Characteristics and influencing factors of ectomycorrhizae infection in Quercus sect.Heterobalanus of Hengduan mountains
[Objective]To clarify the infection characteristics of the Ectomycorrhizae(ECM)of the Quercus sect.Heterobalanus(QSH)and its interrelationship with various habitat factors.[Method]The roots and soil of QSH in Sichuan and Tibet were used as research materials to observe the morphological characteristics of ECM in QSH,determine the ECM infection rate and analyze the relationship between ECM infection rate and arbuscular mycorrhizal fungi(AMF)spore density,elevation,soil pH,soil organic carbon(SOC),available potassium(AK),total nitrogen(TN),total phosphorus(TP)and N∶P.[Result]The ECM morphology of QSH in the study area relatively single,mainly consisting of single-axis pinnate branches and single-axis branches.The anatomical structure observed that the ECM formed Hartig net between the root cortical cells of the QSH,and the infestation rate of ECM was high,in the range of 51.37%-58.68%,and the infection intensity were all of level 4,but there were no significant difference in the level of species and life forms(P＞0.05).The average density of AMF spores was 123.92 per gram,the mean soil pH was 5.32,and the average contents of soil SOC,AK,TN,TP,and N∶P were 5.32,43.22 g/kg,53.9 g/kg,1.03 g/kg,113.33 mg/kg,and 5.58,respectively.Factor analysis showed that all 8 habitat factors had an impact on ECM infection rate,and the ECM infection rate was significantly positively correlated with soil available K and TN content(P＜0.05),while no significant correlation was shown with other factors(P＞0.05).[Conclusion]The ECM in the QSH plant prefers a weakly acidic environment,and the expansion of AMF spores in the soil does not exclude ECM infection.N and K elements were the dominant factors affecting ECM infection.In addition,the comprehensive changes of various habitat factors in the small ecosystem of QSH forests at different altitudes can also affect ECM infection.Furthermore,the ECM can change soil pH through feedback when its infection tends to a saturated state,but the regulation of soil C is not significant.
NETL
NSTL
万方数据
