冰核细菌对低温胁迫下枇杷幼果中果肉超微结构的影响

Effect of INA bacteria on pulp cell ultrastructure of young loquat fruit

摘要: 以“早钟6 号”枇杷幼果为试材, 采用人工降温的方法, 观察接种冰核细菌后, 果肉细胞超微结构在冻害胁迫下的变化过程。结果显示: 冰核细菌不同程度地加重了冻害胁迫对枇杷果肉细胞壁、叶绿体和线粒体的破坏程度; 冰核细菌对叶绿体的破坏最明显, 其次是细胞壁、线粒体; 冰核细菌使叶绿体在-1 ℃发生胞内结冰导致细胞冻害, 而未感染冰核细菌的叶绿体则发生胞间结冰, 冻害类型不同; 与-1 ℃低温相比, -3 ℃低温条件下冰核细菌的破坏作用更强。表明冰核细菌的存在加重了低温对细胞的伤害。

Abstract: The effects of INA bacteria inoculation on “Zaozhong No. 6” pulp cell ultrastructure under freeze stress in young loquat fruits were studied with simulated low temperature. Results showed that INA bacteria aggravated damage to young fruit pulp cell wall, chloroplast and mitochondrial of loquat. INA bacteria inoculation damaged chloroplasts the most, followed by cell walls, mitochondria. INA bacteria inoculation caused chloroplast cell damage via intracellular freezing at -1 ℃. Different degrees of intercellular freezing also occurred in fruits without INA bacteria inoculation. INA bacteria inoculation damage was stronger at -3 ℃ than at -1 ℃. It therefore indicated that INA bacteria inoculation increased frost damage under low temperature conditions.