梯棱羊肚菌外源营养作用的影响因素

外源营养袋的应用是国内羊肚菌大田栽培成功的关键技术之一,但其作用机理和影响因素一直没有得到充分的解析。本研究首先于室内建立一个外源营养模型,确认模型中外源营养模块可以向外输出营养,且被梯棱羊肚菌菌丝利用。通过模型实验发现,外源营养添加到贫瘠培养基时,菌体生物量的增加显著高于营养丰富的培养基;在梯棱羊肚菌生长的不同阶段添加外源营养,菌核形成位置不同,并影响生物量的增加,在菌核起始阶段添加,主培养基的生物量增加最多;外源营养的添加位置、块数等因素在本模型中没有检测到对生物量的影响。外源营养使用聚丙烯袋包裹和不包裹比较发现,包裹组的主培养基内生物量增速和总量低于无包裹组,而外源营养块内趋势相反,但最终两组之间外源营养块与主培养基内生物量总和没有显著差异。使用滤纸和铝箔包裹外源营养时,对生物量的影响和聚丙烯袋材质没有显著差别。外源营养碳氮比20:1时,最有利于主培养基生物量的积累。本研究建立的外源营养研究模型得到的结论与大田栽培有较好的一致性,通过模型发现了实际栽培中不容易观察到的现象,有助于对外源营养袋作用机理进行深入研究。

Influencing factors of exogenous nutrient in Morchella importuna

The exogenous nutrient bags (ENB) play an important role in the morel cultivation in China, but the mechanism has not been fully analyzed. In this study, an exogenous nutrition model was first established. The exogenous nutrition module (ENM) in the model could export nutrients and be used by the hyphae of Morchella importuna in the plates, and thereby the effectiveness of the model was confirmed. Adding exogenous nutrition (EN) to infertile medium increase the biomass significantly in comparison with using rich nutrition medium. The sclerotia formed at different locations in the plates when EN was added at different growth stages of M. importuna and the biomass increment was affected. When EN was added at the initial stage of sclerotial formation, the biomass of M. importuna maximally increased. Factors such as the adding location and amount of EN did not affect the biomass observed in this model. ENMs wrapped with and without polypropylene bags did not significantly affected the total biomass, however, the growth rate and total biomass in the wrapped group were lower than those of non-wrapped group in plate, while the opposite trend occurred in ENM. Wrapping EN in filter paper and aluminum foil appeared to be similar in affecting the fungal biomass as compared with wrapping EN in polypropylene bag. C/N ratio of 20:1 was most advantageous for accumulation of biomass. Exogenous nutrition research model established in this study was consistent with the field cultivation of M. importuna, and the phenomenon that was not easy to be observed in cultivation became visible in the model, being helpful for further study of the mechanism of exogenous nutrition.