by BTH-Ca^(2+)treatment,and the activities of PAL,4CL,CAD and POD were positively correlated with lignin content(P<0.01)significantly.In conclusion,under appropriate conditions,BTH-Ca^(2+)treatment could positively regulate the synthesis and accumulation of lignin by stimulating the phenylpropane metabolic pathway in the injured part of sweet potato,and achieve the purpose of promoting wound healing speed.