AM真菌孢子保藏条件的研究——以异形根孢囊霉为例

Preservation Conditions of AM Fungal Spores:A Case Study of Rhizophagus irregularis

为探究丛枝菌根(arbuscular mycorrhiza,AM)真菌纯孢子短期、中期保藏的最佳条件,将异形根孢囊霉(Rhizophagus irregularis,Ri)纯孢子保藏于30%甘油、30%甘油+植物组培抗菌剂(plant preservation mixture,PPM)、纯水、纯水+PPM 4种不同介质当中,于4℃和-20℃条件下保藏2个月和5个月后,将孢子液接种宿主植物根系,测定不同保藏条件对Ri孢子侵染宿主能力的影响。结果表明,1)保藏5个月、4℃纯水介质中大量休眠孢子打破休眠,显著提高Ri孢子液活性,与初始相比提高5.08%~11.07%,其他条件下Ri孢子活性随着保藏时间的增加而降低。2)保藏2个月后,其活性在甘油和纯水2种介质以及4℃和-20℃2种温度中无显著差异。Ri孢子保藏5个月后,其在纯水中保藏活性高于甘油,在4℃下保藏活性高于-20℃。3)PPM的添加在2个月内能够提高Ri孢子在纯水和甘油中的活性;在2~5个月能够提高Ri孢子在甘油中保藏的活性,而降低在纯水中保藏的活性。因此,短期保藏Ri孢子时,建议选择纯水+PPM于4℃保藏;中期保藏Ri孢子时,建议选择纯水于4℃保藏。研究结果为AM真菌纯孢子短期中期保藏提供一定借鉴。

To investigate the optimal conditions for short-term and medium-term preservation of AM fungal pure spores,this study preserved pure spores of Rhizophagus irregularis(Ri)in four different media:30%glycerol;30%glycerol+plant preservation mixture(PPM);pure water;and pure water+PPM with the temperature of 4℃and-20℃.After 2 and 5 months of storage,the preserved spores were inoculated on host plant root systems to determine the effect of different preservation conditions on the ability of Ri spores to infect the host root systems.The results showed that 1)a large number of dormant spores in pure water medium broke dormancy at 4℃and this preservation condition significantly increased the activity of Ri spores after 5 months of storage,which was 5.08%to 11.07%higher than the initial one.Under other conditions,the activity of Ri spores decreased with the increase of storage time.2)After 2 months of storage,there was no significant difference in Ri spore activity between two preservation media(glycerol and pure water)and two preservation temperature(4℃and-20℃).While after 5 months,the activity of Ri spores in pure water was higher than in glycerol;the activity of Ri spores stored at 4℃was higher than that stored at-20℃.3)PPM addition to pure water and glycerol could improve the activity of Ri spores within 2 months;PPM addition to glycerol could improve the activity of Ri spores within 2-5 months,while reduced the activity of Ri spores in pure water.Therefore,for short-term preservation of Ri spores,pure water+PPM at 4℃is a better choice;for medium-term conservation of Ri spores,it is recommended to choose pure water at 4℃.This study provides some references for the short-and medium-term preservation of AM fungi pure spores.