丛枝菌根真菌对香蕉试管苗植株生长和矿质营养吸收的影响

以Williams香蕉(MusaAAA)试管苗为材料,在温室盆栽条件下研究丛枝菌根真菌(AM真菌)对香蕉植株矿质营养和营养生长的影响。试验设3个处理,不接种对照和2个菌根接种处理:接种单一菌种Glomusversiform、接种混合菌种G.versiform、G.epigaeam、G.cadedonium。结果表明,香蕉植株的菌根侵染率为22.8%～32.9%;接种AM真菌促进了香蕉植株的营养生长,显著地增加地上部和根系的干重,其菌根依赖性达到30.8%～37.8%,植株的株高、叶片数和叶片长度略有提高;接种单一菌种增加了须根的数量,但2个接种处理均降低须根的长度,使得总根长减少;单一接种剂和混合接种剂分别显著提高植株的P和K含量,2个接种处理都显著地促进了植株对N、P、K的吸收,P增幅最大,为70%～120%,K的增幅次之,为80%左右,N的增幅最小,为40%～60%。结果还表明,混合接种剂的生长促进效果略好于单一接种剂。

Influence of Arbuscular Mycorrhizal Fungi on Mineral Nutrients Uptake and Growth of Micro-propagated Banana Plantlets

Experiment was conducted with Williams banana cultivar grown under potted conditions. Influence of arbuscular mycorrhizal (AM) fungi on mineral nutrition uptake and vegetative growth of micro-propagated banana plantlets were studied. Three treatments were established, including non-mycorrhizal control, inoculation with single fungal specie Glomus versiform and inoculation with mixed fungal species G. versiform, G. epigaeam and G. cadedonium. Results showed that mycorrhizal colonization of banana plantlets were 22.8%～32.9%. AM fungal inoculation promoted the vegetative growth of plantlets, significantly increased shoot and root dry matter, with mycorrhizal dependency reaching 30.8%～37.8%. Plant height, leaf number and leaf length were also slightly increased due to fungal inoculation. Although fibrous root number was increased after inoculation with single fungal species, fibrous root length was decreased in both mycorrhizal treatments, leading to a decreased total root length. Inoculation with single fungal species and mixed fungal species significantly elevated plantlet P and K contents, respectively. Uptake of N, P and K were enhanced in both mycorrhizal treatments, with the highest increasing magnitude of 70%～120% for P, about 80% for K, and the lowest one of 40%～60% for N. Results also indicated that growth promotion of mixed fungal species inoculum was slightly better than that of single fungal specie inoculum.