【摘要】 在我国发现了两种柑桔菌根真菌,暂编号为中柑1号和中柑2号。通过显微解剖观察和盆栽接种试验证明二者均属于藻菌类内囊霉属的“泡囊-丛状(V-A)型内生菌根真菌。中柑1号在锦橙根的皮层组织内产生丰富的泡囊和丛状体,菌丝伸出根外形成瘤状吸盘结构。 取七个柑桔品种的实生苗,在盆栽灭菌土的条件下,分别人工接种这种菌根真菌,均使柑桔的根系感染而形成菌根。但不同柑桔品种的菌根感染程度不同,以锦橙对中柑1号和粗柠檬对中柑2号的感染率为最高,枳对两种菌根真菌的感染程度极低,甚至不感染。 菌根显著地促进柑桔植株的生长,但同一种菌根菌对不同的柑桔品种的生长反应不一致。中柑1号使锦橙实生苗的枝茎和根的长度为对照的2倍以上;中柑2号使粗柠檬的长度为对照的2.8倍。以菌根的依赖和根穗比值也说明了菌根对柑桔生长的反应。更多还原

【Abstract】 Two citrus mycorrhizal fungi, found in China, were named C C-l and C C-2 for the present. According to microscopical anatomy observation and pot inoculation experiments, both of them belong to Phytomycetus endophytic fungi and are of highly distinctive vesicular-arbuscular type mycorrhizal in associa-tion with citrus. C C-l possesses the characteristics of producing plenty of ve-sicles more than C C-2 and forming arbuscles in the parenchyma cells of root cortex. Hyphae of C C-l extend into rhizosphere soil to enlarge the absorptive area of roots and hyphae tip forms knotty microverru.In sterilized soil of pot culture, seedlings of seven citrus cultivars were inoculated with these two fungi respectively. Although most seedlings had been infected, yet the degree of mycorrhizal infection varied in different citrus cultivars. The best combinations were ’Glorious’ orange (Citrus senensis) with C C-l and rough lemon (Citrus jambihiri) with C C-2. The percentage of their infection was about 70% and the lowest percentage was the trifoliate orange with these two fungi. Through the experimental period, mycorrhizae were consistently absent from control seedlings.Infection of these mycorrhizal fungi boosted the growth of citrus seedlings. Top growth of orange was increased as much as 2-fold than that of control seedlings. And the stem length of rough lemon infected with C C-2 was increased as much as 2.8-fold than that of control. There is a wide range of dependency on C C-l for growth of the seven citrus cultivars.Mycorrhizal dependency and root-scion ratio were discussed.更多还原