丛枝菌根(AM)真菌对大青杨苗木根系的影响

应用丛枝菌根(AM)真菌对大青杨苗木进行人工接种,摩西球囊霉(Glomus mosseae)、根内球囊霉(G.intraradices)、弯丝球囊霉(G.sinuosa)、地表球囊霉(G.versiforme)都与盆栽大青杨苗木形成菌根复合体。菌根化苗木的主根长、地径、侧根数、根生物量均与对照苗木差异显著。苗木生物量的累积与菌根侵染率呈显著正相关(P<0.05),证明大青杨为菌根依赖性树种。G.mosseae和G.intraradices侵染率分别是64.4%和67.4%,侵染效果最好。菌根真菌使苗木根系体积增大、总吸收面积增加,特别是使苗木根系的活跃吸收面积显著增加,其中接种G.mosseae的苗木根系活跃吸收面积比是对照处理的1.64倍。根系中活跃吸收面积比与磷、钾元素含量呈显著正相关。苗木生长的盛期和末期,菌根化苗木根系过氧化物酶活性显著高于对照,而在生长后期却显著低于对照(P<0.05)。由于受菌根真菌的影响,苗木根系多酚氧化酶活性显著高于对照(P<0.05),在苗木生长盛期酶活性最强,不同菌种接种的苗木间差异不显著。

The Effects of Arbuscular Mycorrhizal Fungi on the Radicular System of Populus ussuriensis Seedlings

The Populus ussuriensis seedlings were inoculated with four species of AM fungi,and we found that the mycorrhizal compounds could be formed by all the Glomus mosseae,G.intraradices,G.sinuosa and G.versiforme.The taproot length and the ground diameter of inoculated seedlings were significantly different to the controls,so were the numbers of branch roots and the root biomass.The biomass accumulation of seedlings was correlated significantly and positively to the infection rate(P<0.05),which suggests that the P.ussuriensis is characterized by its dependence on the mycorrhization.The infection rate of G.mosseae and G.intraradices were 64.4% and 67.4% respectively.The volume and the total absorption area of root system were increased by inoculation with the AM fungi,especially for the active absorption region of that.The radicular active absorption region of seedlings inoculated with G.mosseae was 1.64 times of the controls.It is tested that the activity of the peroxidase in root system of inoculated poplars at the vigorous and final stage was much increased,while it was little decreased at the later stage as compared with the control treatments.The activity of the radicular polyphenol oxidase was much higher than the not colonized seedlings as effected by the AM fungi.This enzyme activity was highest when the poplar was growing vigorously,and the differences among the different inoculated ones were not significant.