外源氯化血红素对NaCl胁迫下加工番茄幼苗生理特性的影响

Effects of Exogenous Hemin on the Physiological Characteristics of Processed Tomato Seedlings Under NaCl Stress

以耐盐型加工番茄品系KT-7为试材,采用盆栽法,研究叶面喷施氯化血红素(hemin)、锌原卟啉(ZnPPIX)对NaCl胁迫(100 mmol·L^(-1))下加工番茄幼苗的生长参数、光合能力、保护酶活性和渗透性调节物质的影响,以期为缓解NaCl胁迫对加工番茄造成的伤害提供参考依据。结果表明:与NaCl处理相比,外源hemin能缓解盐胁迫对加工番茄幼苗造成的伤害,其中单独施加hemin提高了加工番茄幼苗的生长指标、光合色素含量、光合参数、K^(+)含量、K^(+)/Na^(+)、渗透调节物质含量、保护酶活性,降低了Na^(+)含量、相对电导伤害率、丙二醛(MDA)含量;施用抑制剂ZnPPIX(ZnPPIX和ZnPPIX+hemin)抑制血红素加氧酶1(HO-1)活性后,hemin的这种缓解作用受到限制。综上所述,hemin能提高番茄光合作用能力,提高保护酶活性,减轻膜脂过氧化作用,增加渗透性调节物质含量,从而提高加工番茄的耐盐性,而这种缓解作用可能与HO-1活性呈正相关。

Taking salt tolerant processing tomato strain KT-7 as test material,the pot culture method was used to study the effects of foliar spraying of hemin and zinc protoporphyrin(ZnPPIX) on the growth parameters,photosynthetic capacity,protective enzyme activity,and permeability regulating substances of processing tomato seedlings under NaCl stress(100 mmol · L^(-1)),in order to provide reference for alleviating the damage caused by NaCl stress on processing tomatoes.The results showed that compared with NaCl treatment,exogenous hemin could alleviate the damage caused by salt stress on processing tomato seedlings.Among them,applying hemin alone increased the growth indicators,photosynthetic pigment content,photosynthetic parameters,K^(+)content,K^(+)/Na^(+),osmotic regulating substance content,protective enzyme activity of processing tomato seedlings,and reduced Na^(+) content,relative conductivity injury rate,and malondialdehyde(MDA) content.After the application of inhibitors ZnPPIX(ZnPPIX and ZnPPIX+hemin) to inhibit the activity of heme oxygenase 1(HO-1),the alleviating effect of hemin was limited.In summary,hemin could improve the photosynthetic capacity of tomatoes,enhance the activity of protective enzymes,reduce membrane lipid peroxidation,increase the content of osmotic regulating substances,and thus improve the salt tolerance of processed tomatoes.This alleviating effect might be positively correlated with the activity of HO-1.